Chlorpyrifos; Tolerance Revocation, 99184-99207 [2024-28332]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 89, Number 237 (Tuesday, December 10, 2024)]
[Proposed Rules]
[Pages 99184-99207]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-28332]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2024-0431; FRL-12415-01-OCSPP]


Chlorpyrifos; Tolerance Revocation

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing to revoke all tolerances for residues of 
chlorpyrifos, except for those associated with the use of chlorpyrifos 
on the following crops: alfalfa, apple, asparagus, tart cherry, citrus, 
cotton, peach, soybean, strawberry, sugar beet, and spring and winter 
wheat. This proposal also addresses the request to revoke all 
chlorpyrifos tolerances contained in the September 12, 2007, petition 
submitted by the Natural Resources Defense Council (NRDC) and Pesticide 
Action Network North America (PANNA).

DATES: Comments must be received on or before February 10, 2025.

ADDRESSES: Submit your comments, identified by docket identification 
(ID) number EPA-HQ-OPP-2024-0431, through the Federal eRulemaking 
Portal at https://www.regulations.gov. Follow the online instructions 
for submitting comments. Do not submit electronically any information 
you consider to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Additional 
instructions on commenting and visiting the docket, along with more 
information about dockets generally, is available at https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Patricia Biggio, Pesticide Re-
Evaluation Division (7508M), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Washington, 
DC 20460-0001; telephone number: 202-566-0700; email address: 
[email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

    This action is directed to the public in general and may be of 
interest to a wide range of stakeholders including environmental, human 
health, and agricultural advocates; the chemical industry; pesticide 
users; and members of the public interested in the sale, distribution, 
or use of pesticides. Since others also may be interested, the Agency 
has not attempted to describe all the specific entities that may be 
affected by this action.

B. How can I get electronic access to other related information?

    You may access a frequently updated electronic version of 40 CFR 
part 180 through the Office of the Federal Register's e-CFR site at 
https://www.ecfr.gov/current/title-40.

C. What action is the Agency proposing?

    EPA is proposing to revoke all tolerances for residues of the 
insecticide chlorpyrifos as contained in 40 CFR 180.342, except for 
those tolerances associated with 11 uses that were proposed for 
retention in the Agency's December 2020 Chlorpyrifos Proposed Interim 
Decision (2020 PID). (Ref. 1) As a result of voluntary cancellations 
and label amendments, registrations of chlorpyrifos will be limited in 
terms of food uses to these crops within certain states, as proposed in 
the 2020 PID and EPA's Updated Chlorpyrifos Refined Drinking Water 
Assessment for Registration Review (September 2020) (``2020 DWA'') as 
described in Unit III below. (Ref. 2)
    Therefore, the Agency is proposing to revoke all other tolerances 
that are not needed as a result of the cancellations, including uses in 
food handling establishments and food service establishments. This 
proposal will also address the request to revoke chlorpyrifos 
tolerances in the pending 2007 Petition from NRDC and PANNA.

D. What is EPA's authority for taking this action?

    Pursuant to its authority under section 408 of the Federal Food, 
Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a (https://www.govinfo.gov/link/uscode/21/346a), EPA may respond to a petition 
filed with the Agency under FFDCA section 408(d) by issuing a proposed 
and final rule under FFDCA section 408(e). The 2007 Petition requested 
that EPA revoke chlorpyrifos tolerances, as well as cancel chlorpyrifos 
registrations. EPA is proposing to revoke chlorpyrifos tolerances that 
will no longer be necessary due to the cancellation of domestic uses on 
those commodities. Under section 408(e) of the FFDCA, EPA may issue a 
rule revoking tolerances after providing notice of a proposed 
rulemaking and a period of not less than 60 days for public comment. 21 
U.S.C. 346a(e).

E. What is the expected impact of this action?

    The revocations of these tolerances are not expected to present 
extraordinary circumstances because the registrants have requested, 
pursuant to the Federal Insecticide, Fungicide, and Rodenticide Act 
(FIFRA) section 6(f) (7 U.S.C. 136d(f)), to voluntarily cancel uses 
associated with these tolerances. EPA is in the process of approving 
those cancellation requests under FIFRA, which means that soon the 
tolerances will no longer be needed to cover residues of chlorpyrifos 
in or on those food commodities.
    The revocations of tolerances could impact foreign producers who 
use chlorpyrifos to control insect pests and importers of those 
commodities. Shipments found to have residues could not be sold in the 
United States, which may represent a loss to importers or their trading 
partners. It is possible that these effects could have downstream 
effects, such as raising costs to U.S. consumers of these commodities. 
Regardless of the potential impacts of this action, tolerances can only 
be maintained if they are safe, which is a risk-only analysis under the 
FFDCA.

F. What can I do if I want the Agency to maintain, for import purposes, 
a tolerance that the Agency proposes to revoke?

    This proposed rule provides a 60-day public comment period. All 
chlorpyrifos registrants have already voluntarily requested 
cancellation of all the uses of chlorpyrifos associated with the 
tolerances proposed for revocation in this notice. Once those 
cancellations are effective, those uses of chlorpyrifos on these 
commodities will no longer be registered in the United States, and once 
use terminates under the applicable existing stocks provisions, the 
tolerances will no longer be necessary to cover residues from use of 
the pesticide. Any food being moved through interstate commerce after 
tolerances are revoked would be covered by the FFDCA channels of trade 
provision, 21 U.S.C. 346a(l)(5), as described in Unit VII.A. The 
Agency's typical process, e.g., during registration review, is to 
remove tolerances from the regulations that are no longer necessary. 
This avoids confusion among the regulated community by reflecting 
registered uses and label directions and helps with consistency in 
enforcement under the FFDCA and FIFRA.
    The only reason to retain a tolerance in such circumstances is for 
import purposes. Any commenter seeking to retain tolerances for import 
purposes

[[Page 99185]]

must provide a comment to that effect and include information 
demonstrating the need for retaining a specific tolerance for specific 
imports, even if they have previously provided this information; a 
hypothetical need based on the potential for some commodities 
containing chlorpyrifos residues to one day be imported into the United 
States is insufficient.
    If any data are necessary to retain the tolerances for import 
purposes, EPA will issue an order in the Federal Register under FFDCA 
section 408(f). The order would specify data needed and the timeframes 
for submission of the data and would require that within 90 days some 
person or persons notify EPA that they will submit the data. If the 
data are not submitted as required in the order, EPA will take 
appropriate action under FFDCA.
    After considering comments that are received in response to this 
proposed rule, EPA will issue a final rule.

G. What should I consider as I prepare my comments for EPA?

    1. Submitting CBI. Do not submit CBI information to EPA through 
https://www.regulations.gov or email. If you wish to include CBI in 
your comment, please follow the applicable instructions at https://www.epa.gov/dockets/commenting-epa-dockets#rules and clearly mark the 
part or all of the information that you claim to be CBI. In addition to 
one complete version of the comment that includes information claimed 
as CBI, a copy of the comment that does not contain the information 
claimed as CBI must be submitted for inclusion in the public docket. 
Information so marked will not be disclosed except in accordance with 
procedures set forth in 40 CFR part 2.
    2. Tips for preparing your comments. When preparing and submitting 
your comments, see the commenting tips at https://www.regulations.gov/faq.
    3. Environmental justice. EPA seeks to achieve environmental 
justice--the just treatment and meaningful involvement of all people, 
regardless of income, race, color, national origin, Tribal affiliation, 
or disability, in Agency decision-making and other Federal activities 
that affect human health and the environment so that people are fully 
protected from disproportionate and adverse human health and 
environmental effects (including risks). To help address potential 
environmental justice issues, the Agency seeks information on any 
groups or segments of the population who, as a result of their 
location, cultural practices, or other factors, may have atypical or 
disproportionate and adverse human health impacts or environmental 
effects from exposure to chlorpyrifos, compared to the general 
population.

H. What is contained in this proposed rule?

    The following provides a brief roadmap of the Units in this 
proposed rule.
     Unit II contains an overview of the relevant statutory 
background under the FFDCA and FIFRA as well as the regulatory status 
of chlorpyrifos. This Unit also provides a summary of the various 
recent legal challenges to the chlorpyrifos tolerances.
     Unit III describes the Agency's proposal to revoke 
tolerances that will not be needed as a result of the approval of 
registrants' requests to cancel chlorpyrifos uses on certain food 
commodities.
     Unit IV contains a safety determination that supports the 
tolerances that are not proposed for revocation.
     Unit V contains the Agency's responses to specific claims 
raised in the 2007 Petition not otherwise addressed in the rest of the 
proposed rule.
     Units VI, VII, and VIII contain EPA's request for public 
comment, discuss EPA's intention for phasing out the tolerances, and 
consistency with other statutory requirements and executive orders.

II. Background

A. What is a tolerance?

    A ``tolerance'' represents the maximum level for residues of 
pesticide chemicals legally allowed in or on food, which includes raw 
agricultural commodities, processed foods, and feed for animals. Under 
the FFDCA, residues of a pesticide chemical that are not covered by a 
tolerance or exemption from the requirement of a tolerance are 
considered unsafe. See 21 U.S.C. 346a(a)(1). Foods containing unsafe 
residues are deemed adulterated and may not be distributed in 
interstate commerce. See 21 U.S.C. 331(a), 342(a)(2)(B). This applies 
to both food treated domestically with a pesticide registered in the 
United States or treated in another country and imported into the 
United States. Thus, before registering any food-use pesticide (i.e., a 
pesticide use that is likely to result in residues in or on food) under 
FIFRA, 7 U.S.C. 136 et seq., EPA ensures that any necessary tolerances 
or exemptions are in place. 40 CFR 152.112(g). EPA also establishes 
tolerances or exemptions for pesticides not registered in the United 
States in order for commodities treated with those pesticides to be 
imported.

B. FFDCA/FIFRA Background

1. FFDCA
    FFDCA section 408(b) authorizes EPA to establish a tolerance, if 
the Agency determines that a tolerance is safe. See 21 U.S.C. 346a(b). 
If EPA determines that a tolerance is not safe, EPA must modify or 
revoke that tolerance. The FFDCA defines ``safe'' to mean that ``there 
is a reasonable certainty that no harm will result from aggregate 
exposure to the pesticide chemical residue, including all anticipated 
dietary exposures and all other exposures for which there is reliable 
information.'' 21 U.S.C. 346a(b)(2)(A)(ii). This includes exposure 
through drinking water and in residential settings but does not include 
occupational exposure.
    FFDCA section 408(b)(2)(C) requires EPA to give special 
consideration to the exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical 
residue[s].'' 21 U.S.C. 346a(b)(2)(C). This provision also creates a 
presumption that EPA will use an additional safety factor for the 
protection of infants and children. Specifically, it directs that ``in 
the case of threshold effects, . . . an additional tenfold margin of 
safety for the pesticide chemical residue and other sources of exposure 
shall be applied for infants and children to take into account 
potential pre- and post-natal toxicity and completeness of the data 
with respect to exposure and toxicity to infants and children.'' (21 
U.S.C. 346a(b)(2)(C)) EPA is permitted to ``use a different margin of 
safety for the pesticide chemical residue only if, on the basis of 
reliable data, such margin will be safe for infants and children.'' 
(Id.) Due to Congress's focus on both prenatal and post-natal toxicity, 
EPA has interpreted this additional safety factor as pertaining to 
risks to infants and children that arise due to prenatal exposure as 
well as to exposure during childhood years. This section providing for 
the special consideration of infants and children in section 
408(b)(2)(C) was added to the FFDCA by the Food Quality Protection Act 
(FQPA) in 1996; therefore, this additional margin of safety is referred 
to throughout this proposed rule as the FQPA safety factor (SF).
    Finally, FFDCA section 408(b)(2)(D) contains several factors that 
EPA considers when making determinations about establishing, modifying, 
or

[[Page 99186]]

revoking tolerances. 21 U.S.C. 346a(b)(2)(D).
    Any person may file a petition requesting that EPA establish, 
modify, or revoke a tolerance. 21 U.S.C. 346a(d)(1). After publishing 
notice of receipt of that petition and after giving due consideration, 
EPA may issue a final or proposed rule establishing, modifying, or 
revoking the tolerances or issue an order denying the petition. 21 
U.S.C. 346a(d)(4)(A).
2. FIFRA
    Under FIFRA (7 U.S.C. 136 et seq.), EPA regulates the sale, 
distribution, and use of pesticides. While FFDCA authorizes the 
establishment of legal limits for pesticide residues in food, FIFRA 
generally requires the approval of pesticides prior to their sale and 
distribution (id. at section 136a(a)) and establishes a registration 
regime for regulating the use of pesticides. In order for a pesticide 
to be registered, EPA must determine that a pesticide ``will not 
generally cause unreasonable adverse effects on the environment,'' 
among other things. (Id. at section 136a(c)(5)) The term ``unreasonable 
adverse effects on the environment'' is defined to include ``a human 
dietary risk from residues that results from a use of a pesticide in or 
on any food inconsistent with the standard under section 346a of Title 
21.'' (Id. at section 136(bb)) The FFDCA safety standard was integrated 
into the FIFRA registration standard through the FQPA, which also 
directed that EPA coordinate, to the extent practicable, revocations of 
tolerances with pesticide cancellations under FIFRA. (21 U.S.C. 
346a(l)(1)).
    Also under FIFRA, EPA is required to re-evaluate existing 
registered pesticides every 15 years in a process called ``registration 
review.'' (7 U.S.C. 136(a)(g)) The purpose of registration review is 
``to ensure that each pesticide registration continues to satisfy the 
FIFRA standard for registration,'' (40 CFR 155.40(a)(1)) taking into 
account changes that have occurred since the last registration 
decision, including any new relevant scientific information and any 
changes in the law or regulations, policy, risk-assessment procedures 
or methods, and data requirements. (40 CFR 155.53(a)) To ensure that a 
pesticide continues to meet the standard for registration, EPA must 
determine, based on the available data, including any additional 
information that has become available since the pesticide was 
originally registered or previously re-evaluated, that the pesticide 
does not cause ``unreasonable adverse effects on the environment.'' (7 
U.S.C. 136a(c)(1), (5); see also 40 CFR 152.50) As part of the 
registration review of a pesticide, EPA also evaluates whether existing 
tolerances are safe and whether any changes to existing tolerances are 
necessary or appropriate. Pesticide products that do not meet the FIFRA 
standard for registration may be cancelled pursuant to the procedures 
in FIFRA section 6, 7 U.S.C. 136d. That provision of FIFRA also 
provides a mechanism for registrants to request voluntary cancellation 
of registered products or to request termination of specific uses on 
any registered product, at any time for any reason. 7 U.S.C. 136d(f). 
If a registrant requests such cancellation or use termination, EPA 
publishes notice of that request and allows for a public comment 
period. 7 U.S.C. 136d(f)(1)(B) and (C). After the public comment 
period, EPA may approve or deny the request. 7 U.S.C. 136d(f)(1)(D).

C. Chlorpyrifos Background

    Chlorpyrifos (0,0-diethyl-0-3,5,6-trichloro-2-pyridyl 
phosphorothioate) is a broad-spectrum, chlorinated organophosphate (OP) 
insecticide. Chlorpyrifos also forms the more toxic and potent 
acetylcholinesterase (AChE) inhibitor, chlorpyrifos oxon.
    Chlorpyrifos has been registered for use in the United States since 
1965. These uses have included a wide range of food crops (e.g., 
soybean, wheat) and non-food use sites (e.g., tobacco, ornamental 
flowering plants, turf), as well as public health uses (e.g., aerial 
and ground-based fogger mosquito adulticide treatments) and residential 
uses (e.g., roach bait products, and individual fire ant mound 
treatments). In 2000, chlorpyrifos registrants reached an agreement 
with EPA to voluntarily cancel all residential use products except 
those registered for ant and roach baits in child-resistant packaging 
and fire ant mound treatments. Most recently, as discussed later in 
this document, chlorpyrifos registrants have voluntarily requested to 
cancel all food uses except the 11 uses described in Unit III. Pursuant 
to those requests, EPA has already cancelled most of those registered 
food uses and expects to process the remaining cancellation requests by 
the end of this calendar year (2024). (Ref. 3-8).
    EPA is currently working to complete the registration review of 
chlorpyrifos. As part of that process, EPA has completed multiple human 
health risk assessments (HHRAs) since 2011. As additional data became 
available for chlorpyrifos and its metabolite of concern, chlorpyrifos 
oxon, EPA completed revised draft human health risk assessments in 
2014, 2016, and 2020. A refined drinking water assessment (DWA) was 
completed in 2016 (2016 DWA), and the Updated DWA was completed in 2020 
(2020 DWA). In December 2020, EPA issued the Chlorpyrifos Proposed 
Interim Decision (2020 PID). (Ref. 1) At this time, EPA is working on 
responding to comments received on the 2020 PID and supporting risk 
assessments and on preparing an updated human health risk assessment 
and amended proposed interim registration review decision. EPA 
anticipates issuing an amended PID in 2026 followed by the Chlorpyrifos 
Interim Decision.
    It should be noted that there has been an international effort to 
develop a battery of new approach methodologies (NAMs) to inform the 
developmental neurotoxicity (DNT) potential for individual chemicals. 
The assays in this battery are expected to provide a mechanistic 
understanding of the underlying biological processes that may be 
vulnerable to chemically-induced disruption. Since the integration of 
data from the DNT NAM battery for the chlorpyrifos risk assessment is 
in progress, it has not been incorporated into the risk assessment that 
supports this rulemaking. It is intended to be incorporated into the 
amended human health risk assessment anticipated for release in 2025 in 
support of registration review, and the Agency will provide any updates 
on the status of this effort through the ongoing registration review of 
chlorpyrifos.

D. 2007 Petition and Associated Litigation

    In September 2007, PANNA and the NRDC jointly submitted to EPA a 
petition under FFDCA section 408(d), seeking revocation of all 
chlorpyrifos tolerances. The 2007 Petition also sought the cancellation 
of all chlorpyrifos pesticide product registrations under FIFRA section 
6, 7 U.S.C. 136d. The 2007 Petition raised several claims, which are 
discussed in Unit V., regarding both EPA's 2006 FIFRA reregistration 
eligibility decision (RED) and active registrations of chlorpyrifos in 
support of the request for tolerance revocations and product 
cancellations.
    In March 2009, EPA decided it would be appropriate to address these 
issues and the 2007 Petition claims in connection with the registration 
review of chlorpyrifos under FIFRA section 3(g) and decided to expedite 
that review, intending to finalize it several years in advance of the 
registration review deadline at that time, October 1, 2022.

[[Page 99187]]

    On July 16, 2012, EPA denied the one FIFRA claim in a letter to the 
Petitioners and offered a partial response on several of the FFDCA 
claims; however, because the complexity of these scientific issues 
precluded EPA from finishing its review according to EPA's original 
timeline, the Petitioners brought legal action in the U.S. Court of 
Appeals for the Ninth Circuit to compel EPA to either issue an order 
denying the 2007 Petition or to grant the 2007 Petition by initiating 
the tolerance revocation process. On August 10, 2015, the Ninth Circuit 
ordered EPA to ``issue either a proposed or final revocation rule or a 
full and final response to the administrative [P]etition by October 31, 
2015.'' In re Pesticide Action Network N. Am., 798 F.3d 809, 815 (9th 
Cir. 2015).
    In response to that 2015 order, EPA issued a proposed rule to 
revoke all tolerances for chlorpyrifos on October 28, 2015 (published 
in the Federal Register on November 6, 2015 (80 FR 69080)). Although 
EPA noted that further evaluation might enable more tailored risk 
mitigation, EPA was unable to conclude, based on the information before 
EPA at the time, that the tolerances were safe, since the aggregate 
exposure to chlorpyrifos, driven by drinking water exposures, exceeded 
safe levels. In November 2016, EPA issued a notice of data availability 
announcing the availability of a revised human health risk assessment. 
(81 FR 81049) (Nov. 17, 2016) (Ref. 9)
    In the meantime, the Ninth Circuit ordered EPA to take final action 
on its proposed revocation rule and issue its final response to the 
Petition by December 30, 2016. In re Pesticide Action Network N. Am., 
808 F.3d 402 (9th Cir. 2015). EPA requested an extension of the 
deadline in order to be able to fully consider the July 2016 FIFRA 
Scientific Advisory Panel (SAP) report regarding chlorpyrifos 
toxicology, but the Ninth Circuit ordered EPA to complete its final 
action by March 31, 2017. In re Pesticide Action Network of North 
America v. EPA, 840 F.3d 1014 (9th Cir. 2016).
    Accordingly, EPA issued a formal denial of the FFDCA claims in the 
2007 Petition in an order issued in March 2017. (Ref. 10) In that 2017 
Petition Denial, EPA concluded that it was not required to complete--
and would not complete--any tolerance revocation of chlorpyrifos 
without resolution of those issues during the ongoing FIFRA 
registration review of chlorpyrifos. Chlorpyrifos; Order Denying PANNA 
and NRDC's Petition to Revoke Tolerances, 82 FR 16581 (April 5, 2017) 
(``2017 Petition Denial''). EPA also denied objections filed in 
response to the 2017 Petition Denial on July 24, 2019. See 
Chlorpyrifos; Final Order Denying Objections to March 2017 Petition 
Denial Order, 84 FR 35555 (July 24, 2019) (``2019 Objections Denial''). 
In the 2019 Objections Denial, EPA concluded that it was appropriate to 
deny the objections related to new issues raised after EPA's 2006 
tolerance reassessment and reregistration of chlorpyrifos as these 
issues are being addressed according to the schedule for EPA's ongoing 
registration review of chlorpyrifos.
    The 2019 Objections Denial was challenged by several farmworker 
advocacy groups and States, and in April 2021, the Ninth Circuit issued 
its decision, finding that EPA's denial was arbitrary and capricious 
based on the record before the court. See League of United Latin Am. 
Citizens, et al., v. Regan, 996 F.3d 673 (9th Cir. 2021). The Ninth 
Circuit vacated EPA's petition response and ordered EPA to grant the 
2007 Petition; to issue a final rule either revoking all chlorpyrifos 
tolerances or modifying the chlorpyrifos tolerances, provided EPA could 
make a determination that those modified tolerances met the safety 
standard mandated by the FFDCA; and to cancel registered chlorpyrifos 
products or uses associated with the revoked tolerances. The Ninth 
Circuit ordered EPA to issue that final rule within 60 days of the 
issuance of the mandate and to cancel the registered pesticides in a 
timely manner. Frustrated with the ``[then-] thirteen years of 
interminable delay,'' the Ninth Circuit concluded that ``further 
factfinding'' would not be reasonable and that ``immediate issuance of 
a final regulation is the only reasonable action,'' citing the FFDCA 
provision authorizing issuance of a final rule `` `without further 
notice and without further period for public comment.' '' See id. at 
702, citing 21 U.S.C. 136a(d)(4)(A)(i) (emphasis in original).
    On August 30, 2021, EPA complied with the Ninth Circuit's ruling by 
granting the 2007 Petition and issuing the Final Tolerance Rule for 
Chlorpyrifos, which revoked all tolerances for chlorpyrifos. See 86 FR 
48315 (Aug. 30, 2021) (``2021 Final Rule''). EPA explained in the 2021 
Final Rule that it was unable to determine that there was a reasonable 
certainty of no harm for aggregate exposure, including food, drinking 
water, and residential exposure, based on the available data and the 
anticipated exposures from all of the then-currently registered uses of 
chlorpyrifos. EPA's analysis indicated that risk from aggregate 
exposures from all of the then-registered uses would exceed the 
Agency's levels of concern. To satisfy international trade 
considerations, the 2021 Final Rule allowed the tolerances to remain in 
effect for six months until February 28, 2022, at which time the 
tolerances expired. Pursuant to FFDCA section 408(g), registrants and 
grower groups, among others, filed objections to the 2021 Final Rule, 
which EPA denied on February 28, 2022. See Chlorpyrifos; Final Order 
Denying Objections, Requests for Hearings, and Requests for a Stay of 
the August 2021 Tolerance Final Rule. 87 FR 11222 (Feb. 28, 2022) 
(``2022 Objections Denial'').
    The 2021 Final Rule and 2022 Objections Denial were challenged by a 
chlorpyrifos registrant, Gharda Chemicals International, Inc. (Gharda), 
and 19 grower groups in the U.S. Court of Appeals for the Eighth 
Circuit. The grower groups included Red River Valley Sugarbeet Growers 
Association, U.S. Beet Sugar Association, American Sugarbeet Growers 
Associations, Southern Minnesota Better Sugar Cooperative, American 
Crystal Sugar Company, Minn-Dak Farmer Cooperative, American Farm 
Bureau Federation, American Soybean Association, Iowa Soybean 
Association, Minnesota Soybean Growers Association, Missouri Soybean 
Association, Nebraska Soybean Association, South Dakota Soybean 
Association, North Dakota Soybean Growers Association, National 
Association of Wheat Growers, Cherry Marketing Institute, Florida Fruit 
and Vegetable Association, Georgia Fruit and Vegetable Growers 
Association, and the National Cotton Council of America. These 
petitioners argued, among other things, that EPA should have modified 
tolerances by leaving tolerances in place consistent with the 11 uses 
proposed the 2020 PID, rather than revoking all tolerances.
    On November 2, 2023, the Eighth Circuit issued its decision, 
vacating the 2021 Final Rule (and EPA's response to the 2007 Petition 
once again) and remanding the matter to EPA for further proceedings. 
See Red River Valley Sugarbeet Growers Ass'n, et al. v. Regan, 85 F.4th 
881 (8th Cir. 2023). The Eighth Circuit's decision noted that the 
Agency had ``identified 11 specific candidates'' of food and feed crop 
uses in the 2020 PID as part of Registration Review. Although the 2021 
Final Rule (and the 2022 Objections Denial) explained why EPA was not 
modifying the tolerances consistent with the 2020 PID, the Eighth 
Circuit concluded that the 2021 Final Rule ignored modification of 
tolerances as an option for addressing the Ninth Circuit's

[[Page 99188]]

mandate and thus was arbitrary and capricious. The Eighth Circuit's 
mandate issued on December 28, 2023, at which time all chlorpyrifos 
tolerances were automatically reinstated. EPA amended the Code of 
Federal Regulations on February 5, 2024, to reflect the Eighth 
Circuit's reinstatement of chlorpyrifos tolerances. See Chlorpyrifos; 
Reinstatement of Tolerances, 89 FR 7625 (Feb. 5, 2024).

III. Proposed Rule

    In this document, EPA is proposing to revoke tolerances to reflect 
registrants' requests to voluntarily cancel food uses and submission of 
label amendments consistent with the 2020 PID and supporting documents. 
EPA anticipates approving all submitted cancellation requests by the 
end of 2024. After approval of the cancellation requests and label 
amendments, the only food uses that will remain on federally registered 
chlorpyrifos products are listed below and will be limited to the 
following States:
    1. Alfalfa: Arizona, Colorado, Iowa, Idaho, Illinois, Kansas, 
Michigan, Minnesota, Missouri, Montana, North Dakota, Nebraska, New 
Mexico, Nevada, Oklahoma, Oregon, South Dakota, Texas, Utah, 
Washington, Wisconsin, and Wyoming.
    2. Apple: Alabama, Delaware, Georgia, Idaho, Indiana, Kentucky, 
Maryland, Michigan, New Jersey, New York, Ohio, Oregon, Pennsylvania, 
Tennessee, Virginia, Vermont, Washington, West Virginia, and 
Washington, DC.
    3. Asparagus: Michigan.
    4. Tart cherry: Michigan.
    5. Citrus: Alabama, Florida, Georgia, North Carolina, South 
Carolina, and Texas.
    6. Cotton: Alabama, Florida, Georgia, North Carolina, South 
Carolina, and Virginia.
    7. Peach: Alabama, Delaware, Florida, Georgia, Maryland, Michigan, 
North Carolina, New Jersey, New York, Ohio, Pennsylvania, South 
Carolina, Texas, Virginia, Vermont, West Virginia, and Washington, DC.
    8. Soybean: Alabama, Colorado, Florida, Georgia, Iowa, Illinois, 
Indiana, Kansas, Kentucky, Minnesota, Missouri, Montana, North 
Carolina, North Dakota, Nebraska, New Mexico, Ohio, Oklahoma, 
Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Virginia, 
Wisconsin, West Virginia, and Wyoming.
    9. Strawberry: Oregon
    10. Sugar beet: Iowa, Idaho, Illinois, Michigan, Minnesota, North 
Dakota, Oregon, Washington, Wisconsin.
    11. Wheat:
    a. Spring wheat: Colorado, Kansas, Missouri, Montana, North Dakota, 
Nebraska, South Dakota, and Wyoming.
    b. Winter wheat: Colorado, Iowa, Kansas, Minnesota, Missouri, 
Montana, North Dakota, Nebraska, Oklahoma, South Dakota, Texas, and 
Wyoming.
    EPA notes that not all chlorpyrifos products are registered for 
these uses in all of the above listed States. If the use is not 
registered on a particular chlorpyrifos product, it must be added via 
the FIFRA section 3 registration process in order for that product to 
be used in a particular State. Moreover, EPA notes that since the 
issuance of the 2020 PID, several States have prohibited use of 
chlorpyrifos, including California, Hawaii, New York, Maryland, and 
Oregon. States may regulate the sale or use of federally registered 
pesticides within their State. Although these particular States have 
adopted additional restrictions, the voluntary cancellation requests 
for the federally registered uses only reflected EPA's proposal in the 
2020 PID and did not incorporate any additional restrictions at the 
State level. As a result, EPA's proposed tolerance revocations reflect 
only the adjustments to the federal registrations, but the continued 
registration review of chlorpyrifos allows for further consideration of 
this issue.
    In addition, the submitted label amendments are consistent with the 
reduced application frequency and rates for these uses that were used 
in the 2020 DWA and support the Estimated Drinking Water Concentration 
(EDWC) calculations. (Ref. 2) EPA expects to approve the last of these 
label amendments by the end of 2024. Consistent with the terms of the 
cancellation orders, use of these previously registered chlorpyrifos 
products on any crops beyond the 11 uses listed above and restricted as 
described herein will be prohibited after June 30, 2025.
    To cover residues of chlorpyrifos in food from these remaining food 
uses, the following existing tolerances are not being revoked: alfalfa, 
forage; alfalfa, hay; apple, apple, wet pomace; beet, sugar, dried 
pulp; beet, sugar, molasses; beet, sugar, roots; beet, sugar, tops; 
cattle, fat; cattle, meat; cattle, meat byproducts; cherry, tart; 
citrus, dried pulp; citrus, oil; cotton, undelinted cotton seed; egg; 
fruit, citrus, group 10; goat, fat; goat, meat; goat, meat byproducts; 
hog, fat; hog, meat; hog, meat byproducts; horse, meat; horse, meat 
byproducts; milk, fat (reflecting 0.01 ppm in whole milk); peach; 
poultry, fat; poultry, meat; poultry, meat byproducts; sheep, fat; 
sheep, meat; sheep, meat byproducts; soybean, seed; strawberry; wheat, 
forage; wheat, grain; and wheat, straw in section 40 CFR 180.342(a) and 
asparagus in 180.342(c).
    EPA is proposing to revoke all other tolerances for residues of 
chlorpyrifos on specific food commodities (40 CFR 180.342(a)(1)); on 
all food commodities treated in food handling and food service 
establishments in accordance with prescribed conditions (40 CFR 
180.342(a)(2) and(a)(3)); and on grape when used under regional 
registrations (40 CFR 180.342(c)).
    EPA is proposing these tolerance revocations because all the 
registrants have submitted voluntary cancellation requests for all food 
uses that trigger the need for those tolerances. Moreover, all 
registrants retaining any of the 11 food uses listed above have 
submitted label amendments that limit uses to the specific States 
listed above and restrict application rates and application frequency 
consistent with the assumptions supporting the 2020 DWA. As of the 
publication of this proposed rule, 41 products have been cancelled, and 
12 products have had all food uses but the 11 uses identified above 
cancelled. EPA has approved amended labels for 15 products. EPA is 
currently working to process and expects to complete its issuance of 
cancellation orders by the end of 2024, at which time no food uses 
beyond the 11 identified above will remain registered.
    Because of the cancellation of these uses, these tolerances will no 
longer be needed to cover residues from use of the pesticide within the 
United States. Removing unnecessary tolerances helps to avoid confusion 
among stakeholders about where the pesticide can be used and improves 
coordination under FIFRA and the FFDCA. EPA's typical practice when 
tolerances are no longer needed due to the cancellation of registered 
uses or products is to remove them from the Code of Federal 
Regulations, usually carried out after being discovered as not 
necessary in registration review. See, e.g., Pesticide Tolerance; 
Exemptions, Petitions, Revocations, etc.: Implementing Registration 
Review Decisions for Certain Pesticides; Aluminum tris (O-
ethylphosphonate), Carbon disulfide, et al., (88 FR 46077) (July 19, 
2023). (Ref. 11) There is no requirement, however, to wait until the 
conclusion of registration review, and since EPA is aware of the lack 
of necessity of these tolerances now, EPA's current proposed rule 
facilitates a more-timely reflection of the actual use status within 
the tolerance regulation to provide greater clarity to stakeholders, 
including growers and States, to avoid confusion

[[Page 99189]]

about what is allowed under the FFDCA and FIFRA. Moreover, although the 
EPA's conclusions and rationale for the revocation of these tolerances 
differ from the claims outlined in the Petitioner's 2007 request to 
revoke all tolerances, the EPA is, in part, taking the action requested 
by the 2007 Petition.
    In some cases, the registrants' requests to terminate these food 
uses or cancel registered chlorpyrifos products included requests to 
continue sale, distribution, and use of existing stocks for a certain 
period of time after cancellation. Existing stocks are those stocks of 
registered pesticide products that were in the United States and that 
were packaged, labeled, and released for shipment prior to the 
effective date of the cancellation action. Under those applicable 
cancellation orders, some existing stocks of previously registered 
chlorpyrifos products may be used on food until June 30, 2025. 
Therefore, EPA is proposing that the final rule revoking the 
unnecessary tolerances set an expiration date for those tolerances 
being revoked of July 1, 2025. This approach would align the 
permissible use period allowed under the cancellation orders with the 
coverage of the existing tolerance to allow for clearer coverage under 
section 408(l)(5) of the FFDCA. Under that provision, residues of a 
pesticide chemical in or on food will not render that food adulterated 
despite the revocation of a tolerance as long as the residue is present 
as a result of a lawful application of the pesticide and does not 
exceed the tolerance level that was authorized at the time of the 
application. See 21 U.S.C. 346a(l)(5). In addition, this approach would 
provide for a reasonable interval for exporting countries to adjust to 
the new tolerance restrictions consistent with the United States' 
obligations under the World Trade Organization Agreement on the 
Application of Sanitary and Phytosanitary Measures (SPS Agreement).

IV. Safety of the Remaining Tolerances

    As noted in the previous Unit, in a typical revocation action 
following the cancellation of registered products or uses, EPA would 
propose to remove tolerances that are no longer necessary. Those 
actions typically do not require a rationale for justifying retention 
of the tolerances that are not affected by that action, as revocation 
does not impact the prior safety determinations made for the tolerances 
left in place.
    Chlorpyrifos, however, presents an unusual situation due to the 
litigation history and the pending 2007 Petition. The last formal 
determination that EPA made concerning chlorpyrifos tolerances was in 
the 2021 Final Rule, in which EPA concluded that aggregate exposure to 
chlorpyrifos, based on all registered food uses on chlorpyrifos 
products at that time, was unsafe. That rule was issued in response to 
a Ninth Circuit order, which vacated EPA's 2017 Petition Denial and 
2019 Objections Denial in full and ordered EPA to issue a final rule 
revoking all tolerances or modifying tolerances, as long as a safety 
determination supported those modified tolerances. Then the Eighth 
Circuit reinstated those tolerances through vacatur of the 2021 Final 
Rule, despite EPA's finding that those tolerances were unsafe based on 
uses that were registered at that time and noted that EPA should have 
considered the option of retaining tolerances for the 11 uses proposed 
in the 2020 PID in its 2021 Final Rule. In addition, the 2007 Petition 
asserted that all chlorpyrifos tolerances were unsafe and should be 
revoked. Because EPA's proposed rule does not revoke all chlorpyrifos 
tolerances, EPA is providing an updated determination of safety 
supporting the tolerances that are not being revoked. This approach and 
the related FIFRA cancellation actions satisfy the Eighth Circuit's 
remand for further proceedings and the Ninth Circuit's directive to 
ensure that any modified tolerances are safe, without further 
factfinding and delay.
    As indicated in Unit III., all chlorpyrifos registrants have 
submitted requests to voluntarily cancel all but 11 food uses of 
chlorpyrifos and to amend labels that limit those food uses in several 
ways, i.e., limiting uses to specific States and restricting 
application rates and application frequency. After cancellation of all 
uses but the 11 food uses listed in Unit III, amendment of those uses 
on labels as described, and the termination of existing stocks terms, 
which EPA expects no later than June 30, 2025, EPA anticipates that 
exposure to chlorpyrifos in food and drinking water will align with the 
calculations in the 2020 DWA, the 2020 human health risk assessment, 
and the proposed determinations in the 2020 PID. The cancellations and 
label amendments are reducing the amount of chlorpyrifos being used--
and thus being applied to food and getting into drinking water.
    The safety determination in this document is based on the 
anticipated aggregate exposures expected as a result of the 
cancellation of most of the registered food uses and, on the analysis 
conducted in the 2020 HH DRA and the 2020 DWA. As noted above, the 
registration review process is ongoing, and there is a possibility that 
additional information may alter the Agency's conclusions once that 
process has been completed. However, for purposes of this rule and in 
an effort not to further delay progress on this rulemaking or in 
responding to the FFDCA petition, EPA is relying on the currently 
available scientific documents to conclude that the tolerances not 
being revoked are safe, i.e., that there is a reasonable certainty that 
no harm will result from the aggregate exposure to chlorpyrifos. As 
noted in this Unit, the aggregate exposures assessed reflect the 
anticipated exposures to chlorpyrifos residues in drinking water after 
the cancellation of most food uses of chlorpyrifos, rather than 
chlorpyrifos residues in drinking water based on the wider set of 
previously registered food uses as was done in the 2021 Final Rule.
    EPA's full risk conclusions supporting this proposed response are 
set forth in Chlorpyrifos: Third Revised Human Health Risk Assessment 
for Registration Review (September 2020) (``2020 HH DRA'') and the 2020 
DWA. (Ref. 12 and 2) EPA's assessment supports a conclusion that 
aggregate exposures (including residential exposures and food and 
drinking water exposures anticipated from the remaining registered 
chlorpyrifos uses after the cancellation orders are issued and amended 
labels are approved under FIFRA) are safe.

A. EPA's Hazard Assessment for Chlorpyrifos

1. General Approach to Hazard Identification, Dose-Response Assessment, 
and Extrapolation
    Any risk assessment begins with an evaluation of a chemical's 
inherent properties, and whether those properties have the potential to 
cause adverse effects (i.e., a hazard identification). In evaluating 
toxicity or hazard, EPA reviews toxicity data, typically from studies 
with laboratory animals, to identify any adverse effects on the test 
subjects. Where available and appropriate, EPA will also take into 
account studies involving humans, including human epidemiological 
studies. The animal toxicity database for a conventional, food use 
pesticide usually consists of studies investigating a broad range of 
endpoints including potential for carcinogenicity, mutagenicity, 
developmental and reproductive toxicity, and neurotoxicity. These 
studies include gross and microscopic effects on organs and tissues, 
functional effects on bodily organs and systems, effects on blood

[[Page 99190]]

parameters (such as red blood cell (RBC) count, hemoglobin 
concentration, hematocrit, and a measure of clotting potential), 
effects on the concentrations of normal blood chemicals (including 
glucose, total cholesterol, urea nitrogen, creatinine, total protein, 
total bilirubin, albumin, hormones, and enzymes such as alkaline 
phosphatase, alanine aminotransferase and cholinesterase), and 
behavioral or other gross effects identified through clinical 
observation and measurement. EPA examines whether adverse effects are 
caused by different durations of exposure ranging from short-term 
(acute) to long-term (chronic) pesticide exposure and different routes 
of exposure (oral, dermal, inhalation). Further, EPA evaluates 
potential adverse effects in different age groups (adults as well as 
fetuses and juveniles). (Ref. 13 at 8-10).
    Once a pesticide's potential hazards are identified, EPA determines 
a toxicological level of concern for evaluating the risk posed by human 
exposure to the pesticide. In this step of the risk assessment process, 
EPA essentially evaluates the levels of exposure to the pesticide at 
which effects might occur. An important aspect of this determination is 
assessing the relationship between exposure (dose) and response (often 
referred to as the dose-response analysis). In evaluating a chemical's 
dietary risks, EPA uses a reference dose (RfD) approach, which 
typically involves a number of considerations including:
     A ``point of departure'' (PoD): Typically, the PoD is the 
value from a dose-response curve that is at the low end of the 
observable data in laboratory animals and that is the toxic dose that 
serves as the ``starting point'' in extrapolating a risk to the human 
population, although a PoD can also be derived from human data as well. 
PoDs are selected to be protective of the most sensitive adverse toxic 
effect for each exposure scenario and are chosen from toxicity studies 
that show clearly defined No Observed Adverse Effect Levels (NOAELs) or 
Lowest Observed Adverse Effect Levels (LOAELs), dose-response 
relationships, and relationships between the chemical exposure and 
effect. EPA will select separate PoDs, as needed, for each expected 
exposure duration (e.g., acute, chronic, short-term, intermediate-term) 
and route of exposure (e.g., oral, dermal, inhalation). For 
chlorpyrifos, as discussed later in this Unit, EPA derived PoDs based 
on 10% RBC AChE inhibition in the 2020 HH DRA.
     Interspecies extrapolation: Because most PoDs are derived 
from toxicology studies in laboratory animals, there is a need to 
extrapolate from animals to humans. In typical risk assessments, a 
default tenfold (10X) uncertainty factor is used to address the 
potential for a difference in toxic response between humans and animals 
used in toxicity tests. For chlorpyrifos, as described further below, 
EPA used a sophisticated model called a physiologically based 
pharmacokinetic-pharmacodynamic (PBPK-PD) model that accounts for 
differences in laboratory animals and humans, thereby obviating the 
need for the default interspecies factor.
     Intraspecies extrapolation: To address the potential for 
differences in sensitivity in the toxic response across the human 
population, EPA conducts intraspecies extrapolation. In typical risk 
assessments, a 10X default uncertainty factor is used. For 
chlorpyrifos, the PBPK-PD model used to derive PoDs also accounts for 
differences in metabolism and toxicity response across the human 
population for some age groups and some subpopulations, which allows 
the default factor of 10X to be refined in accordance with EPA's 2014 
Guidance for Applying Quantitative Data to Develop Data-Derived 
Extrapolation Factors for Interspecies and Intraspecies Extrapolation.
     Food Quality Protection Act safety factor (FQPA SF): The 
FFDCA section 408(b)(2)(C) instructs EPA, in making its ``reasonable 
certainty of no harm'' finding, that in ``the case of threshold 
effects, an additional tenfold margin of safety for the pesticide 
chemical residue and other sources of exposure shall be applied for 
infants and children to take into account potential pre- and post-natal 
toxicity and completeness of data with respect to exposure and toxicity 
to infants and children.'' Section 408(b)(2)(C) further states that 
``the Administrator may use a different margin of safety for the 
pesticide chemical residue only if, on the basis of reliable data, such 
margin will be safe for infants and children.'' For chlorpyrifos, EPA 
is retaining the default 10X FQPA SF as discussed later in this Unit.
    In the human health risk assessment process, as indicated above, 
EPA uses the selected PoD to calculate a RfD for extrapolating risk. 
The RfD is calculated by dividing the selected PoD by any applicable 
interspecies and intraspecies factors and other relevant uncertainty 
factors such as LOAEL to NOAEL factor or database uncertainty factor.
    After calculating the RfD, as indicated above, EPA retains an 
additional safety factor of 10X to protect infants and children (the 
FQPA SF), unless reliable data support selection of a different factor, 
as required under the FFDCA. As described in EPA's policy for 
determining the appropriate FQPA SF, this additional safety factor 
often overlaps with other traditional uncertainty factors (e.g., LOAEL 
to NOAEL factor or database uncertainty factor), but it might also 
account for residual concerns related to pre- and post-natal toxicity 
or exposure. (Ref. 14 at 13-16) In implementing FFDCA section 408, EPA 
calculates a variant of the RfD referred to as a Population Adjusted 
Dose (PAD), by dividing the RfD by the FQPA SF. Risk estimates less 
than 100% of the PAD are safe.
2. Toxicological Effects of Chlorpyrifos
    Consistent with FFDCA section 408(b)(2)(D), EPA has reviewed the 
available scientific data and other relevant information for 
chlorpyrifos in support of this action. For over two decades, EPA has 
evaluated the scientific evidence surrounding the different health 
effects associated with chlorpyrifos. The Agency has conducted 
extensive reviews of the scientific literature on health outcomes 
associated with chlorpyrifos and presented approaches for evaluating 
and using that information to the FIFRA Scientific Advisory Panel 
(SAP), on several occasions, as discussed in Unit V of the 2021 Final 
Rule. See 86 FR at 48320-21. (Note: The FIFRA SAP is a federal advisory 
committee created by FIFRA section 25(d), 7 U.S.C. 136w(d), and serves 
as EPA's primary source of external, independent, scientific peer 
review for significant regulatory and policy matters involving 
pesticides).
    Chlorpyrifos has been tested in toxicological studies for the 
potential to cause numerous different adverse outcomes (e.g., 
reproductive toxicity, developmental toxicity, cancer, genotoxicity, 
dermal toxicity, endocrine toxicity, inhalation toxicity, and 
immunotoxicity). Chlorpyrifos has an established neurotoxic mode of 
action, and neurotoxicity is the most sensitive effect in all species, 
routes, and lifestages. The hazard characterization for chlorpyrifos 
and its oxon is based on adverse health effects in animals and humans 
related to two different neurotoxic endpoints: AChE inhibition and 
potential for neurodevelopmental effects. AChE inhibition is being used 
to derive the PODs for risk assessment. These PODs are protective for 
neurotoxic effects related to AChE inhibition and potential downstream 
neurotoxic effects. A weight-of-the-evidence (WOE) analysis on the 
potential for neurodevelopmental effects following chlorpyrifos 
exposure considered (1) whether chlorpyrifos

[[Page 99191]]

causes long-term effects from prenatal and/or early lifestage exposure 
and (2) whether adverse effects can be attributed to doses lower than 
those which elicit 10% inhibition of RBC AChE. (Ref. 12 at 6) The FIFRA 
SAP reports have rendered numerous recommendations for additional study 
and sometimes conflicting advice for how EPA should consider (or not 
consider) the available data in conducting EPA's registration review 
human health risk assessment for chlorpyrifos.
    The remainder of this Unit IV.A.2. discusses the Agency's 
assessment of the science relating to AChE inhibition and the potential 
for neurodevelopmental effects. Other adverse outcomes besides AChE 
inhibition and neurodevelopment are less sensitive and are thus not 
discussed in detail here. Further information concerning those effects 
can be found in the 2000 human health risk assessment which supported 
the RED and the 2011 preliminary human health risk assessment. (Ref. 15 
and 16).
a. Acetylcholinesterase (AChE) Inhibition
    Chlorpyrifos, like other organophosphate pesticides, affects the 
nervous system by inhibiting AChE, an enzyme necessary for the proper 
functioning of the nervous system and ultimately leading to signs of 
neurotoxicity. This mode of action, in which AChE inhibition leads to 
neurotoxicity, is well-established, and thus has been used as basis for 
the PoD for organophosphate human health risk assessments, including 
chlorpyrifos. This science policy is based on decades of work, which 
shows that AChE inhibition is the initial event in the pathway to 
cholinergic neurotoxicity.
    The Agency has conducted a comprehensive review of the available 
data and public literature regarding this adverse effect from 
chlorpyrifos. (Ref. 17 at 24-25, Ref. 16 at 25-27) There are many 
chlorpyrifos studies evaluating RBC AChE inhibition or the brain in 
multiple lifestages (gestational, fetal, post-natal, and non-pregnant 
adult), multiple species (rat, mouse, rabbit, dog, human), methods of 
oral administration (oral gavage with corn oil, dietary, gavage via 
milk) and routes of exposure (oral, dermal, inhalation via vapor and 
via aerosol). In addition, chlorpyrifos is unique in the availability 
of AChE data from peripheral tissues in some studies (e.g., heart, 
lung, liver). There are also literature studies comparing the in vitro 
AChE response to a variety of tissues which show similar sensitivity 
and intrinsic activity. Across the database, brain AChE tends to be 
less sensitive than RBC AChE or peripheral AChE. In oral studies, RBC 
AChE inhibition is generally similar in response to peripheral tissues. 
Thus, the in vitro data and oral studies combined support the continued 
use of RBC AChE inhibition as the critical effect for quantitative 
dose-response assessment.
    For chlorpyrifos, there are data from multiple studies which 
provide robust RBC AChE data, including studies in pregnant, lactating, 
and non-pregnant female rats from oral exposure (e.g., developmental 
neurotoxicity (DNT), reproductive, and subchronic data). In addition, 
studies are available in juvenile pups that show age-dependent 
differences, particularly following acute exposures, in sensitivity to 
chlorpyrifos and its oxon metabolite. This sensitivity is not derived 
from differences in the AChE enzyme itself but instead are derived 
largely from the immature metabolic clearance capacity in the 
juveniles.
b. Neurodevelopmental Toxicity
    In addition to information on the effects of chlorpyrifos on AChE, 
there is an extensive body of information (in the form of laboratory 
animal studies, epidemiological studies, and mechanistic studies) 
studying the potential effects on neurodevelopment in infants and 
children following exposure to organophosphates, including 
chlorpyrifos.
    There are numerous laboratory animal studies on chlorpyrifos in the 
literature that have evaluated the impact of chlorpyrifos exposure in 
pre- and post-natal dosing on the developing brain. These studies vary 
substantially in their study design, but all involve gestational and/or 
early post-natal dosing with behavioral evaluation from adolescence to 
adulthood. The data provide qualitative support for chlorpyrifos to 
potentially impact the developing mammalian brain with adverse outcomes 
in several neurological domains including cognitive, anxiety and 
emotion, social interactions, and neuromotor function. It is, however, 
important to note that there is little consistency in patterns of 
effects across studies. In addition, most of these studies use doses 
that far exceed EPA's 10% benchmark response level for RBC AChE 
inhibition. There are only a few studies with doses at or near the 10% 
brain or RBC AChE inhibition levels; among these only studies from Carr 
laboratory at Mississippi State University are considered by EPA to be 
high quality. In the 2020 HH DRA, EPA concluded that the laboratory 
animal studies on neurodevelopmental outcomes are not sufficient for 
quantitatively establishing a PoD. EPA further concluded that the 
laboratory animal studies do not support a conclusion that adverse 
neurodevelopmental outcomes are more sensitive than 10% RBC AChE 
inhibition. (Ref. 17 at 25-31, Ref. 12 at 88-89).
    EPA evaluated numerous epidemiological studies on chlorpyrifos and 
other organophosphate pesticides in accordance with the ``Framework for 
Incorporating Human Epidemiologic & Incident Data in Health Risk 
Assessment.'' (Ref. 17, 18, and 19) The most robust epidemiologic 
research comes from three prospective birth cohort studies. These 
include: (1) The Mothers and Newborn Study of North Manhattan and South 
Bronx performed by the Columbia Children's Center for Environmental 
Health (CCCEH) at Columbia University; (2) the Mount Sinai Inner-City 
Toxicants, Child Growth and Development Study or the ``Mt. Sinai Child 
Growth and Development Study;'' and (3) the Center for Health 
Assessment of Mothers and Children of Salinas Valley (CHAMACOS) 
conducted by researchers at University of California Berkeley. (Ref. 17 
at 32-43).
    In the case of the CCCEH study, which specifically evaluated the 
possible connections between chlorpyrifos levels in cord blood and 
neurodevelopmental outcomes on a specific cohort, there are a number of 
notable associations. (Ref. 17 at 36-38) Regarding infant and toddler 
neurodevelopment, the CCCEH authors reported statistically significant 
deficits of 6.5 points on the Psychomotor Development Index at three 
years of age when comparing high to low exposure groups. Notably, these 
decrements persist even after adjustment for group and individual level 
socioeconomic variables. These investigators also observed increased 
odds of mental delay and psychomotor delay at age three when comparing 
high to low exposure groups. The CCCEH authors also report strong, 
consistent evidence of a positive association for attention disorders, 
attention deficit hyperactivity disorder (ADHD), and pervasive 
development disorder (PDD) when comparing high to low chlorpyrifos 
exposure groups. Moreover, it was reported that for children in the 
CCCEH cohort at age seven for each standard deviation increase in 
chlorpyrifos cord blood exposure, there is a 1.4% reduction in Full-
Scale IQ and a 2.8% reduction in Working Memory. In addition, the CCCEH 
authors evaluated the relationship between pre-natal

[[Page 99192]]

chlorpyrifos exposure and motor development/movement and reported 
elevated risks of arm tremor in children around 11 years of age in the 
CCCEH cohort.
    Notwithstanding the observed associations, EPA and the 2012 and 
2016 FIFRA SAP reports identified multiple uncertainties in the CCCEH 
epidemiology studies. (Ref. 17 and 20) Some of these include the 
relatively modest sample sizes, which limited the statistical power; 
exposure at one point in pre-natal time with no additional information 
regarding post-natal exposures; representativeness of a single point 
exposure where time-varying exposures or the ability to define 
cumulative exposures would be preferable; lack of specificity of a 
critical window of effect and the potential for misclassification of 
individual exposure measures; and lack of availability of the raw data 
from the studies that would allow verification of study conclusions.
    One of the notable uncertainties in the CCCEH epidemiology studies 
identified by EPA and the 2016 FIFRA SAP report is the lack of specific 
exposure information on the timing, frequency, and magnitude of 
chlorpyrifos application(s) in the apartments of the women in the 
study. Since 2012, despite extensive effort by EPA to obtain or infer 
this exposure information from various sources, the lack of specific 
exposure data remains a critical uncertainty. EPA made efforts in 2014 
and 2016 to develop dose reconstruction of the exposures to these 
women. These dose reconstruction activities represent the best 
available information and tools but are highly uncertain. In addition, 
the pregnant women and children in the CCCEH studies were exposed to 
multiple chemicals, including multiple potent AChE-inhibiting 
organophosphates and N-methyl carbamates. Moreover, using EPA's dose 
reconstruction methods from 2014 suggest that the pregnant women likely 
did not exhibit RBC AChE inhibition above 10%. The 2012 and 2016 FIFRA 
SAP reports expressed concern that it is likely that the CCCEH findings 
occurred at exposure levels below those that result in 10% RBC AChE 
inhibition. (Ref. 17 and 20) However, given the limitations of the 
available CCCEH exposure information and the exposures to multiple 
potent AChE inhibiting pesticides, EPA has been unable to definitively 
conclude the level of AChE inhibition occurring in the CCCEH studies. 
Consistent with the 2016 SAP report, EPA remains unable to make a 
causal linkage between chlorpyrifos exposure and the outcomes reported 
by CCCEH investigators. (Ref. 12 and 17) Given the uncertainties, 
particularly in the exposure information available from CCCEH (single 
timepoints, lack of time varying exposure, lack of knowledge about 
application timing), uncertainties remain about the dose-response 
relationships from the epidemiology studies, which EPA noted in the 
2020 HH DRA. (Ref. 12)
    Finally, there are several lines of evidence for modes of action of 
chlorpyrifos distinct from the classical mode of action of AChE 
inhibition. This information has been generated from model systems 
representing different levels of biological organization and provide 
support for molecular initiating events (binding to the morphogenic 
site of AChE, muscarinic receptors, or tubulin), cellular responses 
(alterations in neuronal proliferation, differentiation, neurite 
growth, or intracellular signaling), and responses at the level of the 
intact nervous system (serotonergic tone, axonal transport). Among the 
many in vitro studies on endpoints relevant to the developing brain 
available for chlorpyrifos, only three have identified outcomes in 
picomole concentrations, including concentrations lower than those that 
elicit AChE inhibition in vitro. However, as is the case for many other 
developmental neurotoxicants, most of these studies have not been 
designed with the specific goal of construction or testing an adverse 
outcome pathway. Thus, as discussed in the 2020 HHRA, there are not 
sufficient data available to test rigorously the causal relationship 
between effects of chlorpyrifos at the different levels of biological 
organization in the nervous system. (Ref. 17 at 27-31), so until there 
are any updates to the state of the science for chlorpyrifos, the 
Agency is relying on the 2020 HHRA for this rule.
3. Hazard Identification: Using AChE as the Toxicological Endpoint for 
Deriving PADs
    In its 2020 HH DRA assessment, based on its review of all available 
data, EPA determined that AChE inhibition has the most robust 
quantitative dose-response data and, thus, was chosen as the critical 
effect for the quantitative risk assessment. The Agency typically uses 
a 10% response level for AChE inhibition in human health risk 
assessments. This longstanding approach, see 2006 RED, is consistent 
with the advice of the FIFRA SAP from 2008 and 2012 and has been 
applied in the 2006 OP cumulative risk assessment and other single-
chemical OP risk assessments. (Ref. 21 and 22).
    During the ongoing registration review of chlorpyrifos and 
consideration of the 2007 Petition, the Agency has received comments 
concerning whether the use of the 10% AChE inhibition is sufficiently 
health protective. In one effort to take those comments into 
consideration, EPA conducted an additional hazard analysis and convened 
the 2016 FIFRA SAP to evaluate a proposal of using cord blood data from 
the CCCEH epidemiology studies as the source of data for PoDs. The 2016 
FIFRA SAP report did not support the ``direct use'' of the cord blood 
and working memory data for deriving the regulatory endpoint, due to 
insufficient information about timing and magnitude of chlorpyrifos 
applications in relation to cord blood concentrations at the time of 
birth, uncertainties about the pre-natal window(s) of exposure linked 
to reported effects, and lack of a second laboratory to reproduce the 
analytical blood concentrations. (Ref. 17) Despite their critiques 
regarding uncertainties in the CCCEH studies, the 2016 FIFRA SAP report 
expressed concern that 10% RBC AChE inhibition may not be sufficiently 
protective of human health.
    The 2016 FIFRA SAP report, however, did present an alternative 
approach for EPA to consider. This report was supportive of EPA's use 
of the PBPK-PD model as a tool for assessing internal dosimetry from 
typical pesticide exposure scenarios. Use of the PBPK-PD model coupled 
with typical exposure scenarios provides the strongest scientific 
foundation for chlorpyrifos human health risk assessment. Given that 
the window(s) of susceptibility are currently not known for the 
observed neurodevelopmental effects, and the uncertainties associated 
with quantitatively interpreting the CCCEH cord blood data, the 2016 
FIFRA SAP report recommended that the Agency use a time weighted 
average (TWA) blood concentration of chlorpyrifos for the CCCEH study 
cohort as the PoD for risk assessment. Thus, in 2016, EPA attempted, 
using the PBPK-PD model, to determine the TWA blood level expected from 
post-application exposures from the chlorpyrifos indoor crack-and-
crevice use scenario. Despite that effort, EPA concluded in the 2020 HH 
DRA that the shortcomings of the data with regard to the dose-response 
relationship and lack of exposure information discussed above, continue 
to raise issues that make quantitative use of the CCCEH data in risk 
assessment not scientifically sound. (Ref. 12)
    Thus, taking into consideration the robustness of the available 
data at this

[[Page 99193]]

time, EPA has determined in the 2020 HH DRA that the most appropriate 
toxicological endpoint for deriving points of departure for assessing 
risks of chlorpyrifos is 10% RBC AChE inhibition. The Agency is not 
ignoring or dismissing the extensive data concerning the potential for 
adverse neurodevelopmental outcomes. As discussed later in this Unit, 
the Agency is addressing the uncertainties surrounding the potential 
for adverse neurodevelopmental outcomes by retaining the default 10X 
FQPA SF.
a. Durations of Exposure
    As noted in Unit IV.A.1., EPA establishes PoDs for each expected 
exposure duration likely to result from pesticide exposure. For 
chlorpyrifos, exposure can occur from a single event or on a single day 
or from repeated days of exposure. With respect to AChE inhibition, 
effects can occur from a single exposure or from repeated exposures. 
For organophosphates, repeated exposures generally result in more AChE 
inhibition at a given administered dose compared to acute exposures. 
Moreover, AChE inhibition in repeated dosing guideline toxicology 
studies with most organophosphates show a consistent pattern of 
inhibition reaching a ``steady state'' of inhibition at or around 2 to 
3 weeks of exposure in adult laboratory animals. (Ref. 23) This pattern 
observed with repeated dosing is a result of the amount of inhibition 
coming to equilibrium with production of new enzyme. As such, AChE 
studies of 2 to 3 weeks generally show the same degree of inhibition 
with those of longer duration (i.e., up to two years of exposure). 
Thus, for most of the human health risk assessments for the 
organophosphates, the Agency is focusing on the critical durations 
ranging from a single day up to 21 days (i.e., the approximate time to 
reach steady state for most organophosphates). As such, EPA has 
calculated PoDs for the acute and steady-state durations. As described 
below, these PoDs have been derived for various lifestages, routes, and 
exposure scenarios.
b. Deriving PoDs, Interspecies and Intraspecies Extrapolation: Use of 
the PBPK Model
    The process for developing RfDs and PADs typically involves first 
deriving PoDs directly from laboratory animal studies, followed by 
dividing the PoD by the default uncertainty factors of 10X each for 
interspecies extrapolation and intraspecies extrapolation, and the FQPA 
safety factor. For chlorpyrifos, EPA has developed a sophisticated 
PBPK-PD model to derive PoDs. Numerous federal advisory committees and 
external review panels have encouraged the use of such a modeling 
approach to reduce inherent uncertainty in the risk assessment and 
facilitate more scientifically sound extrapolations across studies, 
species, routes, and dose levels. The PBPK-PD model for chlorpyrifos 
has undergone extensive peer review by various individual or groups, 
including the FIFRA SAPs. Significant improvements have been made to 
the model over the years in response to recommendations from the 2008, 
2011, and 2012 FIFRA SAPs and comments from both internal and external 
peer reviewers. (Ref. 12 at 20) As a result, EPA has concluded that the 
current PBPK-PD model is sufficiently robust and is using it for 
deriving PoDs for chlorpyrifos.
i. Derivation of PoDs
    As noted above, the PoDs for chlorpyrifos are based on the levels 
at which 10% RBC AChE inhibition is observed. The PBPK-PD model 
accounts for pharmacokinetic and pharmacodynamic characteristics to 
derive age, duration, and route-specific PoDs. Separate PoDs have been 
calculated for dietary (food, drinking water) and residential exposures 
by varying inputs on types of exposures and populations exposed. 
Specifically, the following characteristics have been evaluated: (1) 
Duration (24-hour (acute), 21-day (steady-state)); (2) route (dermal, 
oral, inhalation); (3) body weights which vary by lifestage; (4) 
exposure duration (hours per day, days per week); and (5) exposure 
frequency (events per day (eating, drinking)). For each exposure 
scenario, the appropriate body weight for each age group or sex was 
modeled as identified from the Exposure Factors Handbook for 
residential exposures and from the U.S. Department of Agriculture's 
(USDA) National Health and Nutrition Examination Survey (NHANES)/What 
We Eat in America (WWEIA) Survey for dietary exposures. (Ref. 24).
    Using the PBPK-PD model, the Agency evaluated the following 
exposure scenarios: (1) drinking water exposures to oxon (chlorpyrifos 
metabolite)--acute and steady-state exposures for infants, children, 
youths, and female adults; (2) food exposures to chlorpyrifos--acute 
and steady-state exposures for infants, children, youths, and female 
adults; (3) residential dermal exposures to chlorpyrifos--steady-state 
exposures for children, youths, and female adults; (4) residential 
hand-to-mouth ingestion exposures--steady-state for children 1 to 2 
years old; and (5) residential inhalation exposures--steady-state for 
children 1 to 2 years old and female adults. (Ref. 12 at 22-25).
    Steady-state dietary exposure was estimated daily for 21 days. For 
drinking water exposure, infants and young children (infants <1 year 
old, children between 1 to 2 years old, and children between 6 to 12 
years old) were assumed to consume water 6 times per day, with a total 
consumption volume of 0.69 L/day. For youths and female adults, they 
were assumed to consume water 4 times per day, with a total consumption 
volume of 1.71 L/day.
    For all residential dermal exposures to chlorpyrifos, the dermal 
PoDs were estimated assuming 50% of the skin's surface was exposed. 
Exposure times for dermal exposure assessment were consistent with 
those recommended in the 2012 Residential Standard Operating Procedures 
(SOPs). (Ref. 22) For residential inhalation exposures following public 
health mosquitocide application, the exposure duration was set to 1 
hour per day for 21 days. The incidental oral PoDs for children 1 to <2 
years old for other turf activities were estimated assuming that there 
were six events, 15 minutes apart, per day.
    The PBPK-modeled PoDs derived for the various lifestages, routes, 
and exposure scenarios discussed above, can be found in table 4.2.2.1.2 
of the 2020 HH DRA. (Ref. 12).
ii. Interspecies Extrapolation
    As indicated above, the PBPK-PD model directly predicts human PoDs 
based on human physiology and biochemistry; thus, there is no need for 
an interspecies uncertainty factor to extrapolate from animal PoDs.
iii. Intraspecies Extrapolation
    The PBPK-PD model can account for variability of critical 
physiological, pharmacokinetic, and pharmacodynamic parameters in a 
population to estimate, using the Monte Carlo analysis, the 
distribution of doses that result in 10% RBC AChE inhibition. 
Therefore, Data-Derived Extrapolation Factors (DDEF) for intraspecies 
extrapolation have been estimated to replace the default intraspecies 
uncertainty factor for some groups. (Ref. 25).
    According to EPA's DDEF guidance, when calculating a DDEF 
intraspecies extrapolation factor, administered doses leading to the 
response level of interest (in the case of chlorpyrifos, the 10% change 
in RBC AChE inhibition) are compared between a measure of average 
response and response at the tail of the distribution representing 
sensitive individuals. The tail of the distribution

[[Page 99194]]

may be selected at the 95th, 97.5th, and 99th percentile.
    As for chlorpyrifos, the 99th percentile was used in risk 
assessment to provide the most conservative measure. (Ref. 26) In 
addition to estimating DDEF using the above approach for specific age 
groups, intraspecies DDEF were also calculated by comparing average 
responses between adults and 6-month-old infants. For the 2020 HHRA, 
the largest calculated DDEFs, 4X for chlorpyrifos and 5X for the oxon 
metabolite, were used for intraspecies extrapolation for all groups 
except women of childbearing age. There was a slightly higher 
variability between adults and infants when considering the 
distributions for the oxon metabolite, thus, the slightly higher 
intraspecies factor. For women of childbearing age, the Agency is 
applying the standard 10X intraspecies extrapolation factor due to 
limitations in the PBPK-PD model to account for physiological, 
anatomical, and biochemical changes associated with pregnancy. (Ref. 12 
at 21-22).
iv. Summarizing the PoDs, Interspecies and Intraspecies Extrapolation 
Factors
    In summary, for assessing the risks from exposure to chlorpyrifos, 
the human PBPK-PD model has been used to derive PoDs based on 10% RBC 
AChE inhibition for various populations, durations, and routes. The 
model, which calculates a human PoD directly, obviates the need for an 
interspecies extrapolation factor since animal data are not used. To 
account for variations in sensitivities, the Agency has determined that 
an intraspecies factor of 4X for chlorpyrifos and 5X for the oxon is 
appropriate for all groups except women of childbearing age. For women 
of childbearing age, the typical 10X intraspecies factor is being 
applied, due the lack of appropriate information and algorithms to 
characterize physiological changes during pregnancy.
c. FQPA Safety Factor
    As noted above, the FFDCA requires EPA, in making its safety 
finding, that in ``the case of threshold effects, an additional tenfold 
margin of safety for the pesticide chemical residue and other sources 
of exposure shall be applied for infants and children to take into 
account potential pre- and post-natal toxicity and completeness of data 
with respect to exposure and toxicity to infants and children.'' 21 
U.S.C. 346a(b)(2)(C). Section 408(b)(2)(C) further states that ``the 
Administrator may use a different margin of safety for the pesticide 
chemical residue only if, on the basis of reliable data, such margin 
will be safe for infants and children.'' Id.
    In applying the FQPA SF provision, EPA has interpreted it as 
imposing a presumption in favor of retaining it as an additional 10X 
SF. (Ref. 27 at 4, 11) Thus, EPA generally refers to the 10X factor as 
a presumptive or default 10X factor. EPA has also made clear, however, 
that this presumption or default in favor of the 10X is only a 
presumption. The presumption can be overcome if reliable data 
demonstrate that a different factor is safe for children. (Id.). In 
determining whether a different factor is safe for children, EPA 
focuses on the three factors listed in FFDCA section 408(b)(2)(C)--the 
completeness of the toxicity database, the completeness of the exposure 
database, and potential pre- and post-natal toxicity. In examining 
these factors, EPA strives to make sure that its choice of a SF, based 
on a weight-of-the-evidence evaluation, does not understate the risk to 
children. (Id. at 24-25, 35).
    In the 2020 HH DRA, the default 10X FQPA SF was retained, and the 
assessment did not adopt or offer support for reducing the factor to 
1X. However, the 2020 HH DRA does present potential risks from 
exposures to chlorpyrifos with retention of the default 10X FQPA SF and 
with reduction of the FQPA SF to 1X. The purpose of presenting both 
values was to provide an indication of what the potential risk 
estimates would be under either scenario. To reduce the FQPA SF to 1X, 
the FFDCA requires that EPA determine that reliable data demonstrate 
that the 1X would be safe for infants and children. The 2020 HH DRA did 
not make that determination. For chlorpyrifos, of the three factors 
mentioned in the previous paragraph, the primary factor that undercuts 
a determination that a different SF would be safe for children is the 
uncertainty around the potential for pre- and post-natal toxicity for 
infants and children in the area of neurodevelopmental outcomes.
    Based on the weight of the evidence concerning the potential for 
neurodevelopmental outcomes as discussed in this Unit above, there is 
ample qualitative evidence of a potential effect on the developing 
brain; however, there remains uncertainty around the levels at which 
these potential neurodevelopmental outcomes occur. Although the 
laboratory animal studies do not support a conclusion that 
neurodevelopmental outcomes are more sensitive than AChE inhibition, 
there remains some uncertainty in the dose-response relationship 
between chlorpyrifos and adverse neurodevelopmental outcomes based on 
the epidemiology data, and the mechanistic data are, at this time, 
incomplete in their characterization of dose-response. Because the data 
available at this time indicate remaining uncertainties concerning pre- 
and post-natal toxicity due to insufficient clarity on the levels at 
which these outcomes occur, the Agency is unable to conclude, at this 
time, that a different SF would be safe for infants and children. Thus, 
the Agency is retaining the default 10X FQPA SF at this time.
d. Total Uncertainty Factors and PADs
    In conclusion, the Agency used a total uncertainty factor of 100X 
for determining the food and drinking water PADs for females of 
childbearing age (1X interspecies factor, 10X intraspecies factor, and 
10X FQPA SF); 40X for determining the food PADs for remaining 
populations (1X interspecies factor, 4X intraspecies factor, and 10X 
FQPA SF); and 50X for determining the PADs for drinking water for 
remaining populations (1X interspecies factor, 5X intraspecies factor, 
and 10X FQPA SF).
    Taking into consideration the PoDs, intraspecies extrapolation 
factors, and FQPA SF, the Agency calculated acute PADs (aPADs) and 
steady-state PADs (ssPADs) for infants (less than 1 year old), children 
(1 to 2 years old), children/youth (6 to 12 years old), and females (13 
to 49 years old); these subpopulations will be protective of other 
subpopulations. While PADs were calculated for youths (13 to 19 years 
old), these PADs were not used in the dietary/aggregate assessments 
because females (13 to 49 years old) are considered protective of this 
sub-population. (Ref. 12 at 30-32) Risk estimates can be found in table 
5.0.1 in the 2020 HH DRA.

B. EPA's Exposure Assessment for Chlorpyrifos

    Risk is a function of both hazard and exposure. Thus, equally 
important to the risk assessment process as determining the hazards 
posed by a pesticide and the toxicological endpoints for those hazards 
is estimating human exposure. Under FFDCA section 408, EPA must 
evaluate the aggregate exposure to a pesticide chemical residue, which 
includes ``all anticipated dietary exposures and all other exposures 
for which there is reliable information.'' 21 U.S.C. 346a(b)(2)(A)(ii). 
This means that EPA is concerned not only with exposure to pesticide 
residues in food but also exposure resulting from pesticide 
contamination of drinking water

[[Page 99195]]

supplies and from use of pesticides in the home or other non-
occupational settings. (See 21 U.S.C. 346a(b)(2)(D)(vi)).
    Pursuant to FFDCA section 408(b), EPA has evaluated chlorpyrifos's 
risks based on ``aggregate exposure'' to chlorpyrifos. By ``aggregate 
exposure,'' EPA is referring to exposure to chlorpyrifos by multiple 
pathways of exposure, i.e., food, drinking water, and residential. EPA 
uses available data and standard analytical methods, together with 
assumptions designed to be protective of public health, to produce 
separate estimates of exposure for a highly exposed subgroup of the 
general population, for each potential pathway and route of exposure.
    The following analysis reflects a summary of the Agency's exposure 
assessment from the 2020 HH DRA unless otherwise specified. (Ref. 2).
1. Exposure From Food
a. General Approach for Estimating Food Exposures
    There are two critical variables in estimating exposure in food: 
(1) the types and amount of food that is consumed; and (2) the residue 
level in that food. Consumption is estimated by EPA based on scientific 
surveys of individuals' food consumption in the United States conducted 
by the U.S. Department of Agriculture (USDA). (Ref. 28 at 12) 
Information on residue values can come from a range of sources 
including crop field trials; data on pesticide reduction (or 
concentration) due to processing, cooking, and other practices; 
information on the extent of usage of the pesticide; and monitoring of 
the food supply. (Id. at 17).
    Data on the residues of chlorpyrifos in foods are available from 
both field trial data and monitoring data, primarily the USDA's 
Pesticide Data Program (PDP) monitoring data. Monitoring data generally 
provide a characterization of pesticide residues in or on foods 
consumed by the U.S. population that closely approximates real-world 
exposures because they are sampled closer to the point of consumption 
in the chain of commerce than field trial data, which are generated to 
establish the maximum level of legal residues that could result from 
maximum permissible use of the pesticide immediately after harvest.
    EPA used a computer program known as the Dietary Exposure 
Evaluation Model and Calendex software with the Food Commodity Intake 
Database (DEEM-FCID version 3.16/Calendex) to estimate chlorpyrifos 
exposure by combining data on human consumption amounts with residue 
values in food commodities. This version of the model incorporated 
2003-2008 consumption data from USDA's NHANES/WWEIA. The data are based 
on the reported consumption of more than 20,000 individuals over two 
non-consecutive survey days. Foods ``as consumed'' (e.g., apple pie) 
are linked to EPA-defined food commodities (e.g., apples, peeled 
fruit--cooked; fresh or N/S (Not Specified); baked; or wheat flour--
cooked; fresh or N/S, baked) using publicly available recipe 
translation files developed jointly by USDA Agricultural Research 
Service (ARS) and EPA. For chronic exposure assessment (or in the case 
of chlorpyrifos, for steady-state exposure assessment), consumption 
data are averaged for the entire U.S. population and within population 
subgroups; however, for acute exposure assessment, consumption data are 
retained as individual consumption events. Using this consumption 
information and residue data, the exposure estimates are calculated for 
the general U.S. population and specific subgroups based on age, sex, 
ethnicity, and region.
    For chlorpyrifos, EPA determined that acute and steady-state 
exposure durations were relevant for assessing risk from food 
consumption. EPA calculates potential risk by using probabilistic 
techniques to combine distributions of potential exposures in sentinel 
populations. The resulting probabilistic assessments present a range of 
dietary exposure/risk estimates.
    Because probabilistic assessments generally present a realistic 
range of residue values to which the population may be exposed, EPA's 
starting point for estimating exposure and risk for such assessments is 
the 99.9th percentile of the population under evaluation. When using a 
probabilistic method of estimating acute dietary exposure, EPA 
typically assumes that, when the 99.9th percentile of acute exposure is 
equal to or less than the aPAD, the level of concern for acute risk has 
not been exceeded. By contrast, where the analysis indicates that 
estimated exposure at the 99.9th percentile exceeds the aPAD, EPA would 
generally conduct one or more sensitivity analyses to determine the 
extent to which the estimated exposures at the high-end percentiles may 
be affected by unusually high food consumption or residue values. (The 
same assumptions apply to estimates for steady-state dietary exposure 
and the ssPAD.) To the extent that one or a few values seem to 
``drive'' the exposure estimates at the high-end of exposure, EPA would 
consider whether these values are reasonable and should be used as the 
primary basis for regulatory decision making. (Ref. 29).
b. Estimating Chlorpyrifos Exposures in Food
    The residue of concern, for tolerance expression and risk 
assessment, in plants (food and feed) and livestock commodities is the 
parent compound chlorpyrifos. EPA has determined that the metabolite 
chlorpyrifos oxon is not a residue of concern in food or feed, based on 
available field trial data and metabolism studies that indicate that 
the oxon is not present in the edible portions of the crops. This 
conclusion is supported by USDA PDP monitoring data, which did not find 
residues of chlorpyrifos oxon on food samples. Furthermore, the oxon 
metabolite was not found in milk or livestock tissues. (Ref. 12 at 33).
    Acute and steady-state dietary (food only) exposure analyses for 
chlorpyrifos were conducted using the DEEM-FCID version 3.16/Calendex 
software. (Ref. 30) These analyses were performed for the purpose of 
obtaining food exposure values for comparison to the chlorpyrifos doses 
predicted by the PBPK-PD model to cause 10% RBC AChE inhibition. The 
acute and steady-state dietary (food only) exposure analyses do not 
include drinking water exposures, which were assessed separately, as 
discussed in the next section.
    The assessments include exposures to residues on all field crops 
and livestock use resulting from uses registered at the time of the 
dietary risk assessment as well as residues on imported commodities, 
but the assessments do not include potential exposure from food 
handling establishments as those were considered negligible. (Ref. 26) 
Both the acute and steady-state dietary (food only) exposure analyses 
are highly refined. The large majority of food residues used were based 
upon PDP monitoring data except in a few instances where no appropriate 
PDP data were available. In those cases, field trial data or tolerance-
level residues were assumed. EPA also used food-processing factors from 
submitted studies as appropriate. In addition, EPA's acute and steady-
state dietary (food only) exposure assessments used percent crop 
treated (PCT) information. (Ref. 30).
    The chlorpyrifos acute dietary (food only) exposure analysis was 
conducted using the DEEM-FCID, version 3.16. The acute risk estimates 
were presented for the sentinel populations for infants (less than 1 
year old); children (1-2 years old); youths (6-12 years old); and

[[Page 99196]]

adults (females 13-49 years old). The assessment of these index 
lifestages is protective of other population subgroups.
    The chlorpyrifos steady-state dietary (food only) exposure analysis 
was conducted using the Calendex component of DEEM-FCID (with 2003-2008 
survey consumption data from USDA's NHANES/WWEIA). Calendex provides a 
focus detailed profile of potential exposures to individuals across a 
calendar year. A calendar-based approach provides the ability to 
estimate daily exposures from multiple sources over time to an 
individual and is in keeping with two key tenets of aggregate risk 
assessment: (1) that exposures when aggregated are internally 
consistent and realistic; and (2) that appropriate temporal and 
geographic linkages or correlations/associations between exposure 
scenarios are maintained.
    The chlorpyrifos steady-state dietary (food only) assessment 
considers the potential risk from a 21-day exposure duration using a 3-
week rolling average (sliding by day) across the year. For this 
assessment, the same food residue values used in the acute assessment 
were used for the 21-day duration. In the Calendex software, one diary 
for each individual in the WWEIA is selected to be paired with a 
randomly selected set of residue values for each food consumed. The 
steady-state analysis calculated exposures for the sentinel populations 
for infants (less than 1 year old); children (1 to 2 years old); youths 
(6 to 12 years old); and adults (females 13 to 49 years old). The 
assessment of these index lifestages is protective of other population 
subgroups.
2. Exposure From Drinking Water
a. General Approach for Assessing Exposure From Drinking Water
i. Modeling and Monitoring Data
    Monitoring and modeling are both important tools for estimating 
pesticide concentrations in water and can provide different types of 
information. Monitoring data can provide estimates of pesticide 
concentrations in water that are representative of the specific 
agricultural or residential pesticide practices in specific locations, 
under the environmental conditions associated with a sampling design 
(i.e., the locations of sampling, the times of the year samples were 
taken, and the frequency by which samples were collected). Although 
monitoring data can provide a direct measure of the concentration of a 
pesticide in water, it does not always provide a reliable basis for 
estimating spatial and temporal variability in exposures because 
sampling may not occur in areas with any pesticide use, with the 
highest pesticide use, when the pesticides are being used, and/or at an 
appropriate sampling frequency to detect high concentrations of a 
pesticide that occur over the period of a day to several days.
    Because of the limitations in most monitoring studies, EPA's 
standard approach is to use water exposure models as the primary means 
to estimate pesticide exposure levels in drinking water. Modeling is a 
useful tool for characterizing vulnerable sites and can be used to 
estimate upper-end pesticide water concentrations in surface water and 
groundwater. EPA's computer models use detailed information on soil 
properties, crop characteristics, and weather patterns to estimate 
water concentrations in vulnerable locations where the pesticide could 
be used according to its label. (Ref. 31 at 27-28) EPA's models 
calculate estimated water concentrations of pesticides using laboratory 
data that describe how fast the pesticide breaks down to other 
chemicals and how it moves in the environment at these vulnerable 
locations. Depending on the modeling algorithm (e.g., surface water 
modeling scenarios), daily concentrations can be estimated continuously 
over long periods of time, and for places that are of most interest for 
any particular pesticide.
    EPA relies on models it has developed for estimating pesticide 
concentrations in both surface water and ground water. The most common 
model used to conduct drinking water assessments is the Pesticide in 
Water Calculator (PWC). PWC couples the Pesticide Root Zone Model 
(PRZM) and Variable Volume Water Model (VVWM) together to simulate 
pesticide fate and transport from the field of application to an 
adjacent reservoir. (Ref. 31 at 27-28). The PWC estimates pesticide 
concentrations for an index reservoir that is modeled for site-specific 
scenarios (i.e., weather and soil data) in different areas of the 
country. A detailed description of the models routinely used for 
exposure assessment is available from the EPA OPP Aquatic Models 
website. See EPA's aquatic models for estimating pesticide 
concentrations in food, water, non-target organisms, and residential 
and occupational environments. (Ref. 2).
    In modeling potential surface water concentrations, EPA models 
areas of the country that are vulnerable to surface water 
contamination. Consequently, EPA models exposures occurring in small 
highly agricultural watersheds in different growing areas throughout 
the country, over a 30-year period. The scenarios are designed to 
capture residue levels in drinking water from reservoirs with small 
watersheds with a large percentage of land use in agricultural 
production. EPA believes these assessments are likely reflective of a 
small subset of watersheds across the country and represent a drinking 
water source generally considered to be the most vulnerable to frequent 
high concentrations of pesticides.
    When monitoring data meet certain data quantity criteria, EPA has 
tools available to quantify the uncertainty in available monitoring 
data such that it can be used quantitively to estimate pesticide 
concentrations in drinking water. (Ref. 32) Furthermore, monitoring 
data can be used in a weight of evidence approach with model estimated 
concentrations to increase confidence in the conclusions of a drinking 
water assessment.
ii. Drinking Water Level of Comparison (DWLOC)
    The drinking water level of comparison (DWLOC) is a benchmark that 
can be used to guide refinements of the DWA. For a drinking water 
assessment that utilizes a DWLOC, the calculated DWLOC is compared to 
the EDWC. When the EDWC is greater than the DWLOC, there may be a risk 
concern. Conversely, when the EDWC is less than the DWLOC, there are no 
risks of concern.
    The DWLOC relates to the concept of the ``risk cup,'' which EPA 
developed to facilitate risk refinement when considering aggregate 
human health risk to a pesticide. (Ref. 33) The risk cup is the total 
exposure allowed for a pesticide considering its toxicity and required 
safety factors. The risk cup represents the maximum safe exposure for 
the duration and population being considered. Exposures exceeding the 
risk cup are of potential concern. There are risk cups for each 
pertinent duration of exposure (e.g., acute, short-term, chronic). For 
chlorpyrifos, EPA is using exposure durations of acute (single day, 24 
hours) and steady state (21-day). (Ref. 32).
    In practice, EPA calculates the total exposure from food 
consumption and residential (or other non-occupational) exposures and 
subtracts this value from the maximum safe exposure level. The 
resulting value is the allowable remaining exposure that can come from 
drinking water without the potential for adverse health effects. 
Knowing this allowable remaining exposure and the water consumption for 
each population

[[Page 99197]]

subgroup (e.g., infants), the Agency can calculate the DWLOC, which is 
the estimate of safe concentration of pesticides in drinking water. 
Using this process of DWLOC calculation allows EPA to determine a 
target maximum safe drinking water concentration, thereby identifying 
instances where drinking water estimates require refinement or 
estimates that may be indicative of risk. (Ref. 31 at 19-20).
iii. Scale of Drinking Water Assessment
    Although food is distributed nationally and pesticide residue 
values on food are therefore not expected to vary substantially 
throughout the country, drinking water is locally derived and 
concentrations of pesticides in source water fluctuate over time and 
location for a variety of reasons. Pesticide residues in water 
fluctuate daily, seasonally, and yearly because of the timing of the 
pesticide application, the vulnerability of the water supply to 
pesticide loading through runoff, spray drift and/or leaching, and 
changes in the weather. Concentrations are also affected by the method 
of application, the location, and characteristics of the sites where a 
pesticide is used, the climate, and the type and degree of pest 
pressure, which influences the application timing, rate used, and 
number of treatments in a crop production cycle.
    EPA may conduct a DWA for a national scale depending on the 
pesticide use under evaluation. A national scale DWA may use a single 
upper-end pesticide concentration as a starting point for assessing 
whether additional refinements are needed or estimated pesticide 
concentrations for certain site-specific scenarios that are associated 
with locations in the United States vulnerable to pesticide 
contamination based on pesticide use patterns. (Ref. 31 at 22).
    EPA may also conduct a regional scale DWA to focus on areas where 
pesticide concentrations may be higher than the DWLOC. Under this 
assessment, EPA estimates pesticide concentrations across different 
regions in the United States that are subdivided into different areas 
called hydrologic units, identified by a two-digit hydrologic unit code 
(HUC 2) number. There are 21 HUC 2 regions in the United States, with 
18 of them within the contiguous United States. These areas contain 
either the drainage area of a major river or a combined drainage of a 
series of rivers. See United States Geological Survey (USGS) Water 
Resources of the United States. (Ref. 34) Estimated pesticide 
concentrations under this approach would be associated with a 
vulnerable pesticide use area somewhere within the evaluated region. 
(Ref. 31 at 23).
iv. Drinking Water Refinements
    EPA has defined four assessment tiers for drinking water 
assessments. Lower-tiered assessments are more conservative based on 
the defaults or upper bound assumptions and may compound conservatisms, 
while higher tiers integrate more available data and provide more 
realistic estimates of environmental pesticide concentrations.
    These four tiers vary in the level of resources, the amount of data 
considered, the spatial scale, and the refinement in the estimated 
pesticide concentration. Tier 1 requires the least amount of resources 
and the least amount of data, whereas Tier 4 is resource intensive, 
considers a wide range of sources and types of data, and is spatially 
explicit, resulting in high confidence in the reported pesticide 
concentration. Each successive tier integrates more focused pesticide, 
spatial, temporal, agronomic, and crop-specific information. The order 
in which refinements are considered (i.e., the order in which the 
assessment is refined) is pesticide-specific and depends on the nature 
and quality of the available data used to support the refinement. 
Additional information on the conduct of drinking water assessments can 
be found in the ``Framework for Conducting Pesticide Drinking Water 
Assessment for Surface Water'' (USEPA, 2020) (``DWA Framework 
document''). (Ref. 31).
    As discussed in the DWA Framework document, EPA can incorporate 
several refinements in higher tiered modeling. Two such refinements are 
the percent cropped area (PCA) and the PCT. These are described in the 
document titled ``Integrating a Distributional Approach to Using 
Percent Crop Area (PCA) and Percent Crop Treated (PCT) into Drinking 
Water Assessment.'' (Ref. 35) The PCA refers to the amount of area in a 
particular community water system that is planted with the crop of 
interest (e.g., the default assumption is that the entire watershed is 
planted with a crop of interest). The PCT refers to the amount of the 
cropped area that is treated with the pesticide of interest (e.g., the 
default is that the entire cropped area is treated with the pesticide 
of interest). With additional use and usage data, EPA can refine 
assumptions about the application rate and PCT for use in modeling to 
generate EDWCs that are appropriate for human health risk assessment 
and more accurately account for the contribution from individual use 
patterns in the estimation of drinking water concentrations.
b. Drinking Water Assessment for Chlorpyrifos
    For the chlorpyrifos drinking water assessment, the metabolite 
chlorpyrifos oxon--which forms during water treatment, e.g., 
chlorination, of source water containing chlorpyrifos and is more toxic 
than chlorpyrifos--was selected as the residue of concern. (Ref. 36 and 
37) The range of conversion from parent to oxon depends upon the type 
of water treatment and other conditions. Based on available information 
regarding the potential effects of certain water treatments (e.g., 
chlorination appears to hasten transformation of chlorpyrifos-to-
chlorpyrifos oxon), EPA assumed that all chlorpyrifos in source water 
is converted to chlorpyrifos oxon upon treatment.
    The Agency used a DWLOC approach for assessing aggregate risk from 
chlorpyrifos. EPA calculated DWLOCs for different age groups for both 
the acute aggregate assessment and the steady-state aggregate 
assessment, taking into consideration the food and residential 
contributions to the risk cup. These numbers were provided as a 
benchmark for evaluating drinking water contributions from uses of 
chlorpyrifos across the United States, and whether such concentrations 
would result in aggregate exposures to chlorpyrifos that exceeded the 
Agency's levels of concern. The lowest acute DWLOC calculated was for 
exposure to chlorpyrifos oxon to infants (<1 year old) at 23 ppb; the 
lowest steady-state DWLOC calculated was also for exposure to 
chlorpyrifos oxon to infants (<1 year old) at 4.0 ppb. (Ref. 12 at 45) 
In other words, EDWCs for infants of chlorpyrifos oxon greater than 23 
ppb from a single exposure or 4.0 ppb for a 21-day average would exceed 
EPA's DWLOC and present a risk that exceeds the Agency's level of 
concern.
    In its 2014 DWA, EPA concluded that there were multiple uses of 
chlorpyrifos that could lead to exposures to chlorpyrifos oxon in 
drinking water that exceed the DWLOC. (Ref. 38) The 2014 DWA provided 
the basis for the Agency's proposal to revoke tolerances in 2015. (Ref. 
39) In 2016, EPA conducted a refined DWA that estimated drinking water 
concentrations based on modeling of all registered uses, as well as all 
available surface water monitoring data. That 2016 DWA considered 
several refinement strategies in a two-step process to derive exposure 
estimates for chlorpyrifos and chlorpyrifos oxon across the country. 
The first step was an assessment of

[[Page 99198]]

potential exposure based on the current maximum label rates at a 
national level. This indicated that the EDWCs could be above the DWLOC.
    Because estimated concentrations at the national level exceeded the 
DWLOC, the Agency conducted a more refined assessment of uses on a 
regional level. (Ref. 36 at 73-86) This more refined analysis derived 
EDWCs using the PWC modeling for maximum labeled rates and 1 pound per 
acre by region for each use. The analysis indicated that approved uses 
of chlorpyrifos in certain vulnerable watersheds in every region of the 
country would result in EDWCs that exceed the DWLOC. For example, table 
25 of EPA's 2016 DWA, which provides the range of estimated 
concentrations of chlorpyrifos in drinking water from uses on golf 
courses and agricultural or production crops, shows EDWCs that exceed 
the DWLOC in vulnerable watersheds in every region in the country. 
While the lower end of some of the ranges provided in that table are 
below the DWLOC, those lower numbers reflect a single use (i.e., single 
crop) and do not reflect potential exposure from other uses where 
applications occur at higher rates, more frequently, or in more 
locations made more vulnerable due to soil type, weather, or agronomic 
practices--all of which were permitted by labeling that was approved at 
that time. The relevant estimated concentration for risk assessment 
purposes was the highest concentration across all uses because it 
reflects concentrations that may occur in vulnerable sources of 
drinking water based on approved use instructions. (Ref. 36 at 73-74).
    In addition, a robust quantitative analysis of the monitoring data 
was conducted resulting in concentrations consistent with model-
estimated concentrations above the DWLOC. (Ref. 36 at 90-121) 
Considering both monitoring data and modeling estimates together 
supported the conclusion that drinking water concentrations in regions 
across the country exceeded the DWLOC. (Ref. 36 at 121-123).
    After the EPA's 2016 DWA showed that the DWLOC exceedances are 
possible from several uses, EPA developed refinement strategies to 
examine those estimated regional/watershed drinking water 
concentrations to pinpoint community drinking water systems where 
exposure to chlorpyrifos oxon as a result of chlorpyrifos applications 
may pose an exposure concern. At that time, it was anticipated that a 
more refined drinking water assessment might allow EPA to better 
identify where at-risk watersheds are located throughout the country to 
support more targeted risk mitigation through the registration review 
process. The refinements better account for variability in the use area 
treated within a watershed that may contribute to a drinking water 
intake (referred to as PCA or percent use area when considering non-
agricultural uses) and incorporate data on the amount of a pesticide 
that is actually applied within a watershed for agricultural and non-
agricultural uses (referred to as PCT). These refinement approaches 
underwent external peer review and were issued for public comment in 
January 2020. (Ref. 39 and 40) In addition, EPA used average 
application rates, average numbers of annual applications for specific 
crops, and estimated typical application timing at the state-level 
based on pesticide usage data derived from a statistically reliable 
private market survey database, publicly available survey data 
collected by the USDA, and state-specific scientific literature from 
crop extension experts. (Ref. 1)
    The refinements were integrated in the 2020 DWA. The updated 
assessment applied the new methods for considering the entire 
distribution of community water systems, PCA adjustment factors, 
integrated state level PCT data, incorporated refined usage and 
application data, and included quantitative use of surface water 
monitoring data in addition to considering state level usage rate and 
data information. In addition, given the 2016 DWA calculation of EDWCs 
exceeding the DWLOC of 4.0 ppb, the Agency decided to focus its 
refinements for the 2020 DWA on a subset of uses in specific regions of 
the United States. The purpose of the focus on this subset of uses was 
to determine if limiting use of chlorpyrifos to only certain food uses 
and regions would yield EDWCs below the DWLOC. The subset of uses 
assessed were selected because they were identified as critical uses by 
the registrant and/or high benefit uses to growers. That subset of 
registered uses included the 11 identified crops in the specific 
geographical areas listed in Unit III, and the assessment of those uses 
assumed application rate and timing/frequency restrictions based on 
available usage data as described in the previous paragraph. The 
results of this analysis indicated that the EDWCs from this limited 
subset of uses are below both the acute and chronic DWLOCs. (Ref. 2 at 
16-17) The 2020 DWA refined estimates did not include chlorpyrifos 
exposures from uses beyond that subset and expressly noted that a 
separate assessment would be needed in order to evaluate whether other 
uses could be added to or substituted for the crops and areas already 
identified and still maintain concentrations below the DWLOC.
3. Residential Exposure to Pesticides
a. General Approach to Assessing Residential Exposures
    Residential assessments examine exposure to pesticides in non-
occupational or residential settings (e.g., homes, parks, schools, 
athletic fields or any other areas frequented by the general public), 
based on registered uses of the pesticide. Exposures to pesticides may 
occur to persons who apply pesticides (which is referred to as 
residential handler exposure) or to persons who enter areas previously 
treated with pesticides (which is referred to as post-application 
exposure). Such exposures may occur through oral, inhalation, or dermal 
routes and may occur over different exposure durations (e.g., short-
term, intermediate-term, long-term), depending on the type of pesticide 
and particular use pattern.
    Residential assessments are conducted through examination of 
significant exposure scenarios (e.g., children playing on treated lawns 
or homeowners spraying their gardens) using a combination of generic 
and pesticide-specific data. EPA has prepared SOPs for conducting 
residential assessments on a wide array of scenarios that are intended 
to address the most common uses by which individuals could be exposed 
to pesticides in a non-occupational environment. (Ref. 22) The SOPs 
identify relevant generic data and construct algorithms for calculating 
exposure amounts using these generic data in combination with 
pesticide-specific information. The generic data generally involve 
survey data on behavior patterns (e.g., activities conducted on turf 
and time spent on these activities) and transfer coefficient data. 
Transfer coefficient data measure the amount of pesticide that 
transfers from the environment to humans from a defined activity (e.g., 
hand contact with a treated surface or plant). Specific information on 
pesticides can include information on residue levels as well as 
information on environmental fate such as degradation data.
    Typically, once EPA assesses potential exposures from all 
applicable exposure scenarios, EPA selects the highest exposure 
scenario for each exposed lifestage to calculate representative risk 
estimates for use in the aggregate exposure assessment.

[[Page 99199]]

Those specific exposure values are then combined with the lifestage 
appropriate exposure values provided for food and drinking water to 
determine whether a safety finding can be made. As described above, 
since EPA used a DWLOC approach for assessing risks for chlorpyrifos, 
EPA combined food exposures covered by all chlorpyrifos tolerances with 
residential exposures to identify the DWLOC and compared the DWLOC to 
EDWCs to determine whether a safety finding could be made. The end 
result is the same since both methods aggregate food, drinking water, 
and residential exposure estimates to determine whether a safety 
finding can be made.
b. Residential Exposure Assessment for Chlorpyrifos
    Most chlorpyrifos products registered for residential treatment 
were voluntarily cancelled or phased out by the registrants between 
1997 and 2001; however, some uses of chlorpyrifos remain that may 
result in non-occupational, non-dietary (i.e., residential) exposures, 
specifically roach bait products, fire ant mound treatments, and uses 
on golf courses. The roach bait product is designed such that the 
active ingredient is contained within a bait station, which eliminates 
the potential for contact with the chlorpyrifos containing bait 
material; therefore, residential exposures from the roach bait product 
were determined to be negligible. Since the ant mound treatments can 
only be applied professionally and direct exposure with treated mounds 
is not anticipated, residential exposures from the ant mound use were 
also determined to be negligible. (Ref. 12 at 36-44).
    For the golf course use, the Agency does not anticipate residential 
handler exposures, although there is a potential for residential post-
application exposures that would aggregate with dietary exposures from 
the registered use on golf courses. Based on the anticipated use 
patterns reviewed under the SOP, EPA assessed these exposures as 
steady-state residential post-application exposures, which would be 
protective of shorter durations of exposure. There is a potential for 
dermal post-application exposures from the golf course uses for adults 
(females 13 to 49 years old); youths (11 to less than 16 years old); 
and children (6 to less than 11 years old). Although EPA did not 
identify any post-application risks of concern from use on golf 
courses, EPA used the post-application exposures and risk estimates 
resulting from the golfing scenarios in EPA's aggregate exposure and 
risk assessment.
4. Cumulative Risk
    FFDCA section 408(b)(2)(D)(v), 21 U.S.C. 346a(b)(2)(D)(v), requires 
EPA to consider ``available information concerning the cumulative 
effects of [pesticide chemical] residues and other substances that have 
a common mechanism of toxicity.''
    Chlorpyrifos belongs to a class of pesticides called 
organophosphates (OPs), which share the ability to inhibit AChE through 
phosphorylation of the serine residue on the enzyme leading to 
accumulation of acetylcholine and ultimately cholinergic neurotoxicity. 
This shared mode of action/adverse outcome pathway (MOA/AOP) is the 
basis for the OP common mechanism grouping per OPP's Guidance for 
Identifying Pesticide Chemicals and Other Substances that have a Common 
Mechanism of Toxicity (USEPA, 1999). The 2006 cumulative risk 
assessment for organophosphates (2006 OP CRA) used brain AChE 
inhibition in female rats as the source of dose response data for the 
relative potency factors and PODs for each OP, including chlorpyrifos. 
After considering the potential for cumulative risks of concern from 
the OPs, EPA concluded that the tolerances were safe. (Ref. 21).
    After completion of the single-chemical OP assessments for this 
round of registration review, but prior to the issuance of a final 
registration review decision for chlorpyrifos (and the other OPs), EPA 
will determine whether any updates to the 2006 OP CRA on AChE 
inhibition are necessary. In the meantime, no additional uses have been 
approved since that document was completed (i.e., no additional 
exposures), and many uses have been (or are in the process of being) 
cancelled or reduced (e.g., the current reduction of chlorpyrifos 
uses). As such, EPA expects the potential for cumulative risks and any 
cumulative risk estimates will likely be lower than assessed in 2006, 
when EPA concluded that the results of the cumulative assessment 
support a reasonable certainty of no harm finding as required by FQPA.

C. Aggregate Risk Assessment and Determination of Safety for 
Chlorpyrifos

    The final step in the risk assessment is the aggregate exposure 
assessment and risk characterization. In this step, EPA combines 
information from the first three steps (hazard identification, level of 
concern (LOC)/dose-response analysis, and human exposure assessment) to 
quantitatively estimate the risks posed by a pesticide. The aggregated 
exposure assessment process considers exposure through multiple 
pathways or routes of exposure (e.g., food, water, and residential) for 
different sub-populations (e.g., infants, children ages 1-2) and 
exposure duration or types of effects (e.g., acute (single dose) 
noncancer effects, chronic noncancer effects, and cancer). The 
aggregated exposure assessments can be deterministic (levels of 
exposure for each pathway are point estimates), probabilistic (levels 
of exposure are a distribution for a given population), or a 
combination of the two and are dependent on the level of refinement or 
assessment tier.
    As noted above, EPA evaluates aggregate exposure by comparing 
combined exposure from all relevant sources to the safe level. Where 
exposures exceed the safe level (i.e., the risk cup), they present 
potential risks of concern. There are risk cups for each pertinent 
duration of exposure for a pesticide because the amount of exposure 
that can be incurred without adverse health effects will vary by 
duration (e.g., acute, short-term, chronic).
    Whether risks will exceed the risk cup (i.e., whether exposures are 
expected to exceed safe levels) is expressed differently, depending on 
the type of level of concern the Agency has identified. For dietary 
assessments, the risk is expressed as a percentage of the acceptable 
dose (i.e., the dose which EPA has concluded will be ``safe''). Dietary 
exposures greater than 100% of the acceptable dose are generally cause 
for concern and would be considered ``unsafe'' within the meaning of 
FFDCA section 408(b)(2)(B). For non-dietary (and combined dietary and 
non-dietary) risk assessments of threshold effects, the toxicological 
level of concern is typically not expressed as an RfD/PAD, but rather 
in terms of an acceptable (or target) Margin of Exposure (MOE) between 
human exposure and the PoD. The ``margin'' that is being referred to in 
the term MOE is the ratio between the PoD and human exposure, which is 
calculated by dividing human exposure into the PoD. An acceptable MOE 
is generally considered to be a margin at least as high as the product 
of all applicable safety factors for a pesticide. For example, when the 
Agency retains the default uncertainty factors for dietary or aggregate 
risk (a 10X interspecies uncertainty factor, a 10X intraspecies 
uncertainty factor, and a 10X FQPA safety factor), the total 
uncertainty factor (or level of concern) is 1,000, and any MOE above 
1,000 represents exposures that are not of concern. Like RfD/PADs, 
specific target MOEs are selected for exposures of different durations 
and routes. For non-

[[Page 99200]]

dietary exposures, EPA typically examines short-term, intermediate-
term, and long-term exposures. Additionally, target MOEs may be 
selected based on both the duration of exposure and the various routes 
of non-dietary exposure--dermal, inhalation, and oral. Target MOEs for 
a given pesticide can vary depending on the characteristics of the 
studies relied upon in choosing the PoD for the various duration and 
route scenarios.
    In addition, in a DWLOC aggregate risk assessment, the calculated 
DWLOC is compared to the EDWC. Where EPA has calculated a DWLOC, it can 
determine whether drinking water exposures will result in aggregate 
risks of concern by comparing estimated pesticide concentrations in 
drinking water to the DWLOC. As noted above, an aggregate DWLOC 
represents the amount of allowable safe residues of pesticide in 
drinking water because it represents the room remaining in the risk cup 
after accounting for the food and residential exposures. The DWLOC 
provides an estimate of the allowable safe concentrations of pesticides 
in drinking water for comparison to EDWCs. When the EDWC is less than 
the DWLOC, there are no risk concerns for aggregate exposures because 
the Agency can conclude that the contribution from drinking water when 
aggregated with food and residential/non-occupational exposures will 
not exceed save levels of exposure. Conversely, an EDWC at or exceeding 
the DWLOC would indicate a risk of concern, as those exposures to 
chlorpyrifos in drinking water, when aggregated with exposures from 
food and residential exposures, would exceed safe levels of exposure. 
(Ref. 41).
1. Dietary Risks From Food Exposures
    As noted above, EPA's acute and steady-state dietary (food only) 
exposure assessments for chlorpyrifos were highly refined and 
incorporated monitoring data for almost all foods. The Agency assessed 
food exposures based on all food uses of chlorpyrifos for which 
tolerances have been established, including all uses registered at the 
time of the 2020 HH DRA. It did not include potential exposure from 
food handling establishment uses since the Agency did not identify any 
actual usage under the registered food handling establishment uses. 
Previous assessments of the food handling establishment uses had 
indicated negligible residues. (Ref. 12 at 33-36 and 31 at 3).
    Considering food exposures alone, the Agency did not identify risks 
of concern for either acute or steady-state exposures. (Ref. 12 at 34-
36) Acute dietary (food only) risk estimates, which are based on risk 
from a single exposure event in the 2020 HH DRA, were all below 100% of 
the acute population adjusted dose for food (aPADfood) at 
the 99.9th percentile of exposure and are not of concern. The 
population with the highest risk estimate was females (13 to 49 years 
old) at 3.2% aPADfood. Steady-state dietary (food only) risk 
estimates, which are based on the potential risk from a 21-day exposure 
duration using a 3-week rolling average (sliding by day) across the 
year, were also all below 100% of the steady-state PAD for food 
(ssPADfood) at the 99.9th percentile of exposure and are not 
of concern. The population with the highest risk estimate was children 
(1 to 2 years old) at 9.7% ssPADfood. Note: Because the 
Agency has retained the 10X FQPA SF, as indicated in Unit VI.C.3., the 
relevant risk estimates are those associated with the retention of the 
10X FQPA SF. The risk estimates associated with a 1X FQPA SF were 
provided solely to identify a range of risk estimates to characterize 
the risk in the event that EPA identified reliable data to support 
another FQPA SF that would be safe for infants and children, but no 
such data has been identified.
    Following the approval of the product and use cancellation 
requests, the Agency has not conducted a separate quantitative 
assessment of the anticipated risk from food exposures from the 11 food 
uses remaining. Given that the cancellation actions will reduce 
exposure from residues in food and the current assessment with all 
currently registered food uses indicates there is no risk of concern 
from exposure to residues on all food for which there are tolerances, 
the Agency concludes that there will still be no risks of concern from 
exposure to residues of chlorpyrifos on food after most of the food 
uses are cancelled.
2. Non-Occupational, Non-Dietary (Residential) Risks
    Because there are some uses of chlorpyrifos that may result in 
residential exposures, EPA assessed risk from those uses. All 
residential post-application risk estimates for the registered uses of 
chlorpyrifos were below the Agency's level of concern. (Ref. 12 at 38) 
The residential post-application LOC for children is 40, and the lowest 
risk estimate for children (11 to less than 16 years old) was 1,200. 
The residential post-application LOC for adults is 100, and the lowest 
risk estimate is 1,000. Because the calculated MOEs are above the 
Agency's level of concern, there are no risks of concern from 
residential exposures.
3. Risks From Drinking Water
    As noted above, the Agency aggregated exposures to chlorpyrifos 
from food and residential exposures and calculated the DWLOC, i.e., the 
amount of drinking water exposures that would be considered safe, based 
on how much room was left in the risk cup after accounting for food and 
residential/non-occupational exposures. The Agency calculated acute and 
steady-state DWLOCs for infants (less than 1 year old); children (1 to 
2 years old); youths (6 to 12 years old), and adults (females 13 to 49 
years old), which would be protective of other subpopulations. The most 
sensitive acute DWLOC was 23 ppb chlorpyrifos oxon, and the most 
sensitive steady-state DWLOC was 4.0 ppb chlorpyrifos oxon.
    As indicated above in Unit IV.B.2., the Agency estimated drinking 
water contributions from the 11 food uses identified in Unit III. above 
in its 2020 DWA for both acute and steady-state exposure durations. 
Those estimates were based on limiting those uses to specific states 
and were modeled based on usage data concerning application frequency 
and application rates. These application rate and maximum number of 
application-per-year restrictions vary by use site, as specified in the 
2020 DWA. (Ref. 2) That document indicated that EDWCs for those food 
uses with those specific limitations would be below the acute DWLOC of 
23 ppb and the steady-state DWLOC of 4.0 ppb. The underlying assumption 
of the 2020 DWA was that there would be no other food uses contributing 
to drinking water exposures. As indicated in Unit III., all 
chlorpyrifos registrants have submitted requests to cancel all other 
food uses and to amend products for use on food consistent with the 
restrictions identified in Unit III; EPA has completed approval of the 
label amendments and expects to finalize the cancellations by the end 
of 2024, prior to the time this rule is finalized. Under the terms of 
those cancellation orders, use of chlorpyrifos will not be permitted on 
food except on the 11 remaining uses in accordance with the new label 
restrictions after June 30, 2025. As a result, EPA anticipates that use 
of chlorpyrifos products with the more restrictive labeling will result 
in drinking water exposures below the DWLOC.
4. Aggregate Exposure and Determination Concerning Safety
    As noted above, in accordance with FFDCA section 408(b)(2), EPA 
must,

[[Page 99201]]

when establishing or leaving in effect tolerances for residues of a 
pesticide chemical, determine that the tolerances are safe. That is, 
EPA must determine that ``there is a reasonable certainty that no harm 
will result from aggregate exposure to the pesticide chemical residue, 
including all anticipated dietary exposures and all other exposures for 
which there is reliable information.'' (21 U.S.C. 346a(b)(2)).
    As discussed earlier in this Unit, exposures from food and 
residential/non-occupational exposures, taken separately or together, 
do not exceed EPA's levels of concern. The Agency determined that risks 
from exposures to chlorpyrifos residues in food (from all food uses 
registered at the time of the 2020 HHRA) comprised 3.2% of the aPAD for 
females (13 to 49 years old) and 9.7% of the ssPAD for children (1 to 2 
years old), the highest exposed subpopulations. Combining those 
exposures with relevant residential exposures, which did not exceed the 
Agency's levels of concern, the Agency calculated the levels of 
drinking water concentrations that would be safe, i.e., the DWLOCs. The 
lowest DWLOC for acute exposures (for infants) is 23 ppb, and the 
lowest DWLOC for steady-state exposures (for infants) is 4.0 ppb; 
therefore, any EDWCs of chlorpyrifos oxon exceeding 23 ppb in an acute 
scenario or 4.0 ppb in a steady-state exposure scenario indicate that 
aggregate exposures of chlorpyrifos would be unsafe.
    The Agency's 2020 DWA demonstrates that the DWLOCs will not be 
exceeded for the 11 uses as assessed in that document, i.e., where 
those uses are limited to specific geographic areas and with 
restrictions on application rates and frequency. Those restrictions are 
described in Unit III. Because the registrants have, under FIFRA, 
requested cancellation of all other food uses and have submitted label 
amendments that reflect the necessary restrictions on the remaining 
food uses for consistency with the assumptions in the 2020 DWA, EPA 
considers the more limited exposure to be reasonably anticipated at 
this time, unlike at the time of the 2021 Final Rule when no such 
requests had been submitted. Use consistent with the amended labels 
will result in drinking water exposures that are below the DWLOC, and 
consequently, there is a reasonable certainty that no harm will result 
from aggregate exposure (including food, drinking water, and 
residential/non-occupational exposures) to chlorpyrifos. Therefore, EPA 
concludes that the tolerances remaining in place will be safe.

V. Petition Response

    As noted in Unit II.D., PANNA and NRDC submitted a petition to EPA 
in September 2007, seeking revocation of all chlorpyrifos tolerances 
and cancellation of all chlorpyrifos registrations (``2007 Petition''). 
The 2007 Petition raised the following claims in support of that 
request:
    1. EPA has ignored genetic evidence of vulnerable populations.
    2. EPA has needlessly delayed a decision regarding endocrine 
disrupting effects.
    3. EPA has ignored data regarding cancer risks.
    4. EPA's 2006 OP CRA misrepresented risks and failed to apply the 
10X FQPA Safety Factor.
    5. EPA has over-relied on registrant data.
    6. EPA has failed to properly address the exporting hazard in 
foreign countries from chlorpyrifos.
    7. EPA has failed to quantitatively incorporate data demonstrating 
long-lasting effects from early life exposure to chlorpyrifos in 
children.
    8. EPA has disregarded data demonstrating that there is no evidence 
of a safe level of exposure during pre-birth and early life stages.
    9. EPA has failed to cite or quantitatively incorporate studies and 
clinical reports suggesting potential adverse effects below 10% 
cholinesterase inhibition.
    10. EPA has failed to incorporate inhalation routes of exposure.
    In a response dated July 16, 2012, EPA explained that all but one 
of the issues raised in the 2007 Petition relate to EPA's establishment 
of the chlorpyrifos tolerances under the FFDCA that would be addressed 
in either a rule or an order issued under the FFDCA. (Ref. 42) The one 
issue that was not related to the safety of the tolerances was claim 6, 
which EPA denied in that July 16, 2012, response. EPA expressly noted 
that its denial of claim 6 was a final agency action subject to 
judicial review under section 16 of FIFRA; that denial was never 
challenged.
    The only claims remaining in the 2007 Petition, therefore, are 
claims related to the safety of the chlorpyrifos tolerances that must 
be addressed under the FFDCA. Because of the integration of the safety 
standard into the FIFRA registration standard, if EPA were to determine 
that the tolerances were unsafe, then the corresponding food uses would 
not meet the FIFRA standard for registration and must be cancelled. If, 
however, EPA were to determine that the 2007 Petition does not provide 
a basis for determining that the tolerances associated with the 11 
remaining food uses are unsafe, as EPA is proposing to do in this 
document, there would be no separate basis in the 2007 Petition for a 
cancellation action under FIFRA. Section 408(h)(5) prohibits the review 
of issues under other statutes, for which review is obtainable under 
the FFDCA. 21 U.S.C. 346a(h)(5). Accordingly, EPA intended, as 
indicated in its July 2012 response, and intends currently to treat the 
final rule of this rulemaking as its final response to the remaining 
claims in the 2007 Petition.
    Regarding the remaining claims, which must be reviewed under the 
FFDCA, EPA denied the rest of the claims in the 2017 Denial Order and 
denied the objections to that order in the 2019 Denial Order. (Ref. 10 
and 43) After the 2017 and 2019 Denial Orders were vacated by the Ninth 
Circuit in 2021, EPA granted the 2007 Petition as part of the 2021 
Final Rule, as directed by the Ninth Circuit, but that 2021 Final Rule 
(and petition response) was subsequently vacated by the Eighth Circuit 
in 2023.
    As noted above, however, EPA is taking action in this rulemaking to 
revoke most tolerances, which is consistent, in part, with the 2007 
Petition's request. Based on the available data, use of chlorpyrifos 
has been decreasing (also noted in section IV.B.4 of this rule). 
Cancelling all food uses but the 11 mentioned in Unit III. above--along 
with geographic limitations and additional application restrictions--
will contribute to the decrease of chlorpyrifos applied in the United 
States compared to historical usage. In addition, to address concerns 
about whether the rest of the tolerances should be revoked as requested 
by the 2007 Petition, EPA has provided a safety determination in Unit 
IV. above. To the extent the Petition's request to revoke tolerances is 
not fully addressed above, EPA is clarifying its responses to the 
specific claims in this Unit.
    EPA provided responses to the specific claims 1-5 and 10 in the 
2017 Denial Order. EPA's position on those issues has not changed, and 
thus EPA is incorporating those responses into this document by 
reference. Those responses can be found in Unit V.1-5 and 10 of the 
2017 Petition Denial. See 82 FR at 16585-91.
    EPA has grouped claims 7-9 together because they fundamentally all 
raise the same issue: Whether the potential exists for chlorpyrifos to 
cause neurodevelopmental effects in infants and children from exposures 
(either to mothers during pregnancy or directly to

[[Page 99202]]

infants and children) that are lower than those resulting in 10% 
cholinesterase inhibition--the basis for EPA's long-standing point of 
departure in regulating chlorpyrifos and other OPs.
    The petitioners assert that human epidemiology and rodent 
developmental neurotoxicity data suggest that pre-natal and early life 
exposure to chlorpyrifos can result in long-lasting, possibly permanent 
damage to the nervous system and that these effects are likely 
occurring at exposure levels below 10% cholinesterase inhibition, EPA's 
existing regulatory standard for chlorpyrifos and other OPs. They 
assert that EPA has therefore used the wrong endpoint as a basis for 
regulation and that, taking into account the full spectrum of toxicity, 
chlorpyrifos does not meet the FFDCA safety standard (and thus does not 
meet the FIFRA standard for registration, which integrates the FFDCA 
safety standard).
    EPA initiated a science evaluation of the potential effects on 
neurodevelopment in 2007 following the receipt of the 2007 Petition. 
EPA has three times presented approaches and proposals to the FIFRA SAP 
for evaluating epidemiologic, laboratory animal, and mechanistic data 
exploring the possible connection between in utero and early childhood 
exposure to chlorpyrifos and adverse neurodevelopmental effects. The 
FIFRA SAP reports have rendered numerous recommendations for additional 
study and sometimes conflicting advice for how EPA should consider (or 
not consider) the epidemiology data in conducting EPA's registration 
review human health risk assessment for chlorpyrifos. For over two 
decades, EPA has evaluated the scientific evidence surrounding the 
different health effects associated with chlorpyrifos. The Agency's 
position on the strengths and weaknesses of the available 
epidemiological, laboratory animal, and mechanistic data as laid out in 
the 2020 HH DRA is discussed in Unit IV.A.2.b above.
    As noted in that section and in Unit IV.A.3., EPA concludes that 
the available epidemiological data does not provide a sufficient basis 
for calculating a PoD nor does it support a conclusion that PoDs based 
on the 10% AChE inhibition are not protective. Nevertheless, as 
discussed in Unit IV.A.3.c., EPA has retained the 10X FQPA SF to 
account for the uncertainties around the dose-response level for 
neurodevelopmental effects for the purpose of this rule.
    Through this proposal, EPA is proposing to take action to revoke 
most chlorpyrifos tolerances as requested in the 2007 Petition but is 
not proposing to revoke tolerances associated with the remaining 
registered uses because the Agency's analysis in the 2020 HH DRA and 
the 2020 DWA support a conclusion that those tolerances are safe. The 
voluntary cancellations will effectuate a reduction in exposures, and 
because exposures will be reduced, the underlying assessment, even with 
the retention of the default 10X FQPA SF, supports the retention of the 
remaining tolerances.
    EPA is proposing that the claims in the 2007 Petition do not 
provide a basis for concluding that the tolerances not being revoked 
are unsafe.

VI. Request for Public Comment

    The Agency is requesting comments on this proposal.
    During the lengthy pendency of the 2007 Petition to revoke 
tolerances and the registration review process for chlorpyrifos, the 
public has had numerous opportunities to comment on EPA's scientific 
conclusions, risk assessments, regulatory proposals, and rules. 
Hundreds of thousands of comments have been submitted, and those 
comments have informed EPA's subsequent assessments and regulatory 
decision making.
    As this is a proposed rule, EPA is providing an opportunity to 
comment on issues related to this proposal, and EPA will consider 
significant comments in the final rule. Comments on this particular 
proposal must be submitted at this time, even if that person has 
submitted comments at other times during the history of chlorpyrifos 
regulatory actions.

VII. Other Administrative Considerations

A. Tolerance Expiration Date

    EPA is proposing to set an expiration date for the chlorpyrifos 
tolerances being revoked so that those tolerances will expire on July 
1, 2025. This date would align with the existing stocks provisions for 
the related cancellation actions, which allow use of existing stocks of 
some cancelled chlorpyrifos products on food until June 30, 2025. This 
approach is also intended to satisfy the U.S. commitments under the SPS 
Agreement, requiring Members to provide a ``reasonable interval'' 
between the publication of a regulation subject to the Agreement and 
its entry into force to allow time for producers in exporting Member 
countries to adapt to the new requirement.
    Any commodities treated with chlorpyrifos that are in the channels 
of trade and impacted by the tolerance revocations shall be subject to 
FFDCA section 408(1)(5). That section provides that any residues of the 
subject pesticide in or on such food shall not render the food 
adulterated so long as it is shown to the satisfaction of the Food and 
Drug Administration that:
    1. The residue is present as the result of an application or use of 
the pesticide at a time and in a manner that was lawful under FIFRA, 
and
    2. The residue does not exceed the level that was authorized at the 
time of the application or use to be present on the food under a 
tolerance or exemption from tolerance. Evidence to show that food was 
lawfully treated may include records that verify the dates when the 
pesticide was applied to such food.
    The tolerance revocations in this proposed rule are not 
discriminatory and are designed to ensure that both domestically 
produced and imported foods meet the food safety standard established 
by the FFDCA. The same food safety standards apply to domestically 
produced and imported foods.

B. Severability

    This proposed rule includes two distinct actions concerning 
chlorpyrifos tolerances. Specifically, the Agency is proposing: (1) to 
revoke all tolerances associated with use cancellations as those 
tolerances are no longer needed and (2) that the tolerances not being 
revoked are safe. The Agency intends that these two actions be 
severable from each other, although for purposes of expediency and to 
fully address the pending 2007 Petition, EPA is proposing to include 
all parts in one rulemaking. (21 U.S.C. 346a(l)(1)). However, EPA 
retains the discretion to take each of these actions separately, with 
each implementing a portion or portions of this proposed rule.
    The revocation of tolerances that are no longer needed is an almost 
entirely ministerial action. Because those uses of chlorpyrifos on 
these commodities will no longer be registered in the United States, 
the corresponding tolerances are considered unnecessary. The Agency's 
typical process is to automatically remove tolerances from the 
regulations that are no longer necessary. The only element of agency 
discretion involved in revocation of most tolerances would arise from a 
hypothetical request that EPA retain certain tolerances for purposes of 
importing food treated with chlorpyrifos. The proposal to revoke all 
tolerances except for those on the 11 specified crops depends neither 
on the Agency making a safety finding for the remaining tolerances nor 
on the Agency's response to the 2007 Petition.

[[Page 99203]]

Even if safety of the tolerances not being revoked is challenged, the 
revocation of unnecessary tolerances would not be affected and would 
stand on its own right; EPA could re-evaluate the safety of the 
remaining tolerances and either provide additional justification for 
its safety determination or take other action--if needed--to address 
the safety of chlorpyrifos tolerances. The tolerances proposed for 
revocation in this document would remain revoked in such circumstances.
    This discussion of separate actions proposed in this document is 
not intended to be exhaustive and should not be viewed as an intention 
by EPA to consider other actions or determinations proposed herein as 
non-severable from other parts of the proposed rule.

VIII. Statutory and Executive Order Reviews

    In this proposed rule, EPA is proposing to revoke specific 
tolerances established under FFDCA section 408. The Office of 
Management and Budget (OMB) has exempted this type of action (e.g., 
tolerance revocation for which extraordinary circumstances do not 
exist) from review under Executive Order 12866, entitled ``Regulatory 
Planning and Review'' (58 FR 51735, October 4, 1993). These revocations 
are not expected to present extraordinary circumstances because the 
registrants have requested to voluntarily cancel uses associated with 
these tolerances, which means that the tolerances will no longer be 
needed to cover residues of chlorpyrifos in or on those food 
commodities. Because this proposed rule has been exempted from review 
under Executive Order 12866, this proposed rule is not subject to 
Executive Order 13211, entitled ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 
28355, May 22, 2001).
    This proposed rule does not contain any information collections 
subject to OMB approval under the Paperwork Reduction Act (PRA) (44 
U.S.C. 3501 et seq.) or impose any enforceable duty or contain any 
unfunded mandate as described under Title II of the Unfunded Mandates 
Reform Act (UMRA) (2 U.S.C. 1501 et seq.). Nor does it require any 
special considerations as required by Executive Order 12898, entitled 
``Federal Actions to Address Environmental Justice in Minority 
Populations and Low-Income Populations'' (59 FR 7629, February 16, 
1994); or OMB review or any other Agency action under Executive Order 
13045, entitled ``Protection of Children from Environmental Health 
Risks and Safety Risks'' (62 FR 19885, April 23, 1997). However, EPA 
considered the best available science in order to protect children 
against environmental health risks and this proposed rule is consistent 
with EPA's 2021 Policy on Children's Health (Oct. 5, 2021). (Ref. 43).
    This proposed rule does not involve any technical standards that 
would require Agency consideration of voluntary consensus standards 
pursuant to section 12(d) of the National Technology Transfer and 
Advancement Act (NTTAA) (15 U.S.C. 272 note). In addition, the Agency 
has determined that this proposed rule will not have a substantial 
direct effect on States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government, as specified 
in Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999). This proposed rule directly regulates growers, food 
processors, food handlers, and food retailers, not states, including a 
state's ability to register pesticide products. This proposed rule does 
not alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of FFDCA section 408(n)(4). For these same reasons, the Agency has 
determined that this proposed rule does not have any ``tribal 
implications'' as described in Executive Order 13175, entitled 
``Consultation and Coordination with Indian Tribal Governments'' (65 FR 
67249, November 9, 2000).
    In addition, pursuant to section 605(b) of the Regulatory 
Flexibility Act (RFA) (5 U.S.C. 601 et seq.), the Agency hereby 
certifies that the revocation of these tolerances in response to the 
cancellation of associated food uses will not have a significant impact 
on a substantial number of small entities. The certification presented 
above is based on the following rationale. In the case of domestically 
grown food, the tolerance revocations contained in this notice, as is 
generally the case, will have no economic impact. The associated 
pesticide registered uses are in the process of being canceled at this 
time, as requested by the registrants. By the time this rule is 
finalized, EPA intends to have approved all requested cancellations, 
and use will only be permitted on food consistent with the existing 
stocks provisions of those orders. Pursuant to the cancellation orders, 
U.S. growers will be prohibited from using chlorpyrifos on the foods 
for which this rule proposes revoking tolerances after June 30, 2025. 
Accordingly, revoking the tolerances themselves will have no effect on 
food grown in the United States. As for food grown in the United 
States, it will not be considered adulterated if it was treated in a 
way that complied with the tolerance in effect at the time of treatment 
and the use is consistent with the applicable cancellation order. The 
revocation of a pesticide tolerance generally has a greater potential 
to affect foreign-grown food, since the uses of the pesticide 
prohibited in the United States may still be lawful in other countries. 
If foreign growers use the pesticide after the tolerances are revoked, 
the food they grow will be considered adulterated and cannot be 
imported.

IX. References

    EPA has established an official record for this rulemaking. The 
official record includes all information considered by EPA in 
developing this proposed rule. This official record includes all 
information physically located in docket ID number EPA-HQ-OPP-2024-
0431, any documents identified in this proposal, and documents 
referenced in documents in the docket. The public version of the 
official record does not include any information claimed as CBI.

1. U.S. EPA (2020). Chlorpyrifos Proposed Interim Registration 
Review Decision. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0971.
2. U.S. EPA (2020). Chlorpyrifos Updated Drinking Water Assessment 
for Registration Review. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0941.
3. U.S. EPA (2022). Cancellation Order for Certain Chlorpyrifos 
Registrations. Available at: https://www.federalregister.gov/documents/2022/08/31/2022-18838/cancellation-order-for-certain-chlorpyrifos-registrations.
4. U.S. EPA (2023). Final Cancellation Order for Certain 
Chlorpyrifos Registrations and Uses. Available at: https://www.federalregister.gov/documents/2023/11/06/2023-24462/final-cancellation-order-for-certain-chlorpyrifos-registrations-and-uses.
5. U.S. EPA (2023). Cancellation Order for Certain Chlorpyrifos 
Registrations and Uses. Available at: https://www.federalregister.gov/documents/2023/05/04/2023-09396/cancellation-order-for-certain-chlorpyrifos-registrations-and-uses.
6. U.S. EPA (2023). Final Cancellation Order for Certain 
Chlorpyrifos Registrations and Uses. Available at: https://www.federalregister.gov/documents/2023/11/06/2023-24462/final-cancellation-order-for-certain-chlorpyrifos-registrations-and-uses.
7. U.S. EPA (2024). Final Cancellation Order for Certain 
Chlorpyrifos Registrations

[[Page 99204]]

and Uses. Available at: https://www.federalregister.gov/documents/2024/06/24/2024-13779/final-cancellation-order-for-cancelling-certain-pesticide-registrations-and-uses.
8. U.S. EPA (2024) Chlorpyrifos; Final Cancellation Order for 
Certain Pesticide Registrations and Amendment of Certain Pesticide 
Registrations to Terminate Certain Uses. Available at: https://www.federalregister.gov/documents/2024/08/07/2024-17453/chlorpyrifos-final-cancellation-order-for-certain-pesticide-registrations-and-amendment-of-certain.
9. U.S. EPA (2016). Chlorpyrifos: Revised Human Health Risk 
Assessment for Registration Review (November 3, 2016). Available at: 
https://www.regulations.gov/document/EPA-HQ-OPP-2015-0653-0454.
10. U.S. EPA (2017) Chlorpyrifos; Order Denying PANNA and NRDC's 
Petition to Revoke Tolerances. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2007-1005-0100.
11. U.S. EPA (2023) Pesticide Tolerance; Exemptions, Petitions, 
Revocations, etc.: Implementing Registration Review Decisions for 
Certain Pesticides; Aluminum tris (O-ethylphosphonate), Carbon 
disulfide, et al. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2017-0128-0005.
12. U.S. EPA (2020) Chlorpyrifos: Third Revised Human Health Risk 
Assessment for Registration Review. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0944.
13. A User's Guide to Available EPA Information on Assessing 
Exposure to Pesticides in Food (June 21, 2000). Available at: 
https://www.doh.wa.gov/Portals/1/Documents/4000/PASW_exposurefood.pdf.
14. U.S. EPA (2002) Determination of the Appropriate FQPA Safety 
Factor(s) in Tolerance Assessment. Available at: https://www.epa.gov/sites/default/files/2015-07/documents/determ.pdf.
15. U.S. EPA (2000). Chlorpyrifos Human Health Risk Assessment. 
Available at: https://archive.epa.gov/scipoly/sap/meetings/web/pdf/hed_ra.pdf.
16. U.S. EPA (2011). Chlorpyrifos: Preliminary Human Health Risk 
Assessment for Registration Review. Available in docket number EPA-
HQ-OPP-2008-0850, https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0025.
17. U.S. EPA (2016). Scientific Advisory Panel for Chlorpyrifos: 
Analysis of Biomonitoring Data. Available at: https://www.epa.gov/sites/default/files/2016-07/documents/chlorpyrifos_sap_april_2016_final_minutes.pdf.
18. U.S. EPA (2016). Summary Reviews for Additional Epidemiological 
Literature Studies from Prospective Birth Cohort Studies. Available 
in docket number EPA-HQ-OPP-2015-0653 at https://www.regulations.gov/document/EPA-HQ-OPP-2015-0653-0438.
19. U.S. EPA (2020). The Use of New Approach Methodologies (NAMs) to 
Derive Extrapolation Factors and Evaluate Developmental 
Neurotoxicity for Human Health Risk Assessment. Available in docket 
number EPA-HQ-OPP-2020-0263 at https://www.regulations.gov/document/EPA-HQ-OPP-2020-0263-0033.
20. FIFRA Scientific Advisory Panel (2012). ``Scientific Issues 
Associated with Chlorpyrifos''. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2012-0040-0029.
21. U.S. EPA (2006). Revised Organophosphorous Pesticide Cumulative 
Risk Assessment. Available at https://downloads.regulations.gov/EPA-HQ-OPP-2006-0618-0002/content.pdf.
22. U.S. EPA (2012). Standard Operating Procedures for Residential 
Pesticide Exposure Assessment https://www.epa.gov/sites/default/files/2015-08/documents/usepa-opp-hed_residential_sops_oct2012.pdf.
23. FIFRA Scientific Advisory Panel (2002). ``Organophosphate 
Pesticides: Preliminary OP Cumulative Risk Assessment.'' Information 
on how to obtain the meeting report is available at https://www.epa.gov/sap/fifra-scientific-advisory-panel-meetings.
24. EPA's Exposure Factors Handbook. Available at: https://www.epa.gov/expobox/about-exposure-factors-handbook.
25. U.S. EPA (2014). Guidance for Applying Quantitative Data to 
Develop Data-Derived Extrapolation Factors for Interspecies and 
Intraspecies Extrapolation. Available at: https://www.epa.gov/sites/default/files/2015-01/documents/ddef-final.pdf.
26. U.S. EPA (2014). Chlorpyrifos: Revised Human Health Risk 
Assessment for Registration Review. Available in docket number EPA-
HQ-OPP-2008-0850, https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0195.
27. U.S. EPA (2016). Office of Pesticide Programs' Framework for 
Incorporating Human Epidemiologic & Incident Data in Risk 
Assessments for Pesticides. (2016) Available at: https://www3.epa.gov/pesticides/EPA-HQ-OPP-2008-0316-DRAFT-0075.pdf.
28. A User's Guide to Available EPA Information on Assessing 
Exposure to Pesticides in Food (June 21, 2000). Available at: 
https://www.doh.wa.gov/Portals/1/Documents/4000/PASW_exposurefood.pdf.
29. U.S. EPA (2000). Choosing a Percentile of Acute Dietary Exposure 
as a Threshold of Regulatory Concern. Available at: https://www.epa.gov/sites/production/files/2015-07/documents/trac2b054_0.pdf.
30. U.S. EPA (2014). Chlorpyrifos Acute and Steady Dietary (Food 
Only) Exposure Analysis to Support Registration Review. Available 
at: https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0197.
31. U.S. EPA (2020). Framework for Conducting Pesticide Drinking 
Water Assessments for Surface Water. Environmental Fate and Effects 
Division. Office of Pesticide Programs. Office of Chemical Safety 
and Pollution Prevention. U.S. Environmental Protection Agency. 
Available at: https://www.epa.gov/sites/default/files/2020-09/documents/framework-conducting-pesticide-dw-sw.pdf.
32. FIFRA Scientific Advisory Panel (2019) ``Approaches for 
Quantitative Use of Surface Water Monitoring Data in Pesticide 
Drinking Water Assessments.'' Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2019-0417-0019.
33. U.S. EPA (2001). General Principles for Performing Aggregate 
Exposure and Risk Assessments. Available at: https://www.epa.gov/sites/default/files/2015-07/documents/aggregate.pdf.
34. United States Geological Survey (USGS) Water Resources of the 
United States https://water.usgs.gov/GIS/huc.html.
35. U.S. EPA (2020). Appendix B. Case Study for Integrating a 
Distributional Approach to Using Percent Crop Area (PCA) and Percent 
Crop Treated (PCT) into Drinking Water Assessment. Available at: 
https://www.regulations.gov/document/EPA-HQ-OPP-2020-0279-0002.
36. U.S. EPA (2016). Chlorpyrifos Refined Drinking Water Assessment 
for Registration Review. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2015-0653-0437.
37. U.S. EPA (2014). Chlorpyrifos Updated Drinking Water Assessment 
for Registration Review. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2008-0850-0198.
38. U.S. EPA (2015). Proposed Rule: Tolerance Revocations: 
Chlorpyrifos. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2015-0653-0001.
39. U.S. EPA (2019). Documents on PCA/PCT and New Scenario Methods 
for Estimating Pesticide Concentration in Drinking Water. Available 
at https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/documents-pcapct-and-new-scenario-methods.
40. U.S. EPA (2020). Pesticide Drinking Water Assessment 
Improvements. Available at https://www.regulations.gov/docket/EPA-HQ-OPP-2020-0279/document.
41. U.S. EPA (2011). Finalization of Guidance on Incorporation of 
Water Treatment Effects on Pesticide Removal and Transformations in 
Drinking Water Exposure Assessments. Available at: https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/finalization-guidance-incorporation-water-treatment.
42. U.S. EPA (2012) EPA's Partial Response to Chlorpyrifos Petition 
by NRDC & PANNA. Available at: https://www.regulations.gov/document/EPA-HQ-OPP-2007-1005-0095.
43. U.S. EPA (2019) Chlorpyrifos; Final Order Denying Objections to 
March 2017 Petition Denial Order. Available at https://www.regulations.gov/document/EPA-HQ-OPP-2007-1005-0527.

[[Page 99205]]

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests, Reporting and 
recordkeeping requirements.

    Dated: November 27, 2024.
Edward Messina,
Director, Office of Pesticide Programs.

    Therefore, for the reasons stated in the preamble the Environmental 
Protection Agency proposes to amend 40 CFR part 180 as follows:

PART 180--TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES 
IN FOOD

0
1. The authority citation for part 180 continues to read as follows:

    Authority:  21 U.S.C. 321(q), 346a and 371.

0
2. Revise Sec.  180.342 to read as follows:


Sec.  180.342   Chlorpyrifos; tolerances for residues.

    (a) General. (1) Tolerances are established for residues of the 
pesticide chlorpyrifos per se (O,O-diethyl-O-(3,5,6-trichloro-2-
pyridyl) phosphorothioate) in or on the following food commodities:

                       Table 1 to Paragraph (a)(1)
------------------------------------------------------------------------
                                                           Tolerance
            Commodity              Parts per million    expiration date
------------------------------------------------------------------------
Alfalfa, forage.................                 3.0                None
Alfalfa, hay....................                  13                None
Almond..........................                 0.2            7/1/2025
Almond, hulls...................                  12            7/1/2025
Apple...........................                0.01                None
Apple, wet pomace...............                0.02                None
Banana..........................                 0.1            7/1/2025
Beet, sugar, dried pulp.........                 5.0                None
Beet, sugar, molasses...........                  15                None
Beet, sugar, roots..............                 1.0                None
Beet, sugar, tops...............                 8.0                None
Cattle, fat.....................                 0.3                None
Cattle, meat....................                0.05                None
Cattle, meat byproducts.........                0.05                None
Cherry, sweet...................                 1.0            7/1/2025
Cherry, tart....................                 1.0                None
Citrus, dried pulp..............                 5.0                None
Citrus, oil.....................                  20                None
Corn, field, forage.............                 8.0            7/1/2025
Corn, field, grain..............                0.05            7/1/2025
Corn, field, refined oil........                0.25            7/1/2025
Corn, field, stover.............                 8.0            7/1/2025
Corn, sweet, forage.............                 8.0            7/1/2025
Corn, sweet, kernel plus cob                    0.05            7/1/2025
 with husk removed..............
Corn, sweet, stover.............                 8.0            7/1/2025
Cotton, undelinted seed.........                 0.2                None
Cranberry.......................                 1.0            7/1/2025
Cucumber........................                0.05            7/1/2025
Egg.............................                0.01            7/1/2025
Fig.............................                0.01            7/1/2025
Fruit, citrus, group 10.........                 1.0                None
Food commodities (other than                     0.1            7/1/2025
 those already covered by a
 higher tolerance as a result of
 use on growing crops) in food
 service establishments where
 food and food products are
 prepared and served, as a
 result of the application of
 chlorpyrifos in
 microencapsulated form.........
Goat, fat.......................                 0.2                None
Goat, meat......................                0.05                None
Goat, meat byproducts...........                0.05                None
Hazelnut........................                 0.2            7/1/2025
Hog, fat........................                 0.2                None
Hog, meat.......................                0.05                None
Hog, meat byproducts............                0.05                None
Horse, fat......................                0.25                None
Horse, meat.....................                0.25                None
Horse, meat byproducts..........                0.25                None
Kiwifruit.......................                 2.0            7/1/2025
Milk, fat (Reflecting 0.01 ppm                  0.25                None
 in whole milk).................
Nectarine.......................                0.05            7/1/2025
Onion, bulb.....................                 0.5            7/1/2025
Peach...........................                0.05                None
Peanut..........................                 0.2            7/1/2025
Peanut, refined oil.............                 0.2            7/1/2025
Pear............................                0.05            7/1/2025
Pecan...........................                 0.2            7/1/2025
Pepper..........................                 1.0            7/1/2025
Peppermint, tops................                 0.8            7/1/2025
Peppermint, oil.................                 8.0            7/1/2025

[[Page 99206]]

 
Plum, prune, fresh..............                0.05            7/1/2025
Poultry, fat....................                 0.1                None
Poultry, meat...................                 0.1                None
Poultry, meat by products.......                 0.1                None
Pumpkin.........................                0.05            7/1/2025
Radish..........................                 2.0            7/1/2025
Rutabaga........................                 0.5            7/1/2025
Sheep, fat......................                 0.2                None
Sheep, meat.....................                0.05                None
Sheep, meat byproducts..........                0.05                None
Spearmint, tops.................                 0.8            7/1/2025
Spearmint, oil..................                 8.0            7/1/2025
Sorghum, grain, forage..........                 0.5            7/1/2025
Sorghum, grain, grain...........                 0.5            7/1/2025
Sorghum, grain, stover..........                 2.0            7/1/2025
Soybean, seed...................                 0.3                None
Strawberry......................                 0.2                None
Sunflower, seed.................                 0.1            7/1/2025
Sweet potato, roots.............                0.05            7/1/2025
Turnip, roots...................                 1.0            7/1/2025
Turnip, tops....................                 0.3            7/1/2025
Vegetable, brassica, leafy,                      1.0            7/1/2025
 group 5........................
Vegetable, legume, group 6,                     0.05            7/1/2025
 except soybean.................
Walnut..........................                 0.2            7/1/2025
Wheat, forage...................                 3.0                None
Wheat, grain....................                 0.5                None
Wheat, straw....................                 6.0                None
------------------------------------------------------------------------

    (2) Chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) 
phosphorothioate] may be safely used up until and including June 30, 
2025 in accordance with the following prescribed conditions. On and 
after July 1, 2025, chlorpyrifos may not be used as described below:
    (i) Application shall be limited solely to spot and/or crack and 
crevice treatment in food handling establishments where food and food 
products are held, processed, prepared or served. Contamination of food 
or food contact surfaces shall be avoided. Food must be removed or 
covered during treatment.
    (ii) Spray concentration for spot treatment shall be limited to a 
maximum of 0.5 percent of the active ingredient by weight. A course, 
low-pressure spray shall be used to avoid atomization or splashing of 
the spray.
    (iii) Paint-on application for spot treatment shall be limited to a 
maximum of 2 percent of the active ingredient by weight.
    (iv) Crack and crevice treatment shall be limited to a maximum of 2 
percent of the active ingredient by weight. Equipment capable of 
delivering a pin-stream of insecticide shall be used.
    (v) Application via adhesive strips shall contain a maximum of 10% 
by weight of the controlled-release product in food-handling 
establishments where food and food products are held, processed, 
prepared, or served. A maximum of 36 strips (or 5.15 grams of 
chlorpyrifos) is to be used per 100 square feet of floor space. The 
strips are not to be placed in exposed areas where direct contact with 
food, utensils, and food-contact surfaces would be likely to occur.
    (vi) To assure safe use of the insecticide, its label and labeling 
shall conform to that registered by the U.S. Environmental Protection 
Agency, and it shall be used in accordance with such label and 
labeling.
    (3) A tolerance of 0.1 part per million is established for residues 
of chlorpyrifos, per se, in or on food commodities (other than those 
already covered by a higher tolerance as a result of use on growing 
crops) in food service establishments where food and food products are 
prepared and served, as a result of the application of chlorpyrifos in 
microencapsulated form. This tolerance expires on July 1, 2025.
    (i) Application of a microencapsulated product shall be limited 
solely to spot and/or crack and crevice treatment in food handling 
establishments where food and food products are prepared and served. 
All treatments shall be applied in such a manner as to avoid 
contamination of food or food contact surfaces.
    (ii) Spray concentrations shall be limited to a maximum of 0.5 
percent of the active ingredient by weight.
    (iii) For crack and crevice treatment, equipment capable of 
delivering a pin stream of spray directly into cracks and crevices or 
capable of applying small amounts of insecticide into cracks and 
crevices shall be used.
    (iv) For spot treatment, an individual spot shall not exceed 2 
square feet.
    (v) To assure safe use of the insecticide, its label and labeling 
shall conform to that registered by the U.S. Environmental Protection 
Agency, and it shall be used in accordance with such label and 
labeling.
    (b) [Reserved]
    (c) Tolerances with regional registrations. Tolerances with 
regional registration, as defined in 180.1(l), are established for 
residues of the pesticide chlorpyrifos per se (O,O-diethyl- O-(3,5,6-
trichloro-2-pyridyl) phosphorothioate) in or on the following food 
commodities:

[[Page 99207]]



                        Table 2 to Paragraph (c)
------------------------------------------------------------------------
                                         Parts per         Tolerance
              Commodity                   million       expiration date
------------------------------------------------------------------------
Asparagus...........................             5.0                None
Grape...............................            0.01            7/1/2025
------------------------------------------------------------------------

    (d) [Reserved]

[FR Doc. 2024-28332 Filed 12-9-24; 8:45 am]
BILLING CODE 6560-50-P