Alachlor, Chlorothalonil, Methomyl, Metribuzin, Thiodicarb; Order Denying Petition To Revoke Tolerances, 43906-43924 [06-6605]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 71, Number 148 (Wednesday, August 2, 2006)]
[Rules and Regulations]
[Pages 43906-43924]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-6605]



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Part IV





Environmental Protection Agency





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40 CFR Part 180



Alachlor, Chlorothalonil, Methomyl, Metribuzin, Thiodicarb; Order 
Denying Petition To Revoke Tolerances; Final Rule

Federal Register / Vol. 71, No. 148 / Wednesday, August 2, 2006 / 
Rules and Regulations

[[Page 43906]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2005-0050; FRL-8079-8]


Alachlor, Chlorothalonil, Methomyl, Metribuzin, Thiodicarb; Order 
Denying Petition To Revoke Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Order.

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SUMMARY: In this Order, EPA denies, in part, a petition requesting the 
modification or revocation of the pesticide tolerances for alachlor, 
chlorothalonil, methomyl, metribuzin, and thiodicarb established under 
section 408 of the Federal Food, Drug, and Cosmetic Act (``FFDCA''). 
The petition was filed on December 17, 2004, by the States of New York, 
California, and Connecticut, and the Commonwealth of Massachusetts 
(``the States''). In their petition, the States contend that the risks 
posed by these pesticide tolerances must be assessed utilizing the 
additional tenfold (10X) safety factor for the protection of infants 
and children and that once this additional factor is included the 
challenged tolerances no longer meet the safety standard under FFDCA 
section 408. EPA is denying the petition to modify or revoke as to the 
tolerances for the pesticides alachlor, chlorothalonil, and metribuzin. 
EPA is deferring action on the petition as regards the tolerances for 
methomyl and thiodicarb given the ongoing Agency proceedings to address 
the safety of these pesticides.

DATES: This Order is effective August 2, 2006. Objections and requests 
for hearings must be received on or before October 2, 2006, and must be 
filed in accordance with the instructions provided in 40 CFR part 178 
(see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: EPA has established a docket for this action under Docket 
identification (ID) number EPA-HQ-OPP-2005-0050. All documents in the 
docket are listed in the index for the docket. Although listed in the 
index, some information is not publicly available, i.e., CBI or other 
information whose disclosure is restricted by statute. Certain other 
material, such as copyrighted material, is not placed on the Internet 
and will be publicly available only in hard copy form. Publicly 
available docket materials are available in the electronic docket at 
https://www.regulations.gov, or, if only available in hard copy, at the 
OPP Public Docket, in Rm. S-4400, One Potomac Yard (South Building), 
2777 S. Crystal Drive, Arlington, VA. This docket facility is open from 
8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays. 
The docket telephone number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Terria Northern, Special Review and 
Reregistration Division, (7508P), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: 703-305-7093; fax number: 
703-308-7070; e-mail address: northern.terria@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected entities may include, but are not limited to:
     Crop production (NAICS code 111)
     Animal production (NAICS code 112)
     Food manufacturing (NAICS code 311)
     Pesticide manufacturing (NAICS code 32532)
    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in this unit could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether this action might apply to certain entities. To determine 
whether you or your business may be affected by this action, you should 
carefully examine the applicability provisions in [insert appropriate 
cite to either another unit in the preamble or a section in a rule]. If 
you have any questions regarding the applicability of this action to a 
particular entity, consult the person listed under.

B. How Can I Access Electronic Copies of this Document?

    In addition to accessing an electronic copy of this Federal 
Register document through the electronic docket at https://
www.regulations.gov, you may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at https://www.epa.gov/fedrgstr. You may also access a 
frequently updated electronic version of 40 CFR part 180 through the 
Government Printing Office's pilot e-CFR site at https://
www.gpoaccess.gov/ecfr.

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of the FFDCA, as amended by the FQPA, any 
person may file an objection to any aspect of this regulation and may 
also request a hearing on those objections. The EPA procedural 
regulations which govern the submission of objections and requests for 
hearings appear in 40 CFR part 178. You must file your objection or 
request a hearing on this regulation in accordance with the 
instructions provided in 40 CFR part 178. To ensure proper receipt by 
EPA, you must identify docket ID number EPA-HQ-OPP-2006-0050 in the 
subject line on the first page of your submission. All requests must be 
in writing, and must be mailed or delivered to the Hearing Clerk on or 
before October 2, 2006.
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please submit a copy of 
the filing that does not contain any CBI for inclusion in the public 
docket that is described in ADDRESSES. Information not marked 
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA 
without prior notice. Submit your copies, identified by docket ID 
number EPA-HQ-OPP-2006-0050, by one of the following methods:
     Federal eRulemaking Portal. https://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail. Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery. OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Building), 2777 S. Crystal Drive, Arlington, VA. Deliveries are only 
accepted during the Docket's normal hours of operation (8:30 a.m. to 4 
p.m., Monday through Friday, excluding legal holidays). Special 
arrangements should be made for deliveries of boxed information. The 
Docket telephone number is (703) 305-5805.

II. Introduction

A. What Action Is the Agency Taking?

    In this Order, EPA denies, in part, a petition requesting the 
modification or revocation of the pesticide tolerances for alachlor, 
chlorothalonil, methomyl, metribuzin, and thiodicarb established under 
section 408 of the FFDCA. The petition was filed on December 17,

[[Page 43907]]

2004, by the States of New York, California, and Connecticut, and the 
Commonwealth of Massachusetts (``the States'') (Ref. 1). In their 
petition, the States contend that EPA is lacking data for each of the 
five pesticides on developmental neurotoxicity, endocrine effects, and/
or cumulative effects of exposure to pesticides with a common mechanism 
of toxicity. The States argue that this lack of these data mandates 
that EPA retain the additional tenfold (10X) safety factor for the 
protection of infants and children. The States further allege that once 
the 10X safety factor is retained, the challenged tolerances no longer 
meet the safety standard under FFDCA section 408 and must be modified 
or revoked.
    In today's Order, EPA is denying the petition to modify or revoke 
as to the tolerances for the pesticides alachlor, chlorothalonil, and 
metribuzin. As to alachlor and metribuzin, EPA is denying the petition 
because the tolerances for these pesticides would continue to meet the 
safety standard even if the additional 10X safety factor sought by the 
States is applied. For chlorothalonil, EPA has determined, after 
reviewing the legal and factual contentions of the States, that there 
is reliable data showing that the additional 10X safety factor is not 
needed to protect the safety of infants and children. EPA is deferring 
action on the petition as regards the tolerances for methomyl and 
thiodicarb given the ongoing Agency proceedings to address the safety 
of these pesticides.

B. What Is the Agency's Authority for Taking This Action?

    Under section 408(d)(4) of the FFDCA, EPA is authorized to respond 
to a section 408(d) petition to revoke tolerances either by issuing a 
final rule revoking the tolerances, issuing a proposed rule, or issuing 
an order denying the petition.

III. Statutory and Regulatory Background

A. Statutory Background

    1. In general. EPA establishes maximum residue limits, or 
``tolerances,'' for pesticide residues in food under section 408 of the 
FFDCA. (21 U.S.C. 346a). Without such a tolerance or an exemption from 
the requirement of a tolerance, a food containing a pesticide residue 
is ``adulterated'' under section 402 of the FFDCA and may not be 
legally moved in interstate commerce. (21 U.S.C. 331, 342). Monitoring 
and enforcement of pesticide tolerances are carried out by the U.S. 
Food and Drug Administration and the U. S. Department of Agriculture. 
Section 408 was substantially rewritten by the Food Quality Protection 
Act of 1996 (``FQPA''), which added the provisions discussed below 
establishing a detailed safety standard for pesticides, additional 
protections for infants and children, and the estrogenic substances 
screening program.
    EPA also regulates pesticides under the Federal Insecticide, 
Fungicide, and Rodenticide Act (``FIFRA''), (7 U.S.C. 136 et seq). 
While the FFDCA authorizes the establishment of legal limits for 
pesticide residues in food, FIFRA requires the approval of pesticides 
prior to their sale and distribution, (7 U.S.C. 136a(a)), and 
establishes a registration regime for regulating the use of pesticides. 
FIFRA regulates pesticide use in conjunction with its registration 
scheme by requiring EPA review and approval of pesticide labels and 
specifying that use of a pesticide inconsistent with its label is a 
violation of Federal law. (7 U.S.C. 136j(a)(2)(G)). In the FQPA, 
Congress integrated action under the two statutes by requiring that the 
safety standard under the FFDCA be used as a criterion in FIFRA 
registration actions as to pesticide uses which result in dietary risk 
from residues in or on food, (7 U.S.C. 136(bb)), and directing that EPA 
coordinate, to the extent practicable, revocations of tolerances with 
pesticide cancellations under FIFRA. (21 U.S.C. 346a(l)(1)).
    2. Safety standard for pesticide tolerances. A pesticide tolerance 
may only be promulgated by EPA if the tolerance is ``safe.'' (21 U.S.C. 
346a(b)(2)(A)(i)). ``Safe'' is defined by the statute 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)). Section 
408(b)(2)(D) directs EPA, in making a safety determination, to:
     consider, among other relevant factors- . . . .
     (v) available information concerning the cumulative effects of 
such residues and other substances that have a common mechanism of 
toxicity; . . .
     (vi) available information concerning the aggregate exposure 
levels of consumers (and major identifiable subgroups of consumers) 
to the pesticide chemical residue and to other related substances, 
including dietary exposure under the tolerance and all other 
tolerances in effect for the pesticide chemical residue, and 
exposure from other non-occupational sources.
     (viii) such information as the Administrator may require on 
whether the pesticide chemical may have an effect in humans that is 
similar to an effect produced by a naturally occurring estrogen or 
other endocrine effects. . . .
(21 U.S.C. 346a(b)(2)(D)(v), (vi) and (viii)).
    Section 408(b)(2)(C) requires EPA to give special consideration to 
risks posed to infants and children. Specifically, this provision 
states that EPA:
     shall assess the risk of the pesticide chemical based on-- . . 
.
     (II) available information concerning the special 
susceptibility of infants and children to the pesticide chemical 
residues, including neurological differences between infants and 
children and adults, and effects of in utero exposure to pesticide 
chemicals; and
     (III) available information concerning the cumulative effects 
on infants and children of such residues and other substances that 
have a common mechanism of toxicity. . . .
(21 U.S.C. 346a(b)(2)(C)(i)(II) and (III)).
This provision further directs that ``[i]n 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.). [The additional safety 
margin for infants and children is referred to throughout this Order as 
the ``children's safety factor.'']
    3. Procedures for establishing, amending, or revoking tolerances. 
Tolerances are established, amended, or revoked by rulemaking under the 
unique procedural framework set forth in the FFDCA. Generally, the 
rulemaking is initiated by the party seeking to establish, amend, or 
revoke a tolerance by means of filing a petition with EPA. (See 21 
U.S.C. 346a(d)(1)). EPA publishes in the Federal Register a notice of 
the petition filing and requests public comment. (21 U.S.C. 
346a(d)(3)). After reviewing the petition, and any comments received on 
it, EPA may issue a final rule establishing, amending, or revoking the 
tolerance, issue a proposed rule to do the same, or deny the petition. 
(21 U.S.C. 346a(d)(4)). Once EPA takes final action on the petition by 
either establishing, amending, or revoking the tolerance or denying the 
petition, any affected party has 60 days to file objections with EPA 
and seek an evidentiary hearing on those objections. (21 U.S.C. 
346a(g)(2)). EPA's final order on the objections is subject to judicial 
review. (21 U.S.C. 346a(h)(1)).
    4. Estrogenic Substances Screening Program. Section 408(p) of the 
FFDCA

[[Page 43908]]

creates the estrogenic substances screening program. This provision 
gives EPA 2 years from enactment of the FQPA to ``develop a screening 
program . . . to determine whether certain substances may have an 
effect in humans that is similar to an effect produced by a naturally 
occurring estrogen, or such other endocrine effect as the Administrator 
may designate.'' This screening program must use ``appropriate 
validated test systems and scientifically relevant information.'' (21 
U.S.C. 346a(p)(1)). Once the program is developed, EPA is required to 
take public comment and seek independent scientific review of it. 
Following the period for public comment and scientific review, and not 
later than 3 years following enactment of the FQPA, EPA is directed to 
``implement the program.'' (21 U.S.C. 346a(p)(2)).
    The scope of the estrogenic screening program was expanded by an 
amendment to the Safe Drinking Water Act (SDWA) passed 
contemporaneously with FQPA. That amendment gave EPA the authority to 
provide for the testing, under the FQPA estrogenic screening program, 
``of any other substance that may be found in sources of drinking water 
if the Administrator determines that a substantial population may be 
exposed to such substance.'' (42 U.S.C. 300j-17).

B. Setting and Reassessing Pesticide Tolerances Under the FFDCA

    1. In general. The process EPA follows in setting and reassessing 
tolerances under the FFDCA includes two steps. First, EPA determines an 
appropriate residue level value for the tolerance taking into account 
data on levels that can be expected in food. Second, EPA evaluates the 
safety of the tolerance relying on toxicity and exposure data and 
guided by the statutory definition of ``safety'' and requirements 
concerning risk assessment. Only on completion of the second step can a 
tolerance be established or reassessed. This bifurcation between 
selection of a tolerance level and evaluation of the safety of a 
tolerance has ramifications on how EPA responds when a tolerance is 
found to no longer meet section 408's safety standard. Generally, if an 
existing tolerance is shown to raise safety concerns, EPA would not 
address these concerns by modifying the tolerance through decreasing 
the tolerance level unless there were pesticide residue data showing 
how such a lower level could be achieved. Rather, where safety concerns 
are demonstrated and there is no available data demonstrating that a 
different application pattern would produce lower residue levels in 
food, the only appropriate action would be to revoke the tolerance. 
Below, EPA explains in detail, the reasons for this approach.
    2. Choosing a tolerance value. In the first step of the tolerance 
setting or reassessment process (choosing a tolerance value), EPA 
evaluates data from experimental crop field trials in which the 
pesticide has been used in a manner, consistent with the draft FIFRA 
label, that is likely to produce the highest residue in the crop in 
question (e.g., maximum application rate, maximum number of 
applications, minimum pre-harvest interval between last pesticide 
application and harvest). (Refs. 2 and 3). These crop field trials are 
generally conducted in several fields at several geographical 
locations. (Ref. Id. at 5, 7 and Tables 1 and 5). Several samples are 
then gathered from each field and analyzed. (Id. at 53). Generally, the 
results from such field trials show that the residue levels for a given 
pesticide use will vary from as low as non-detectable to measurable 
values in the parts per million (ppm) range with the majority of the 
values falling at the lower part of the range. EPA then chooses a value 
to be used in the tolerance by identifying the highest residue value 
found and rounding that value up or adding a small increment to it. 
(See 70 FR 46706, 46731, August 10, 2005). (As discussed below, the 
safety of the tolerance value chosen is separately evaluated.).
    There are three main reasons for closely linking tolerance values 
to the maximum value that could be present from maximum label usage of 
the pesticide. First, EPA believes it is important to coordinate its 
actions under the two statutory frameworks governing pesticides. (See 
The Pesticide Coordination Policy; Response to Petitions, (61 FR 2378, 
2379; January 25, 1996)). It would be illogical for EPA to set a 
pesticide tolerance under the FFDCA without considering what action is 
being taken under FIFRA with regard to registration of that pesticide 
use. (Cf. 40 CFR 152.112(g) (requiring all necessary tolerances to be 
in place before a FIFRA registration may be granted)). In coordinating 
its actions, one basic tenet that EPA follows is that a grower who 
applies a pesticide consistent with the FIFRA label directions should 
not run the risk that his or her crops will be adulterated under the 
FFDCA because the residues from that legal application exceed the 
tolerance associated with that use. Crop field trials require 
application of the pesticide in the manner most likely to produce 
maximum residues to further this goal. Second, choosing tolerance 
values based on FIFRA label rates helps to ensure that tolerance levels 
are established no higher than necessary. If tolerance values were 
selected solely in consideration of health risks, in some 
circumstances, tolerance values might be set so as to allow much 
greater application rates than necessary for effective use of the 
pesticide. This could encourage misuse of the pesticide. Finally, 
closely linking tolerance values to FIFRA labels helps EPA to police 
compliance with label directions by growers because detection of an 
overtolerance residue is indicative of use of a pesticide at levels, or 
in a manner, not permitted on the label.
    3. The safety determination - risk assessment. Once a tolerance 
value is chosen, EPA then evaluates the safety of the pesticide 
tolerance using the process of risk assessment. To assess risk of a 
pesticide, EPA combines information on pesticide toxicity with 
information regarding the route, magnitude, and duration of exposure to 
the pesticide.
    In evaluating toxicity or hazard, EPA examines both short-term 
(e.g., ``acute'') and longer-term (e.g., ``chronic'') adverse effects 
from pesticide exposure. (Ref. 2 at 8-10). EPA also considers whether 
the ``effect'' has a threshold - a level below which exposure has no 
appreciable chance of causing the adverse effect. For non-threshold 
effects, EPA assumes that any exposure to the substance increases the 
risk that the adverse effect may occur. At present, EPA only considers 
one adverse effect, the chronic effect of cancer, to potentially be a 
non-threshold effect. (Ref. 2 at 8-9). Not all carcinogens, however, 
pose a risk at any exposure level (i.e., ``a non-threshold effect or 
risk''). Advances in the understanding of carcinogenesis have 
increasingly led EPA to conclude that some pesticides that cause 
carcinogenic effects only cause such effects above a certain threshold 
of exposure. EPA has traditionally considered adverse effects on the 
endocrine system to be a threshold effect; that determination is being 
reexamined in conjunction with the endocrine disruptor screening 
program.
    Once the hazard for a durational scenario is identified, EPA must 
determine the toxicological level of concern and then compare estimated 
human exposure to this level of concern. This comparison is done 
through either calculating a safe dose in humans (incorporating all 
appropriate safety factors) and expressing exposure as a percentage of 
this safe dose (the reference dose (``RfD'') approach) or dividing 
estimated human exposure into

[[Page 43909]]

an appropriate dose from the relevant studies at which no adverse 
effects from the pesticide are seen (the margin of exposure (``MOE'') 
approach). How EPA determines the level of concern and assesses risk 
under these two approaches is explained in more detail below. EPA's 
general approach to estimating exposure is also briefly discussed.
    a. Levels of concern and risk assessment--(i) threshold effects. In 
assessing the risk from a pesticide's threshold effects, EPA evaluates 
an array of toxicological studies on the pesticide. In each of these 
studies, EPA attempts to identify the lowest observed adverse effect 
level (``LOAEL'') and the next lower dose at which there are no 
observed adverse affect levels (``NOAEL''). Generally, EPA will use the 
lowest NOAEL from the available studies as a starting point in 
estimating the level of concern for humans. In estimating and 
describing the level of concern, however, the chosen NOAEL is at times 
manipulated differently depending on whether the risk assessment 
addresses dietary or non-dietary exposures.
    For dietary risks, EPA uses the chosen NOAEL to calculate a safe 
dose or RfD. The RfD is calculated by dividing the chosen NOAEL by all 
applicable safety or uncertainty factors. Typically, a combination of 
safety or uncertainty factors providing a hundredfold (100X) margin of 
safety is used: 10X to account for uncertainties inherent in the 
extrapolation from laboratory animal data to humans and 10X for 
variations in sensitivity among members of the human population as well 
as other unknowns. Further, under the FQPA, an additional safety factor 
of 10X is presumptively applied to protect infants and children, unless 
reliable data support selection of a different factor.
    To quantitatively describe risk using the RfD approach, estimated 
exposure is expressed as a percentage of the RfD. Dietary exposures 
lower than 100 percent of the RfD are generally not of concern. Further 
complicating matters, EPA's Office of Pesticide Programs, in 
implementing FFDCA section 408, also calculates a variant of the RfD 
referred to as a Population Adjusted Dose (``PAD''). A PAD is the RfD 
divided by any portion of the FQPA safety factor that does not 
correspond to one of the traditional additional safety factors used in 
general Agency risk assessment. (Ref. 4 at 13-16). The reason for 
calculating PADs is so that other parts of the Agency, which are not 
governed by FFDCA section 408, can, when evaluating the same or similar 
substances, easily identify which aspects of a pesticide risk 
assessment are a function of the particular statutory commands in FFDCA 
section 408. For simplicity, this document refers to all safe dose 
calculations as RfDs. Today, RfDs are generally calculated for both 
acute and chronic dietary risks although traditionally a RfD was only 
calculated for chronic dietary risks.
    For non-dietary, and often for combined dietary and non-dietary, 
risk assessments of threshold effects, the toxicological level of 
concern is not expressed as a safe dose or RfD but rather as the margin 
of exposure (MOE) that is necessary to be sure that exposure to a 
pesticide is safe. A safe 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, if a pesticide needs a 10X factor to account 
for interspecies differences, 10X factor for intraspecies differences, 
and 10X factor for FQPA, the safe or target MOE would be a MOE of at 
least 1,000. To calculate the MOE for a pesticide, human exposure to 
the pesticide is divided into the lowest NOAEL from the available 
studies. In contrast to the RfD approach, the higher the MOE, the safer 
the pesticide. Accordingly, if the level of concern for a pesticide is 
1,000, MOE's exceeding 1,000 would generally not be of concern. Like 
RfDs, specific MOEs are calculated for exposures of different 
durations. For non-dietary exposures, EPA typically examines short-
term, intermediate-term, and long-term exposures. Additionally, non-
dietary exposure often involves exposures by various routes including 
dermal, inhalation, and oral.
    The RfD and MOE approaches are fundamentally equivalent. For a 
given risk and given exposure of a pesticide, if the pesticide were 
found to be safe under a RfD analysis it would also pass under the MOE 
approach, and vice-versa.
    (ii) Non-threshold effects. For risk assessments for non-threshold 
effects, EPA does not use the RfD or MOE approach. Rather, EPA 
calculates the slope of the dose-response curve for the non-threshold 
effects from relevant studies using a model that assumes that any 
amount of exposure will lead to some degree of risk. The slope of the 
dose-response curve can then be used to estimate the probability of 
occurrence of additional adverse effects as a result of exposure to the 
pesticide. For non-threshold cancer risks, EPA generally is concerned 
if the probability of increased cancer cases exceed the range of 1 in 1 
million. Because the States' petition concerns the children's safety 
factor and the children's safety factor is only applicable to threshold 
risks, no further discussion of non-threshold risk assessment is 
included here.
    b. Estimating human exposure. Equally important to the risk 
assessment process as determining the toxicological level of concern is 
estimating human exposure. Under FFDCA section 408, EPA is concerned 
not only with exposure to pesticide residues in food but also exposure 
resulting from pesticide contamination of drinking water supplies and 
from use of pesticides in the home or other non-occupational settings. 
(See 21 U.S.C. 346a(b)(2)(D)(vi)). The focus of the States' petition, 
however, appears to be on pesticide exposure from food. 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. (Ref. 2 at 12). Information on residue 
values comes from a range of sources including crop field trials, data 
on pesticide reduction due to processing and other practices, 
information on the extent of usage of the pesticide, and monitoring of 
the food supply. (Id. at 17).
    In assessing exposure from pesticide residues in food, EPA, for 
efficiency's sake, follows a tiered approach in which it, in the first 
instance, conducts its exposure assessment using the worst case 
assumptions that 100 percent of the crop in question is treated with 
the pesticide and 100 percent of the food from that crop contains 
pesticide residues at the tolerance level. (Id. at 11). When such an 
assessment shows no risks of concern, EPA's resources are conserved 
because a more complex risk assessment is avoided and regulated parties 
are spared the cost of any additional studies that may be needed. If, 
however, a first tier assessment suggests there could be a risk of 
concern, EPA then attempts to refine its exposure assumptions to yield 
a more realistic picture of residue values through use of data on the 
percent of the crop actually treated with the pesticide and data on the 
level of residues that may be present on the treated crop. These latter 
data are used to estimate what has been traditionally referred to by 
EPA as ``anticipated residues.''
    Use of percent crop treated data and anticipated residue 
information is appropriate because EPA's worst case assumptions of 100 
percent treatment and residues at tolerance value significantly 
overstate residue values. There are several reasons this is true.

[[Page 43910]]

 First, all growers of a particular crop would rarely choose to apply 
the same pesticide to that crop; generally, the proportion of the crop 
treated with a particular pesticide is significantly below 100 percent. 
Second, as discussed above, the tolerance value is set above the 
highest value observed in crop field trials using maximum use rates. 
There may be some commodities from a treated crop that approach the 
tolerance value where the maximum label rates are followed, but most 
generally fall significantly below. If less than the maximum legal rate 
is applied, residues will be even lower. Third, residue values in the 
field do not take into account the lowering of residue values that 
frequently occurs as a result of degradation over time and through food 
processing and cooking.
    EPA uses several techniques to refine residue value estimates. (Id. 
at 17-28). First, where appropriate, EPA will take into account all the 
residue values reported in the crop field trials, either through use of 
an average or individually. Second, EPA will consider data showing what 
portion of the crop is not treated with the pesticide. Third, data can 
be produced showing pesticide degradation and decline over time, and 
the effect of commercial and consumer food handling and processing 
practices. Finally, EPA can consult monitoring data gathered by the 
Food and Drug Administration, the U.S. Department of Agriculture, or 
pesticide registrants, on pesticide levels in food at points in the 
food distribution chain distant from the farm, including retail food 
establishments.
    Another critical component of the exposure assessment is how data 
on consumption patterns are combined with data on pesticide residue 
levels in food. Traditionally, EPA has calculated exposure by simply 
multiplying high-end consumption by average residue values for 
estimating chronic risks and high-end consumption by maximum residue 
values for estimating acute risks. Although using average residues is a 
realistic approach for chronic risk assessment due to the fact that 
variations in residue levels and consumption amounts average out over 
time, using maximum residue values for acute risk assessment tends to 
greatly overstate exposure in narrow increments of time where it 
matters how much of each treated food a given consumer eats and what 
the residue levels are in the particular foods consumed. To take into 
account the variations in short-term consumption patterns and food 
residue values for acute risk assessments, EPA has more recently begun 
using probabilistic modeling techniques for estimating exposure when 
more simplistic models appear to show risks of concerns.
    All of these refinements to the exposure assessment process, from 
use of food monitoring data through probabilistic modeling, can have 
dramatic effects on the level of exposure predicted, reducing worst 
case estimates by 1 or 2 orders of magnitude or more.

C. EPA Policy on the Children's Safety Factor

    As the above brief summary of EPA's risk assessment practice 
indicates, the use of safety factors plays a critical role in the 
process. This is true for traditional 10X safety factors to account for 
differences between animals and humans when relying on studies in 
animals (inter-species safety factor) and differences among humans 
(intra-species safety factor) as well as the additional 10X children's 
safety factor added by the FQPA.
    In applying the children's safety factor provision, EPA has 
interpreted it as imposing a presumption in favor of applying an 
additional 10X safety factor. (Ref. 4 at 4, 11). Thus, EPA generally 
refers to the additional 10X factor as a presumptive or default 10X 
factor. EPA has also made clear, however, that this presumption or 
default in favor of the additional 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 
mentioned in 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 safety factor, based on a weight-of-the-
evidence evaluation, does not understate the risk to children. (Id. at 
24-25, 35). EPA's implementation of the safety factor provision is 
explained in greater detail in Unit VII.D.1.c.

D. Endocrine Disruptor Screening Program

    To aid in the design of the endocrine screening program called for 
in the FQPA and SDWA amendments, EPA created the Endocrine Disruptor 
Screening and Testing Advisory Committee (EDSTAC), which was comprised 
of members representing the commercial chemical and pesticides 
industries, Federal and State agencies, worker protection and labor 
organizations, environmental and public health groups, and research 
scientists. (63 FR 71542, 71544, Dec. 28, 1998). The EDSTAC presented a 
comprehensive report in August 1998 addressing both the scope and 
elements of the endocrine screening program. (Ref. 5). The EDSTAC's 
recommendations were largely adopted by EPA.
    As recommended by EDSTAC, EPA expanded the scope of the program 
from focusing only on estrogenic effects to include androgenic and 
thyroid effects as well. (63 FR at 71545). Further, EPA, again on the 
EDSTAC's recommendation, chose to include both human and ecological 
effects in the program. (Id.). Finally, based on EDSTAC's 
recommendation, EPA established the universe of chemicals to be 
screened to include not just pesticides but some 87,000 chemical 
substances and common mixtures. (Id.). As to the program elements, EPA 
adopted EDSTAC's recommended two-tier approach with the first tier 
involving screening ``to identify substances that have the potential to 
interact with the endocrine system'' and the second tier involving 
testing ``to determine whether the substance causes adverse effects, 
identify the adverse effects caused by the substance, and establish a 
quantitative relationship between the dose and the adverse effect.'' 
(Id.). Tier 1 screening is limited to evaluating whether a substance is 
``capable of interacting with'' the endocrine system, and is ``not 
sufficient to determine whether a chemical substance may have an effect 
in humans that is similar to an effect produced by naturally occurring 
hormones.'' (Id. at 71550). Based on the results of Tier 1 screening, 
EPA will decide whether Tier 2 testing is needed. Importantly, ``[t]he 
outcome of Tier 2 is designed to be conclusive in relation to the 
outcome of Tier 1 and any other prior information. Thus, a negative 
outcome in Tier 2 will supersede a positive outcome in Tier 1.'' (Id. 
at 71554-71555).
    The EDSTAC provided detailed recommendations for Tier 1 screening 
and Tier 2 testing. The panel of the EDSTAC that devised these 
recommendations was comprised of distinguished scientists from 
academia, government, industry, and the environmental community. (Ref. 
5, Appendix B). As suggested by the EDSTAC, EPA has proposed a battery 
of short-term in vitro and in vivo assays for the Tier 1 screening 
exercise. (63 FR at 71550-71551). Validation of these assays, however, 
has proved difficult and, more than 7 years after proposing the assays, 
validation of all of the assays in the battery is not yet complete. As 
to Tier 2 testing, EPA, on the recommendation of the EDSTAC, has

[[Page 43911]]

proposed using five longer-term reproduction studies that, with one 
exception, ``are routinely performed for pesticides with widespread 
outdoor exposures that are expected to affect reproduction.'' (Id. at 
71555). EPA is examining, pursuant to the suggestion of the EDSTAC, 
modifications to these studies to enhance their ability to detect 
endocrine effects.

E. Lawsuit Seeking the Revocation of Tolerances

    In 2003, the States of New York, New Jersey, Connecticut, and 
Massachusetts, filed suit against EPA seeking the revocation of the 
same pesticide tolerances challenged in this petition. The lawsuit, 
containing allegations nearly identical to those in this petition, 
argued that EPA's tolerance reassessment decisions as to alachlor, 
chlorothalonil, methomyl, metribuzin, and thiodicarb were in violation 
of FFDCA section 408. In 2004, this lawsuit was dismissed because the 
plaintiffs had not first presented their challenge to these tolerances 
to EPA in the form of section 408(d)(4) petition to revoke. (New York 
v. EPA, 350 F. Supp. 429 (S.D.N.Y. 2004)). The current petition was 
subsequently filed with EPA.

IV. The Challenged Tolerances

A. Alachlor

    Alachlor is a selective herbicide used in agriculture for the 
control of broadleaf weeds and grasses. Alachlor is registered under 
FIFRA for use on corn, soybeans, sorghum, peanuts, and beans and 37 
FFDCA tolerances are currently associated with those uses. (40 CFR 
180.249).
    In December 1998, EPA released a RED for alachlor finding it 
eligible for reregistration. (Ref. 6). The RED also reassessed 
alachlor's tolerances concluding that 22 met the requirements of 
section 408 but that 16 would have to be revised or revoked. (Id. at 
184-187; Ref. 7). (The current number of tolerances for alachlor and 
the other five pesticides may not match the number of reassessed 
tolerances due to subsequent actions to establish or revoke tolerances 
as well as to a generic administrative action amending tolerance 
nomenclature. (68 FR 39428, July 1, 2003)). The RED found that alachlor 
posed chronic and cancer risks as a result of dietary exposure but not 
any acute risk. The RfD, or safe dose, for chronic exposure was based 
on a chronic dog study in which hemosiderosis and hemolytic anemia were 
observed. (Ref. 6 at 39). Cancer studies revealed that alachlor caused 
nasal, gastric, and thyroid tumors in the rat. A chronic dietary risk 
assessment found that exposure to alachlor from food and drinking water 
posed minimal risks. The subgroup facing the highest risk from food is 
non-nursing infants < 1 year at 0.5 percent of the RfD. (Id. at 85). 
For drinking water, the highest risk is posed to children 1-6 years at 
2 percent of the RfD. (Id. at 87). The highest aggregate risk was 4 
percent of the RfD for children 1-6 years. (Id. at 91). Cancer risks 
were found to be negligible. (Id. at 91-94). These risk assessments 
were based on moderately conservative exposure assumptions that relied 
on crop field trial data and information of the percentage of the crop 
treated with alachlor for some crops. (Id. at 83-84).
    EPA removed the 10X children's safety factor based on its 
determination that (1) The toxicology database was complete; (2) the 
toxicology data showed no evidence of neurotoxicity and thus there was 
no need for a developmental neurotoxicity study for alachlor; (3) the 
toxicology data showed no evidence of increased susceptibility in the 
young; and (4) the exposure estimate was unlikely to understate 
exposure to infants and children. (Id. at 50). In the RED, EPA noted 
that alachlor is structurally similar to other chloroacetanilide 
pesticides (acetochlor, butachlor, propachlor, and metolachlor) and may 
share a common mechanism of toxicity with some or all of these 
pesticides. (Id. at 112). EPA indicated that no determination on this 
issue had been made at that time. (Id.). Subsequently, EPA did conclude 
that alachlor, acetochlor and butachlor share a common mechanism of 
toxicity with respect to the causation of nasal turbinate tumors. (Ref. 
8). EPA has also now completed a cumulative cancer risk assessment for 
these pesticides that shows no risk of concern. (Ref. 9). Finally, the 
RED indicated that alachlor does have effects on the endocrine system 
in that it disrupts the hormone balance leading to the formation of 
thyroid tumors. (Ref. 6 at 31). Subsequently, EPA determined that these 
endocrine effects only occurred at high doses which were well above any 
exposure levels humans would face from pesticidal uses of alachlor. 
(Ref. 8).

B. Chlorothalonil

    Chlorothalonil is a broad spectrum, non-systemic protectant 
pesticide mainly used as a fungicide to control fungal foliar diseases 
of vegetable, field, and ornamental crops. In connection with these 
uses there are 66 FFDCA tolerances currently established for 
chlorothalonil. (40 CFR 180.275).
    In April 1999, EPA released a RED for chlorothalonil finding it 
eligible for reregistration so long as various uses were prohibited and 
numerous risk mitigation steps were taken. (Ref. 10 at v-vi). The RED 
also reassessed chlorothalonil's tolerances concluding that all met the 
requirements of section 408 except one that would have to be raised. 
Further, an additional tolerance was found to be necessary in 
connection with one use site. (Id. at 171-174; Ref. 7 at 58-59). The 
RED found that chlorothalonil posed acute, chronic and cancer risks as 
a result of dietary exposure. The RfD, or safe dose, for chronic 
exposure was based on a chronic rat study in which increased kidney 
weights and hyperplasia were observed. (Ref. 10 at 21). EPA evaluated 
acute risk based on the LOAEL from a subchronic rat study showing 
lesions and hyperplasia. (66 FR 56233, 56235, Nov. 7, 2001). Because no 
NOAEL was identified in this study EPA added an extra 3X safety factor. 
(Ref. 10 at 23). Cancer studies revealed that chlorothalonil caused 
renal adenomas and carcinomas in the rat and mouse. An aggregate 
chronic dietary risk assessment found that exposure to chlorothalonil 
from food and drinking water would utilize 68 percent of the RfD for 
children 1-6, the most highly-exposed subgroup. (Id. at 100). EPA 
concluded that there was a MOE of 310 for adults (the highest exposed 
subgroup) with regard to aggregate acute risk. (Id.). The target or 
safe MOE was 300. Cancer risks were found to be negligible. (Id. at 
161-162). The acute and cancer risk assessments were based on 
relatively refined exposure assumptions including percent crop treated 
data on most crops and anticipated residue data based on field trial 
data or food monitoring data. The chronic risk assessment was more 
conservative in that it only relied upon percent crop treated 
information. (Id. at 36-41).
    Other than retaining an additional 3X safety factor as to acute 
risks, EPA removed the 10X children's safety factor for chlorothalonil 
based on its determination that (1) the toxicology database was 
complete; (2) the toxicology data showed no evidence of increased 
susceptibility in the young; and (3) the exposure estimate was unlikely 
to understate exposure to infants and children. (Id. at 170; 66 FR at 
56242). In the RED, EPA noted that chlorothalonil is a member of the 
polychlorinated fungicide class of pesticides which includes 
hexachlorobenzene, pentachlorophenol, and pentachloronitrobenzene. 
(Ref. 10 at

[[Page 43912]]

100). EPA indicated that no determination on the issue of common 
mechanism of toxicity had been made at that time. (Id.).

C. Methomyl

    Methomyl is an insecticide registered on a wide variety of sites 
including field, vegetable, and orchard crops; turf (sod farms only); 
livestock quarters; commercial premises; and refuse containers. There 
are 78 FFDCA tolerances currently associated with these uses. (40 CFR 
180.253).
    In December 1998, EPA released a RED for methomyl finding it 
eligible for reregistration. (Ref. 11). The RED also reassessed 
methomyl's tolerances concluding that 65 met the requirements of 
section 408 but that 15 would have to be revised or revoked. (Id. at 
103-111; Ref. 7 at 175-176). The RED found that methomyl posed chronic 
and acute risks as a result of dietary exposure. The RfD, or safe dose, 
for chronic exposure was based on a chronic dog study in which 
histopathological effects in the kidney were observed. (Ref. 11 at 24). 
EPA evaluated acute risk based on a rabbit developmental study that 
showed deaths in the dams on days 1-3 after dosing. (Id. at 25). 
Aggregate risks from methomyl were assessed taking into account that 
another pesticide, thiodicarb, degrades into methomyl and thus serves 
as another source of exposure to the compound. A chronic dietary risk 
assessment found that exposure to methomyl from food utilized no 
greater than 7 percent of the RfD for any subgroup. (Id. at 35). EPA 
concluded that there was a MOE of 417 for children 1-6 years (the 
highest exposed subgroup) with regard to acute risk from residues in 
food. (Id. at 37). Exposure to methomyl in drinking water was not 
expected to make either of these risk estimates exceed the level of 
concern. (Id. at 38). These risk assessments were based on moderately 
conservative exposure assumptions that relied on crop field trial data 
and information of the percentage of the crop treated with methomyl. 
(Id. at 35-36).
    EPA reduced the 10X children's safety factor to 3X for methomyl. 
Although the data provided no indication of increased sensitivity of 
rats or rabbits to in utero or postnatal exposure to methomyl, there 
were data gaps for acute and subchronic neurotoxicity studies. (Id. at 
24). In the RED, EPA indicated that no determination as to whether 
methomyl shared a common mechanism of toxicity with other substances 
had been made at that time. (Id. at 55-56). Subsequently, EPA did 
conclude that methomyl shares a common mechanism of toxicity with other 
N-methyl carbamate pesticides. (Ref. 8). EPA is re-examining the safety 
finding it made for methomyl in light of this conclusion. EPA has 
completed a preliminary cumulative risk assessment for the N-methyl 
carbamates. EPA expects to finish this cumulative risk assessment and 
make a safety determination as to all of the N-methyl carbamates in the 
near future.

D. Metribuzin

    Metribuzin is a herbicide used on a wide range of sites, including 
vegetable and field crops, turf grasses (recreational areas), and non-
crop areas, to selectively control certain broadleaf weeds and grassy 
weed species. In connection with these uses there are 61 FFDCA 
tolerances currently established for metribuzin (40 CFR 180.332).
    In February 1999, EPA released a RED for metribuzin finding it 
eligible for reregistration based on various risk mitigation steps 
proposed by the registrant. (Ref. 12 at iv). The RED also reassessed 
metribuzin's tolerances concluding that 22 met the requirements of 
section 408 but that 38 would have to be revised or revoked. (Id. at 
101-107; Ref. 7 at 187-188). The RED found that metribuzin posed acute 
and chronic risks as a result of dietary exposure. The RfD, or safe 
dose, for chronic exposure was based on a chronic rat study which 
showed increased thyroid weight, decreased lung weight, and increases 
of certain enzyme levels in blood. (Ref. 12 at 16). EPA evaluated acute 
risk based on the NOAEL from a developmental rabbit study showing 
decreased fetal body weight, increased number of runts, and increased 
incidence of extra and partial ribs. (Id. at 17). An aggregate chronic 
dietary risk assessment found that exposure to metribuzin from food and 
drinking water would utilize 79 percent of the RfD for children 1-6, 
the most highly-exposed subgroup. (Id. at 54). EPA concluded that there 
was a MOE of 1,200 for females 13-50 years (the highest exposed 
subgroup) with regard to aggregate acute risk. (Id. at 52). These risk 
assessments were based on the extremely conservative exposure 
assumptions that all commodities covered by the tolerances were treated 
with metribuzin and the residue levels were at the tolerance level. 
(Id. at 39-40).
    EPA removed the 10X children's safety factor for metribuzin based 
on its determination that the toxicology database was complete and it 
showed no evidence of increased susceptibility in the young. (Id. at 
51). In the RED, EPA indicated that no determination as to whether 
metribuzin shared a common mechanism of toxicity with other substances 
had been made at that time. (Id. at 55-56).

E. Thiodicarb

    Thiodicarb is an insecticide used primarily on cotton, sweet corn, 
and soybeans. It is also registered for use on leafy vegetables, cole 
crops, ornamentals, and other minor use sites. In connection with these 
uses there are nine FFDCA tolerances currently established for 
thiodicarb. (40 CFR 180.407).
    In December 1998, EPA released a RED for thiodicarb finding it 
eligible for reregistration. (Ref. 13). The RED also reassessed 
thiodicarb's tolerances concluding that 6 met the requirements of 
section 408 but that 34 would have to be revised or revoked. (Id. at at 
89-91). The RED found that thiodicarb posed chronic, acute, and cancer 
risks as a result of dietary exposure. The RfD, or safe dose, for 
chronic exposure was based on a chronic rat study in which increased 
incidence of extramedullary hemopoiesis and decreased RBC 
cholinesterase were observed. (Ref. 13 at 20). EPA evaluated acute risk 
based on a rabbit developmental study that showed decreased body weight 
and increased developmental variations in the fetuses and a rat 
developmental study that found decreased body-weight gain in the dams. 
(Id. at 16, 21). Cancer studies showed that thiodicarb caused liver 
tumors in mice and testicular tumors in rats. Aggregate risks from 
thiodicarb were assessed taking into account that thiodicarb degrades 
into methomyl, another pesticide, and thus both pesticides serve as a 
source of exposure to the compound. A chronic dietary risk assessment 
found that exposure to thiodicarb from food utilized 104 percent of the 
RfD for the most highly-exposed subgroup, children 1-6 years. Although 
the exposure for this subgroup slightly exceeded the RfD, EPA concluded 
that this exposure estimate was significantly overstated because it 
assumed all treated crops had residues at the tolerance level. (Id. at 
29). Cancer risks were found to be negligible. (Id. at 30). EPA 
concluded that there was a MOE of 1,680 for infants (the most highly-
exposed subgroup) with regard to acute risk from residues in food. (Id. 
at 31). Exposure to thiodicarb in drinking water was not expected to 
make any of these risk estimates exceed the level of concern. (Id. at 
33). The chronic risk assessment was based on very conservative 
exposure assumptions that relied on information of the percentage of 
the crop treated with thiodicarb and assumed residues were present at 
the tolerance level. (Id. at 29). The cancer

[[Page 43913]]

risk assessment and acute risk assessments used the less conservative 
approach of relying on percent crop treated data and anticipated 
residue data. (Id. at 30). Risk assessments for combined exposure to 
methomyl as a result of the use of thiodicarb and methomyl were 
identical to the risk assessments in the methomyl RED.
    EPA reduced the 10X children's safety factor to 3X for thiodicarb. 
Although the data provided no indication of increased sensitivity of 
rats or rabbits to in utero or postnatal exposure to thiodicarb, there 
were data gaps for acute and subchronic neurotoxicity studies as to 
methomyl, a thiodicarb degradate. (Id. at 19). In the RED, EPA 
indicated that no determination as to whether thiodicarb shared a 
common mechanism of toxicity with other substances had been made at 
that time. (Id. at 55-56). Subsequently, EPA did conclude that 
thiodicarb shares a common mechanism of toxicity with other N-methyl 
carbamate pesticides. (Ref. 8). EPA is re-examining the safety finding 
it made for thiodicarb in light of this conclusion. EPA has completed a 
preliminary cumulative risk assessment for the N-methyl carbamates. EPA 
expects to finish this cumulative risk assessment and make a safety 
determination as to all of the N-methyl carbamates in the near future.

V. The Petition to Modify or Revoke

    The States' petition requests that EPA modify or revoke all of the 
tolerances for alachlor, chlorothalonil, methomyl, metribuzin, and 
thiodicarb. (Ref. 1 at 1). These tolerances must be modified or 
revoked, the States assert, because they do not meet the safety 
standard in section 408 of the FFDCA. (Ref. 1 at 2). The States argue 
that the tolerances are unsafe because EPA's latest safety conclusion 
for these tolerances did not include the full 10X children's safety 
factor and, if that full 10X safety factor is included, EPA cannot make 
the required reasonable certainty of no harm determination.
    The States claim that ``as a matter of law'' the full 10X 
children's safety factor must be retained for each of these pesticides 
because of missing data concerning developmental neurotoxicity, 
endocrine effects, and/or cumulative effects of pesticides having a 
common mechanism of toxicity. It is ``legally impermissible,'' the 
States assert, if any of these data are absent for EPA to conclude that 
there are ``reliable data'' to choose an additional safety factor other 
than 10X. (Ref. 1 at 2, 5, 9, 11). As statutory support for this 
allegation, the States cite several provisions in section 408. First, 
as to developmental neurotoxicity, the States point to section 
408(b)(2)(C)'s requirement that EPA assess the risk to children based 
on ``available information concerning the special susceptibility of 
infants and children to the pesticide chemical residues, including 
neurological differences between infants and children and adults . . . 
.'' The States note that EPA has announced that it plans to require 
developmental neurotoxicity (``DNT'') studies on all pesticides that 
are neurotoxic. (Ref. 1 at 10 citing 64 FR 42945, August 6, 1999). 
Second, as to endocrine effects, the States cite both the provision in 
section 408(b)(2)(D)(vii) requiring consideration of ``such information 
as the Administrator may require on whether the pesticide chemical may 
have an effect in humans that is similar to an effect produced by a 
naturally occurring estrogen or other endocrine effects'' and the 
requirement in section 408(p) for EPA to develop and implement an 
endocrine screening program. Finally, with regard to cumulative 
effects, the States reference the provision in section 408(b)(2)(D)(v) 
requiring consideration of ``available data on the cumulative effects 
of such residues and other substances that have a common mechanism of 
toxicity,'' and the requirement in section 408(b)(2)(C) mandating that 
EPA assess the risk to children based on similar considerations.
    As to the individual pesticides, the States' allegations differ to 
some extent regarding developmental neurotoxicity data and cumulative 
effects data. The States claim that alachlor, methomyl, and thiodicarb 
are ``neurotoxin[s]'' and therefore, under EPA's own criterion, require 
a DNT study. (Ref. 1 at 14, 17, 19). No such claim is made as to 
chlorothalonil or metribuzin. As to cumulative effects, the States 
assert that for alachlor, methomyl, and thiodicarb, EPA has concluded 
that they share a common mechanism of toxicity with other substances, 
yet EPA has not assessed the risk posed by these pesticides' tolerances 
taking into account the cumulative effects from their respective common 
mechanism groups. (Ref. 1 at 13, 16-17, 19). For chlorothalonil, the 
States note that EPA has indicated that it may share a common mechanism 
with other pesticides in the same chemical class and argue that EPA has 
not determined whether in fact there is such a common mechanism. (Ref. 
1 at 15). For metribuzin, the States allege that EPA has not evaluated 
whether it shares a common mechanism with other substances. (Ref. 1 at 
18). As to endocrine effects, the States' claim is the same as to all 
five pesticides - endocrine effects data have not been submitted under 
the endocrine screening program for any of the pesticides.
    Finally, the States present the following risk assessment figures 
for the five pesticides which the States claim would, if the full 10X 
safety factor was incorporated, exceed section 408's safety standard:
     Alachlor - exposure from residues in food equals 33 
percent of the RfD for non-nursing infants, 17 percent for children 1-
6, and 12 percent for children 7-12, (Ref. 1 at 14).
     Chlorothalonil - exposure from residues in food equals 60 
percent of the RfD for non-nursing infants and children 1-6, and 32 
percent of the RfD for the U.S. population, (Ref. 1 at 15-16).
     Methomyl - exposure from residues in food equals 67 
percent of the RfD for non-nursing infants, 62 percent for children 1-
6, and 34.6 percent for the U.S. population, (Ref. 1 at 17).
     Metribuzin - exposure from food equals 62 percent of the 
RfD for non-nursing infants, 75 percent for children 1-6 and 36 percent 
for the U.S. population, (Ref. 1 at 18-19).
     Thiodicarb - exposure from food equals 43 percent of the 
RfD for non-nursing infants, 104 percent of the RfD for children 1-6, 
and 68 percent for the U.S. population, (Ref. 1 at 20).

VI. Public Comment

A. In General

    On March 9, 2005, EPA published a notice in the Federal Register 
announcing receipt of the States' petition to modify or revoke 
tolerances and requesting comments on the petition. (70 FR 11646, March 
9, 2005). The notice included a short summary of the petition and 
referenced readers to EPA's electronic docket for a full copy of the 
petition. A period of 60 days was initially allowed for comment. EPA 
received two requests to extend the comment period. Because EPA could 
not publish notice of an extension prior to expiration of the 60 days, 
EPA reopened the comment period for 30 days on May 16, 2005. The 
comment period closed on June 15, 2005. (See 70 FR 25826, May 16, 
2005). EPA received 13 comments on the petition. These comments are 
summarized below. EPA has not repeated comments in instances where they 
were made by more than one commenter.

B. Individual Comments

    1. CropLife America. CropLife America (``CLA'') is a trade 
association

[[Page 43914]]

representing members of the pesticide industry. CLA provided extensive 
comments on the petition. (Ref. 14). CLA notes that, although the 
petition only concerned five pesticides, if the arguments in the 
petition are accepted it would have a ``far broader impact'' because 
the result would be that EPA would ``almost always [have] to apply the 
tenfold safety factor'' in pesticide tolerance decisions. (Id. at 3). 
CLA contends that routinely applying the 10X safety factor across the 
board would cause ``serious market disruption'' and not allow EPA to 
distinguish between ``conventional'' and reduced-risk pesticides.
    According to CLA, the petitioners' assertion that the FQPA mandates 
an ``automatic'' retention of the 10X children's safety factor whenever 
there is a ``data gap'' is not supported by the statute or legislative 
history. (Id. at 5, 11). CLA points out that the statute does not use 
the term ``data gap'' but instead requires an additional safety factor 
to ``take into account the completeness of the data . . . .'' (Id. at 
13). Moreover, CLA argues the statute gives EPA ``broad discretion'' to 
choose a different factor. Additionally, CLA claims that the statute 
bars application of the 10X factor to a pesticide due to the absence of 
data unless the registrant has first been given an opportunity to 
conduct and submit the study. (Id. at 17). Nonetheless, CLA admits that 
the additional 10X factor ``should be imposed . . . if the already 
available data give substantive reason for concern . . . .'' (Id. at 
19).
    As to data on endocrine effects, CLA notes that section 
408(b)(2)(C) - the provision addressing the protection of infants and 
children - does not even address this issue. (Id. at 11). Further, even 
the general provisions of section 408 only require EPA to consider 
``such information as the Administrator may require'' on endocrine 
effects. CLA concludes that ``[s]ince no data requirements pertaining 
to endocrine effects have been imposed, a data base cannot be said to 
be `incomplete' because such endocrine data have not been generated.'' 
(Id. at 12). On cumulative effects, CLA asserts that the statute 
provides no data requirements; rather, EPA is directed to review 
``available data'' on the issue. Thus, CLA argues that the database 
cannot be incomplete as to cumulative effects. (Id.)
    The legislative history, CLA claims, supports its reading of the 
statute as granting EPA broad discretion in determining whether to 
apply the children's safety factor. CLA references portions of the 
National Research Council's report titled ``Pesticides in the Diets of 
Infants and Children'' and the legislative debate and reports which 
refer to the need for EPA ``consider'' an additional factor, and EPA's 
``discretion'' and ``flexibility'' in choosing the appropriate factor 
to protect children. (Id. at 5-8).
    CLA notes several examples of situations relevant to the current 
petition which demonstrate the wisdom of giving EPA discretion in 
applying the children's safety factor. CLA asserts that where there is 
no evidence that a pesticide causes neurotoxicity or developmental 
effects, the absence of a DNT study is unlikely to raise any concern 
regarding such effects. Additionally, where a cumulative assessment has 
not been performed, CLA argues there could be a number of circumstances 
where an additional 10X factor would be unnecessary because various 
exposure considerations would make any meaningful cumulation of effects 
unlikely. (Id. at 13-14).
    Finally, CLA asserts that the databases for the five pesticides 
challenged in the petition are ``data-rich'' and support EPA's decision 
on the children's safety factor