Dicamba; Pesticide Tolerance, 17914-17918 [E8-6674]
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Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations
[FR Doc. E8–6818 Filed 4–1–08; 8:45 am]
FOR FURTHER INFORMATION CONTACT:
BILLING CODE 6560–50–S
40 CFR Part 180
Susan Stanton, Registration Division
(7505P), Office of Pesticide Programs,
Environmental Protection Agency, 1200
Pennsylvania Ave., NW., Washington,
DC 20460–0001; telephone number:
(703) 305–5218; e-mail address:
stanton.susan@epa.gov.
[EPA–HQ–OPP–2007–0325; FRL–8356–6]
SUPPLEMENTARY INFORMATION:
Dicamba; Pesticide Tolerance
I. General Information
Environmental Protection
Agency (EPA).
ACTION: Final rule.
A. Does this Action Apply to Me?
ENVIRONMENTAL PROTECTION
AGENCY
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AGENCY:
SUMMARY: This regulation establishes
tolerances for combined residues of
dicamba and its 5-hydroxy metabolite in
or on corn, sweet, forage; corn, sweet,
kernel plus cob with husks removed;
and corn, sweet, stover. Interregional
Research Project Number 4 (IR-4)
requested these tolerances under the
Federal Food, Drug, and Cosmetic Act
(FFDCA).
DATES: This regulation is effective April
2, 2008. Objections and requests for
hearings must be received on or before
June 2, 2008, 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–2007–0325. To access the
electronic docket, go to https://
www.regulations.gov, select ‘‘Advanced
Search,’’ then ‘‘Docket Search.’’ Insert
the docket ID number where indicated
and select the ‘‘Submit’’ button. Follow
the instructions on the regulations.gov
website to view the docket index or
access available documents. All
documents in the docket are listed in
the docket index available in
regulations.gov. Although listed in the
index, some information is not publicly
available, e.g., Confidential Business
Information (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
Regulatory Public Docket in Rm. S–
4400, One Potomac Yard (South Bldg.),
2777 S. Crystal Dr., Arlington, VA. The
Docket Facility is open from 8:30 a.m.
to 4 p.m., Monday through Friday,
excluding legal holidays. The Docket
Facility telephone number is (703) 305–
5805.
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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 those engaged in the
following activities:
• Crop production (NAICS code
111), e.g., agricultural workers;
greenhouse, nursery, and floriculture
workers; farmers.
• Animal production (NAICS code
112), e.g., cattle ranchers and farmers,
dairy cattle farmers, livestock farmers.
• Food manufacturing (NAICS code
311), e.g., agricultural workers; farmers;
greenhouse, nursery, and floriculture
workers; ranchers; pesticide applicators.
• Pesticide manufacturing (NAICS
code 32532), e.g., agricultural workers;
commercial applicators; farmers;
greenhouse, nursery, and floriculture
workers; residential users.
This listing is not intended to be
exhaustive, but rather to provide 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. If you have any
questions regarding the applicability of
this action to a particular entity, consult
the person listed under FOR FURTHER
INFORMATION CONTACT.
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 EPA’s tolerance
regulations at 40 CFR part 180 through
the Government Printing Office’s pilot
e-CFR site at https://www.gpoaccess.gov/
ecfr.
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C. Can I File an Objection or Hearing
Request?
Under section 408(g) of FFDCA, any
person may file an objection to any
aspect of this regulation and may also
request a hearing on those objections.
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–2007–0325 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
as required by 40 CFR part 178 on or
before June 2, 2008.
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 this copy,
identified by docket ID number EPA–
HQ–OPP–2007–0325, 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 Bldg.), 2777 S.
Crystal Dr., 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 Facility telephone number is
(703) 305–5805.
II. Petition for Tolerance
In the Federal Register of May 9, 2007
(72 FR 26375) (FRL–8128–1), EPA
issued a notice pursuant to section
408(d)(3) of FFDCA, 21 U.S.C.
346a(d)(3), announcing the filing of a
pesticide petition ((PP) 0E6209) by
Interregional Research Project Number 4
(IR-4), 500 College Road East, Suite 201
W, Princeton, NJ 08540–6635. The
petition requested that 40 CFR 180.227
be amended by establishing tolerances
for combined residues of the herbicide
dicamba, 3,6-dichloro-o-anisic acid, and
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its metabolite, 3,6-dichloro-5-hydroxy-oanisic acid, in or on corn, sweet, forage
at 0.50 parts per million (ppm); corn,
sweet, kernel plus cob with husks
removed at 0.04 ppm; and corn, sweet,
stover at 0.50 ppm. That notice
referenced a summary of the petition
prepared by BASF Corporation, the
registrant, which is available to the
public in the docket, https://
www.regulations.gov. There were no
comments received in response to the
notice of filing.
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III. Aggregate Risk Assessment and
Determination of Safety
Section 408(b)(2)(A)(i) of FFDCA
allows EPA to establish a tolerance (the
legal limit for a pesticide chemical
residue in or on a food) only if EPA
determines that the tolerance is ‘‘safe.’’
Section 408(b)(2)(A)(ii) of 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.’’ This includes
exposure through drinking water and in
residential settings, but does not include
occupational exposure. Section
408(b)(2)(C) of FFDCA requires EPA to
give special consideration to 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....’’ These provisions
were added to FFDCA by the Food
Quality Protection Act (FQPA) of 1996.
Consistent with FFDCA section
408(b)(2)(D), and the factors specified in
FFDCA section 408(b)(2)(D), EPA has
reviewed the available scientific data
and other relevant information in
support of this action. EPA has
sufficient data to assess the hazards of
and to make a determination on
aggregate exposure for the petitioned-for
tolerances for combined residues of
dicamba on corn, sweet, forage at 0.50
ppm; corn, sweet, kernel plus cob with
husks removed at 0.04 ppm; and corn,
sweet, stover at 0.50 ppm. EPA’s
assessment of exposures and risks
associated with establishing the
tolerance follows.
A. Toxicological Profile
EPA has evaluated the available
toxicity data and considered its validity,
completeness, and reliability as well as
the relationship of the results of the
studies to human risk. EPA has also
considered available information
concerning the variability of the
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sensitivities of major identifiable
subgroups of consumers, including
infants and children.
Dicamba has low acute toxicity via
the oral, dermal and inhalation routes.
It is an eye and dermal irritant but it is
not a skin sensitizer. Following oral
administration, dicamba is rapidly
absorbed and excreted in urine and
feces. Consistent neurotoxic signs (e.g.,
ataxia, decreased motor activity,
impaired righting reflex and gait) were
observed in many studies in rats and
rabbits at high doses. Prenatal
developmental toxicity studies in rats
and rabbits showed no evidence
(qualitative or quantitative) of increased
susceptibility following in utero or postnatal exposure to dicamba. There was
an increased incidence of abortion in
the rabbit developmental toxicity study
at doses that also showed maternal
toxicity. In a 2-generation reproduction
study, offspring toxicity was manifested
as decreased pup body weight gain in
all generations at a dose lower than the
parental systemic toxicity NOAEL.
Dicamba is classified as ‘‘Not Likely to
be Carcinogenic to Humans’’ by the oral
route. Mutagenicity studies did not
demonstrate evidence of mutagenic
potential for dicamba although some
positive results were reported in
published literature.
Specific information on the studies
received and the nature of the adverse
effects caused by dicamba as well as the
no-observed-adverse-effect-level
(NOAEL) and the lowest-observedadverse-effect-level (LOAEL) from the
toxicity studies can be found at https://
www.regulations.gov in the document
Dicamba: Human-Health Risk
Assessment for Proposed Section 3 New
Uses on Sweet Corn. The referenced
document is available in the docket
established by this action, which is
described under ADDRESSES, and is
identified as EPA–HQ–OPP–2007–
0325–0004 in that docket.
B. Toxicological Endpoints
For hazards that have a threshold
below which there is no appreciable
risk, the toxicological level of concern
(LOC) is derived from the highest dose
at which no adverse effects are observed
(the NOAEL) in the toxicology study
identified as appropriate for use in risk
assessment. However, if a NOAEL
cannot be determined, the lowest dose
at which adverse effects of concern are
identified (the LOAEL) is sometimes
used for risk assessment. Uncertainty/
safety factors (UFs) are used in
conjunction with the LOC to take into
account uncertainties inherent in the
extrapolation from laboratory animal
data to humans and in the variations in
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sensitivity among members of the
human population as well as other
unknowns. Safety is assessed for acute
and chronic risks by comparing
aggregate exposure to the pesticide to
the acute population adjusted dose
(aPAD) and chronic population adjusted
dose (cPAD). The aPAD and cPAD are
calculated by dividing the LOC by all
applicable UFs. Short-term,
intermediate-term, and long-term risks
are evaluated by comparing aggregate
exposure to the LOC to ensure that the
margin of exposure (MOE) called for by
the product of all applicable UFs is not
exceeded.
For non-threshold risks, the Agency
assumes that any amount of exposure
will lead to some degree of risk and
estimates risk in terms of the probability
of occurrence of additional adverse
cases. Generally, cancer risks are
considered non-threshold. For more
information on the general principles
EPA uses in risk characterization and a
complete description of the risk
assessment process, see https://
www.epa.gov/fedrgstr/EPA-PEST/1997/
November/Day–26/p30948.htm. A
summary of the toxicological endpoints
for dicamba used for human risk
assessment can be found at https://
www.regulations.gov in the document
Dicamba: Human-Health Risk
Assessment for Proposed Section 3 New
Uses on Sweet Corn. The referenced
document is available in the docket
established by this action, which is
described under ADDRESSES, and is
identified as EPA–HQ–OPP–2007–
0325–0004 in that docket.
C. Exposure Assessment
1. Dietary exposure from food and
feed uses. In evaluating dietary
exposure to dicamba, EPA considered
exposure under the petitioned-for
tolerances as well as all existing
dicamba tolerances in 40 CFR 180.227.
EPA assessed dietary exposures from
dicamba in food as follows:
i. Acute exposure. Quantitative acute
dietary exposure and risk assessments
are performed for a food-use pesticide,
if a toxicological study has indicated the
possibility of an effect of concern
occurring as a result of a 1–day or single
exposure. In estimating acute dietary
exposure to dicamba, EPA used food
consumption information from the U.S.
Department of Agriculture (USDA)
1994–1996 and 1998 Nationwide
Continuing Surveys of Food Intake by
Individuals (CSFII). As to residue levels
in food, EPA assumed all foods for
which there are tolerances were treated
and contain tolerance-level residues. No
anticipated residues or percent crop
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treated (PCT) data were used in the
acute dietary exposure assessment.
ii. Chronic exposure. In conducting
the chronic dietary exposure assessment
EPA used the food consumption data
from the USDA 1994–1996 and 1998
CSFII. As to residue levels in food, EPA
assumed all foods for which there are
tolerances were treated and contain
tolerance-level residues. No anticipated
residues or percent crop treated (PCT)
data were used in the chronic dietary
exposure assessment.
iii. Cancer. Based on the results of
carcinogenicity studies in rats and mice,
EPA has concluded that dicamba is ‘‘not
likely to be carcinogenic to humans.’’
Consequently, a quantitative cancer
exposure and risk assessment is not
appropriate for dicamba.
2. Dietary exposure from drinking
water. The residues of concern in
drinking water include dicamba and its
major degradate, DCSA. The Agency
lacks sufficient monitoring data to
complete a comprehensive dietary
exposure analysis and risk assessment
for dicamba and DCSA in drinking
water. Because the Agency does not
have comprehensive monitoring data,
drinking water concentration estimates
are made by reliance on simulation or
modeling taking into account data on
the environmental fate characteristics of
dicamba and DCSA. Further information
regarding EPA drinking water models
used in pesticide exposure assessment
can be found at https://www.epa.gov/
oppefed1/models/water/index.htm.
Based on the Pesticide Root Zone
Model/Exposure Analysis Modeling
System (PRZM/EXAMS) and Screening
Concentration in Ground Water (SCIGROW) models, the combined estimated
environmental concentrations (EECs) of
dicamba and DCSA for acute exposures
are estimated to be 367 parts per billion
(ppb) for surface water and 0.016 ppb
for ground water. The combined EECs
for chronic exposures are estimated to
be 13.8 ppb for surface water and 0.016
ppb for ground water.
Modeled estimates of drinking water
concentrations were directly entered
into the dietary exposure model. For
acute dietary risk assessment, the water
concentration value of 367 ppb was
used to assess the contribution to
drinking water. For chronic dietary risk
assessment, the water concentration of
value 13.8 ppb was used to assess the
contribution to drinking water.
3. From non-dietary exposure. The
term ‘‘residential exposure’’ is used in
this document to refer to nonoccupational, non-dietary exposure
(e.g., for lawn and garden pest control,
indoor pest control, termiticides, and
flea and tick control on pets).
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Dicamba is currently registered for
use on residential sites, including home
lawns and golf courses. EPA assessed
residential exposure using the following
assumptions: Residential handlers are
likely to be exposed to dicamba residues
via dermal and inhalation routes during
handling, mixing, loading and applying
activities. Based on the current use
patterns, EPA expects duration of
handler exposure to be short-term (1–30
days). EPA assessed several residential
handler scenarios and found that
handlers who mix/load and apply
dicamba using a hose-end sprayer have
the highest estimated exposures.
There is also potential for short-term
(1–30 days) post-application exposure of
adults and children/toddlers on lawns
and other turf areas previously treated
with dicamba, as well as the potential
for acute, episodic exposure of toddlers
from ingestion of granules containing
dicamba. EPA assessed short-term
dermal exposure of adults doing
yardwork; short-term dermal and
incidental oral exposure of toddlers
playing on treated turf; and acute
toddler exposure from episodic granule
ingestion. Post-application inhalation
exposures are expected to be negligible
and were, therefore, not assessed.
4. Cumulative effects from substances
with a common mechanism of toxicity.
Section 408(b)(2)(D)(v) of FFDCA
requires that, when considering whether
to establish, modify, or revoke a
tolerance, the Agency consider
‘‘available information’’ concerning the
cumulative effects of a particular
pesticide’s residues and ‘‘other
substances that have a common
mechanism of toxicity.’’
Unlike other pesticides for which EPA
has followed a cumulative risk approach
based on a common mechanism of
toxicity, EPA has not made a common
mechanism of toxicity finding as to
dicamba and any other substances and
dicamba does not appear to produce a
toxic metabolite produced by other
substances. For the purposes of this
tolerance action, therefore, EPA has not
assumed that dicamba has a common
mechanism of toxicity with other
substances. For information regarding
EPA’s efforts to determine which
chemicals have a common mechanism
of toxicity and to evaluate the
cumulative effects of such chemicals,
see EPA’s website at https://
www.epa.gov/pesticides/cumulative.
D. Safety Factor for Infants and
Children
1.In general. Section 408(b)(2)(C) of
FFDCA provides that EPA shall apply
an additional tenfold (‘‘10X’’) margin of
safety for infants and children in the
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case of threshold effects to account for
prenatal and postnatal toxicity and the
completeness of the database on toxicity
and exposure unless EPA determines
based on reliable data that a different
margin of safety will be safe for infants
and children. This additional margin of
safety is commonly referred to as the
FQPA safety factor. In applying this
provision, EPA either retains the default
value of 10X when reliable data do not
support the choice of a different factor,
or, if reliable data are available, EPA
uses a different additional FQPA safety
factor value based on the use of
traditional UFs and/or special FQPA
safety factors, as appropriate.
2. Prenatal and postnatal sensitivity.
The prenatal and postnatal toxicology
database for dicamba includes rat and
rabbit developmental toxicity studies
and a 2–generation reproduction
toxicity study in rats. There was no
evidence (qualitative or quantitative) of
increased susceptibility following in
utero exposure in the developmental
toxicity studies in rats and rabbits.
There was evidence of increased
sensitivity of the offspring following
pre-/postnatal exposure in the 2–
generation reproduction study in rats. In
that study, offspring toxicity was
manifested as decreased pup body
weight in all generations at a dose lower
than the parental systemic toxicity
NOAEL. However, there is low concern
and there are no residual uncertainties
for the increased susceptibility for the
following reasons. The NOAEL of 45
milligrams/kilogram/day (mg/kg)
identified in this study was chosen for
risk assessments for all routes and
exposure durations other than acute oral
exposures. Since this NOAEL is the
lowest (most sensitive endpoint) in the
dicamba toxicity database, and the dose
response observed in the study is well
defined, assuring that this dose is a clear
NOAEL, use of the NOAEL and
endpoint for risk assessment is
protective for all observed toxic effects
of the chemical. The endpoint
(decreased pup body weight) is not
expected to occur as a result of a single
(acute) exposure and was, therefore, not
deemed appropriate for assessing acute
oral exposures.
3. Conclusion. EPA has determined
that reliable data show that it would be
safe for infants and children to reduce
the FQPA safety factor to 3X for acute
oral exposures and to 1X for all other
routes and durations of exposure. That
decision is based on the following
findings:
i. The toxicity database for Dicamba is
complete.
ii. A developmental neurotoxicity
study is not required. Consistent
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neurotoxic signs (e.g., ataxia, decreased
motor activity, impaired righting reflex
and gait) were observed in many studies
in rats and rabbits at high doses. After
considering the available toxicity data,
however, EPA determined that there is
no need for a developmental
neurotoxicity study or additional UFs to
account for neurotoxicity for the
following reasons:
a. Although clinical signs of
neurotoxicity were seen in pregnant
animals, no evidence of developmental
anomalies of the fetal nervous system
were observed in the prenatal
developmental toxicity studies, in either
rats or rabbits, at maternally toxic doses
up to 300 or 400 mg/kg/day,
respectively;
b. There was no evidence of
behavioral or neurological effects on the
offspring in the 2–generation
reproduction study in rats; and
c. The ventricular dilation of the brain
in the combined chronic toxicity and
carcinogenicity study in rats was only
observed in females at the high dose
after two years’ exposure. The
significance of this observation is
questionable, since no similar
histopathological finding was seen in
the subchronic neurotoxicity study.
iii. There is no evidence that dicamba
results in increased susceptibility in in
utero rats or rabbits in the prenatal
developmental toxicity studies.
Although there is quantitative evidence
of increased susceptibility in the 2–
generation reproduction study in rats,
the degree of concern is low, because
there is a well established offspring
toxicity NOAEL in the study and the
risk assessment team did not identify
any residual uncertainties after
establishing toxicity endpoints and
traditional UFs to be used in the risk
assessment of dicamba for all routes and
durations of exposure, except acute oral
exposures.
iv. EPA selected an endpoint from the
acute neurotoxicity study in rats for use
in assessing acute oral exposures. In this
study, neurotoxicity was seen in both
sexes at the lowest dose tested, 300 mg/
kg/day. Since a NOAEL was not
established in the study, EPA has
determined that an FQPA safety factor
of 3X should be used in acute oral risk
assessments for dicamba to account for
uncertainty arising from the use of the
LOAEL instead of a NOAEL. EPA has
reduced the factor from 10X to 3X based
on the following considerations. A
comparison of the acute neurotoxicity
(ACN) study with the rat developmental
toxicity study that showed similar
clinical signs and a NOAEL of 160 mg/
kg/day after 10 days of treatment
indicates that the NOAEL for the acute
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neurotoxicity study is unlikely to be
more than 3– fold lower than the
LOAEL (ACN LOAEL/3 = 100 mg/kg; rat
developmental study NOAEL = 160 mg/
kg). Therefore, it was determined that an
uncertainty factor of 3X for
extrapolation of LOAEL to NOAEL was
adequate.
v. There are no residual uncertainties
identified in the exposure databases.
The dietary food exposure assessments
were performed based on 100%CT and
tolerance-level residues. Conservative
ground water and surface water
modeling estimates were used.
Similarly, conservative assumptions
were used to assess post-application
exposure of children as well as
incidental oral exposure of toddlers.
These assessments will not
underestimate the exposure and risks
posed by dicamba.
E. Aggregate Risks and Determination of
Safety
Safety is assessed for acute and
chronic risks by comparing aggregate
exposure to the pesticide to the aPAD
and cPAD. The aPAD and cPAD are
calculated by dividing the LOC by all
applicable UFs. For linear cancer risks,
EPA calculates the probability of
additional cancer cases given aggregate
exposure. Short-term, intermediateterm, and long-term risks are evaluated
by comparing aggregate exposure to the
LOC to ensure that the MOE called for
by the product of all applicable UFs is
not exceeded.
1. Acute risk. Using the exposure
assumptions discussed in this unit for
acute exposure, the acute dietary
exposure from food and water to
dicamba will occupy 11% of the aPAD
for infants less than 1 year old, the
population with the greatest estimated
exposure. Dicamba is currently
registered for uses that could result in
acute residential exposure of toddlers
from episodic granule ingestion;
however, the Agency has determined
that it is not appropriate to aggregate
acute dietary (food and water) and acute
residential exposures for dicamba, since
it is unlikely that high end dietary
exposure would occur in the same day
as high end oral residential exposure.
High end oral residential exposure is
aggregated with background dietary
exposure in evaluating short-term risk
(see Unit III.E.3.).
2. Chronic risk. Using the exposure
assumptions described in this unit for
chronic exposure, EPA has concluded
that exposure to dicamba from food and
water will utilize 6.7% of the cPAD for
children, 1 to 2 years old, the
population group with the greatest
estimated exposure. Based the use
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pattern, chronic residential exposure to
residues of dicamba is not expected.
3. Short-term risk. Short-term
aggregate exposure takes into account
residential exposure plus chronic
exposure to food and water (considered
to be a background exposure level).
Dicamba is currently registered for uses
that could result in short-term
residential exposure and the Agency has
determined that it is appropriate to
aggregate chronic food and water and
short-term exposures for dicamba.
Using the exposure assumptions
described in this unit for short-term
exposures, EPA has concluded that
food, water, and residential exposures
aggregated result in aggregate MOEs of
1,600 for adults and 1,000 for children.
The MOE for adults takes into
consideration combined residential
handler and postapplication exposures
from doing yardwork on treated turf.
The MOE for children includes
combined postapplication dermal and
incidental oral exposures of toddlers
playing on treated turf.
4. Intermediate-term risk.
Intermediate-term aggregate exposure
takes into account residential exposure
plus chronic exposure to food and water
(considered to be a background
exposure level). Dicamba is not
registered for use on any sites that
would result in intermediate-term
residential exposure. Therefore, the
aggregate risk is the sum of the risk from
food and water, which do not exceed
the Agency’s level of concern.
5. Aggregate cancer risk for U.S.
population. Dicamba has been classified
as ‘‘not likely’’ to be a human
carcinogen and is, therefore, not
expected to pose a cancer risk.
6. Determination of safety. Based on
these risk assessments, EPA concludes
that there is a reasonable certainty that
no harm will result to the general
population, or to infants and children
from aggregate exposure to dicamba
residues.
IV. Other Considerations
A. Analytical Enforcement Methodology
Adequate enforcement methodology
is available to enforce the tolerance
expression. Methods I and II (Gas
Chromotography with Electron Capture
Detection) in the Pesticide Analytical
Manual (PAM) Volume II, are adequate
for the enforcement of tolerances for
residues of dicamba and its metabolite
5-OH dicamba in/on plant commodities
and milk.
B. International Residue Limits
There are no CODEX, Canadian or
Mexican maximum residues limits
E:\FR\FM\02APR1.SGM
02APR1
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Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations
(MRLs) for residues of dicamba on sweet
corn.
mstockstill on PROD1PC66 with RULES
V. Conclusion
Therefore, tolerances are established
for combined residues of dicamba, 3,6dichloro-o-anisic acid, and its
metabolite, 3,6-dichloro-5-hydroxy-oanisic acid, in or on corn, sweet, forage
at 0.50 ppm; corn, sweet, kernel plus
cob with husks removed at 0.04 pm; and
corn, sweet, stover at 0.50 ppm.
VI. Statutory and Executive Order
Reviews
This final rule establishes tolerances
under section 408(d) of FFDCA in
response to a petition submitted to the
Agency. The Office of Management and
Budget (OMB) has exempted these types
of actions from review under Executive
Order 12866, entitled Regulatory
Planning and Review (58 FR 51735,
October 4, 1993). Because this rule has
been exempted from review under
Executive Order 12866, this rule is not
subject to Executive Order 13211,
Actions Concerning Regulations That
Significantly Affect Energy Supply,
Distribution, or Use (66 FR 28355, May
22, 2001) or Executive Order 13045,
entitled Protection of Children from
Environmental Health Risks and Safety
Risks (62 FR 19885, April 23, 1997).
This final rule does not contain any
information collections subject to OMB
approval under the Paperwork
Reduction Act (PRA), 44 U.S.C. 3501 et
seq., nor does it require any special
considerations under Executive Order
12898, entitled Federal Actions to
Address Environmental Justice in
Minority Populations and Low-Income
Populations (59 FR 7629, February 16,
1994).
Since tolerances and exemptions that
are established on the basis of a petition
under section 408(d) of FFDCA, such as
the tolerance in this final rule, do not
require the issuance of a proposed rule,
the requirements of the Regulatory
Flexibility Act (RFA) (5 U.S.C. 601 et
seq.) do not apply.
This final rule directly regulates
growers, food processors, food handlers,
and food retailers, not States or tribes,
nor does this action alter the
relationships or distribution of power
and responsibilities established by
Congress in the preemption provisions
of section 408(n)(4) of FFDCA. As such,
the Agency has determined that this
action will not have a substantial direct
effect on States or tribal governments,
on the relationship between the national
government and the States or tribal
governments, or on the distribution of
power and responsibilities among the
various levels of government or between
VerDate Aug<31>2005
18:23 Apr 01, 2008
Jkt 214001
the Federal Government and Indian
tribes. Thus, the Agency has determined
that Executive Order 13132, entitled
Federalism (64 FR 43255, August 10,
1999) and Executive Order 13175,
entitled Consultation and Coordination
with Indian Tribal Governments (65 FR
67249, November 6, 2000) do not apply
to this rule. In addition, This rule does
not impose any enforceable duty or
contain any unfunded mandate as
described under Title II of the Unfunded
Mandates Reform Act of 1995 (UMRA)
(Public Law 104–4).
This action 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 of 1995
(NTTAA), Public Law 104–113, section
12(d) (15 U.S.C. 272 note).
VII. Congressional Review Act
The Congressional Review Act, 5
U.S.C. 801 et seq., generally provides
that before a rule may take effect, the
agency promulgating the rule must
submit a rule report to each House of
the Congress and to the Comptroller
General of the United States. EPA will
submit a report containing this rule and
other required information to the U.S.
Senate, the U.S. House of
Representatives, and the Comptroller
General of the United States prior to
publication of this final rule in the
Federal Register. This final rule is not
a ‘‘major rule’’ as defined by 5 U.S.C.
804(2).
List of Subjects in 40 CFR Part 180
Environmental protection,
Administrative practice and procedure,
Agricultural commodities, Pesticides
and pests, Reporting and recordkeeping
requirements.
Dated: March 24, 2008.
Daniel C. Kenny,
Acting Director, Registration Division, Office
of Pesticide Programs.
Therefore, 40 CFR chapter I is
amended as follows:
I
PART 180—[AMENDED]
1. The authority citation for part 180
continues to read as follows:
I
Authority: 21 U.S.C. 321(q), 346a and 371.
2. Section 180.227 is amended by
alphabetically adding the following
commodities to the table in paragraph
(a)(1) to read as follows:
I
180.227
PO 00000
Dicamba; tolerances for residues.
(a) General.
(1) * * *
Frm 00038
Fmt 4700
Sfmt 4700
Commodity
Parts per million
*
*
*
*
Corn, sweet, forage ........
Corn, sweet, kernel plus
cob with husks removed .........................
Corn, sweet, stover ........
*
*
*
*
*
*
*
*
*
0.50
0.04
0.50
*
*
[FR Doc. E8–6674 Filed 4–1–08; 8:45 am]
BILLING CODE 6560–50–S
ENVIRONMENTAL PROTECTION
AGENCY
40 CFR Part 180
[EPA–HQ–OPP–2007–0338; FRL–8356–7]
Flonicamid; Pesticide Tolerance
Environmental Protection
Agency (EPA).
ACTION: Final rule.
AGENCY:
SUMMARY: This regulation establishes
tolerances for combined residues of
flonicamid and its metabolites TFNA,
TFNA-AM, and TFNG in or on Brassica,
leafy greens, subgroup 5B; hop, dried
cones; okra; radish, tops; turnip, greens;
vegetable, root, except sugar beet,
subgroup 1B; and vegetable, tuberous
and corm, subgroup 1C. It also increases
established tolerances for combined
residues of flonicamid and its
metabolites TFNA and TFNA-AM in or
on cattle, fat; cattle, meat; egg; goat, fat;
goat, meat; horse, fat; horse, meat; milk;
poultry, fat; poultry, meat; poultry, meat
byproducts; sheep, fat; and sheep, meat.
Interregional Research Project Number 4
(IR–4) requested these tolerances under
the Federal Food, Drug, and Cosmetic
Act (FFDCA). This regulation also
removes existing tolerances for
flonicamid and its metabolites on
mustard greens and potatoes which are
superseded by the new tolerances on
‘‘Brassica, leafy greens, subgroup 5B’’
and ‘‘vegetable, tuberous and corm,
subgroup 1C,’’ respectively.
DATES: This regulation is effective April
2, 2008. Objections and requests for
hearings must be received on or before
June 2, 2008, 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–2007–0338. To access the
electronic docket, go to https://
www.regulations.gov, select ‘‘Advanced
Search,’’ then ‘‘Docket Search.’’ Insert
E:\FR\FM\02APR1.SGM
02APR1
Agencies
[Federal Register Volume 73, Number 64 (Wednesday, April 2, 2008)]
[Rules and Regulations]
[Pages 17914-17918]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-6674]
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[EPA-HQ-OPP-2007-0325; FRL-8356-6]
Dicamba; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This regulation establishes tolerances for combined residues
of dicamba and its 5-hydroxy metabolite in or on corn, sweet, forage;
corn, sweet, kernel plus cob with husks removed; and corn, sweet,
stover. Interregional Research Project Number 4 (IR-4) requested these
tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
DATES: This regulation is effective April 2, 2008. Objections and
requests for hearings must be received on or before June 2, 2008, 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-2007-0325. To access the
electronic docket, go to https://www.regulations.gov, select ``Advanced
Search,'' then ``Docket Search.'' Insert the docket ID number where
indicated and select the ``Submit'' button. Follow the instructions on
the regulations.gov website to view the docket index or access
available documents. All documents in the docket are listed in the
docket index available in regulations.gov. Although listed in the
index, some information is not publicly available, e.g., Confidential
Business Information (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 Regulatory Public Docket in
Rm. S-4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr.,
Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m.,
Monday through Friday, excluding legal holidays. The Docket Facility
telephone number is (703) 305-5805.
FOR FURTHER INFORMATION CONTACT: Susan Stanton, Registration Division
(7505P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-5218; e-mail address: stanton.susan@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 those
engaged in the following activities:
Crop production (NAICS code 111), e.g., agricultural
workers; greenhouse, nursery, and floriculture workers; farmers.
Animal production (NAICS code 112), e.g., cattle ranchers
and farmers, dairy cattle farmers, livestock farmers.
Food manufacturing (NAICS code 311), e.g., agricultural
workers; farmers; greenhouse, nursery, and floriculture workers;
ranchers; pesticide applicators.
Pesticide manufacturing (NAICS code 32532), e.g.,
agricultural workers; commercial applicators; farmers; greenhouse,
nursery, and floriculture workers; residential users.
This listing is not intended to be exhaustive, but rather to
provide 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. If you
have any questions regarding the applicability of this action to a
particular entity, consult the person listed under FOR FURTHER
INFORMATION CONTACT.
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 EPA's tolerance regulations at
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 FFDCA, any person may file an objection to
any aspect of this regulation and may also request a hearing on those
objections. 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-2007-0325 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 as required by 40 CFR part 178 on or
before June 2, 2008.
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 this copy, identified by docket ID number
EPA-HQ-OPP-2007-0325, 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
Bldg.), 2777 S. Crystal Dr., 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 Facility telephone number is (703) 305-5805.
II. Petition for Tolerance
In the Federal Register of May 9, 2007 (72 FR 26375) (FRL-8128-1),
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C.
346a(d)(3), announcing the filing of a pesticide petition ((PP) 0E6209)
by Interregional Research Project Number 4 (IR-4), 500 College Road
East, Suite 201 W, Princeton, NJ 08540-6635. The petition requested
that 40 CFR 180.227 be amended by establishing tolerances for combined
residues of the herbicide dicamba, 3,6-dichloro-o-anisic acid, and
[[Page 17915]]
its metabolite, 3,6-dichloro-5-hydroxy-o-anisic acid, in or on corn,
sweet, forage at 0.50 parts per million (ppm); corn, sweet, kernel plus
cob with husks removed at 0.04 ppm; and corn, sweet, stover at 0.50
ppm. That notice referenced a summary of the petition prepared by BASF
Corporation, the registrant, which is available to the public in the
docket, https://www.regulations.gov. There were no comments received in
response to the notice of filing.
III. Aggregate Risk Assessment and Determination of Safety
Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) of 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.'' This includes exposure through drinking water and in
residential settings, but does not include occupational exposure.
Section 408(b)(2)(C) of FFDCA requires EPA to give special
consideration to 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....'' These provisions were added to FFDCA by the Food Quality
Protection Act (FQPA) of 1996.
Consistent with FFDCA section 408(b)(2)(D), and the factors
specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available
scientific data and other relevant information in support of this
action. EPA has sufficient data to assess the hazards of and to make a
determination on aggregate exposure for the petitioned-for tolerances
for combined residues of dicamba on corn, sweet, forage at 0.50 ppm;
corn, sweet, kernel plus cob with husks removed at 0.04 ppm; and corn,
sweet, stover at 0.50 ppm. EPA's assessment of exposures and risks
associated with establishing the tolerance follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children.
Dicamba has low acute toxicity via the oral, dermal and inhalation
routes. It is an eye and dermal irritant but it is not a skin
sensitizer. Following oral administration, dicamba is rapidly absorbed
and excreted in urine and feces. Consistent neurotoxic signs (e.g.,
ataxia, decreased motor activity, impaired righting reflex and gait)
were observed in many studies in rats and rabbits at high doses.
Prenatal developmental toxicity studies in rats and rabbits showed no
evidence (qualitative or quantitative) of increased susceptibility
following in utero or post-natal exposure to dicamba. There was an
increased incidence of abortion in the rabbit developmental toxicity
study at doses that also showed maternal toxicity. In a 2-generation
reproduction study, offspring toxicity was manifested as decreased pup
body weight gain in all generations at a dose lower than the parental
systemic toxicity NOAEL. Dicamba is classified as ``Not Likely to be
Carcinogenic to Humans'' by the oral route. Mutagenicity studies did
not demonstrate evidence of mutagenic potential for dicamba although
some positive results were reported in published literature.
Specific information on the studies received and the nature of the
adverse effects caused by dicamba as well as the no-observed-adverse-
effect-level (NOAEL) and the lowest-observed-adverse-effect-level
(LOAEL) from the toxicity studies can be found at https://
www.regulations.gov in the document Dicamba: Human-Health Risk
Assessment for Proposed Section 3 New Uses on Sweet Corn. The
referenced document is available in the docket established by this
action, which is described under ADDRESSES, and is identified as EPA-
HQ-OPP-2007-0325-0004 in that docket.
B. Toxicological Endpoints
For hazards that have a threshold below which there is no
appreciable risk, the toxicological level of concern (LOC) is derived
from the highest dose at which no adverse effects are observed (the
NOAEL) in the toxicology study identified as appropriate for use in
risk assessment. However, if a NOAEL cannot be determined, the lowest
dose at which adverse effects of concern are identified (the LOAEL) is
sometimes used for risk assessment. Uncertainty/safety factors (UFs)
are used in conjunction with the LOC to take into account uncertainties
inherent in the extrapolation from laboratory animal data to humans and
in the variations in sensitivity among members of the human population
as well as other unknowns. Safety is assessed for acute and chronic
risks by comparing aggregate exposure to the pesticide to the acute
population adjusted dose (aPAD) and chronic population adjusted dose
(cPAD). The aPAD and cPAD are calculated by dividing the LOC by all
applicable UFs. Short-term, intermediate-term, and long-term risks are
evaluated by comparing aggregate exposure to the LOC to ensure that the
margin of exposure (MOE) called for by the product of all applicable
UFs is not exceeded.
For non-threshold risks, the Agency assumes that any amount of
exposure will lead to some degree of risk and estimates risk in terms
of the probability of occurrence of additional adverse cases.
Generally, cancer risks are considered non-threshold. For more
information on the general principles EPA uses in risk characterization
and a complete description of the risk assessment process, see https://
www.epa.gov/fedrgstr/EPA-PEST/1997/November/Day-26/p30948.htm. A
summary of the toxicological endpoints for dicamba used for human risk
assessment can be found at https://www.regulations.gov in the document
Dicamba: Human-Health Risk Assessment for Proposed Section 3 New Uses
on Sweet Corn. The referenced document is available in the docket
established by this action, which is described under ADDRESSES, and is
identified as EPA-HQ-OPP-2007-0325-0004 in that docket.
C. Exposure Assessment
1. Dietary exposure from food and feed uses. In evaluating dietary
exposure to dicamba, EPA considered exposure under the petitioned-for
tolerances as well as all existing dicamba tolerances in 40 CFR
180.227. EPA assessed dietary exposures from dicamba in food as
follows:
i. Acute exposure. Quantitative acute dietary exposure and risk
assessments are performed for a food-use pesticide, if a toxicological
study has indicated the possibility of an effect of concern occurring
as a result of a 1-day or single exposure. In estimating acute dietary
exposure to dicamba, EPA used food consumption information from the
U.S. Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide
Continuing Surveys of Food Intake by Individuals (CSFII). As to residue
levels in food, EPA assumed all foods for which there are tolerances
were treated and contain tolerance-level residues. No anticipated
residues or percent crop
[[Page 17916]]
treated (PCT) data were used in the acute dietary exposure assessment.
ii. Chronic exposure. In conducting the chronic dietary exposure
assessment EPA used the food consumption data from the USDA 1994-1996
and 1998 CSFII. As to residue levels in food, EPA assumed all foods for
which there are tolerances were treated and contain tolerance-level
residues. No anticipated residues or percent crop treated (PCT) data
were used in the chronic dietary exposure assessment.
iii. Cancer. Based on the results of carcinogenicity studies in
rats and mice, EPA has concluded that dicamba is ``not likely to be
carcinogenic to humans.'' Consequently, a quantitative cancer exposure
and risk assessment is not appropriate for dicamba.
2. Dietary exposure from drinking water. The residues of concern in
drinking water include dicamba and its major degradate, DCSA. The
Agency lacks sufficient monitoring data to complete a comprehensive
dietary exposure analysis and risk assessment for dicamba and DCSA in
drinking water. Because the Agency does not have comprehensive
monitoring data, drinking water concentration estimates are made by
reliance on simulation or modeling taking into account data on the
environmental fate characteristics of dicamba and DCSA. Further
information regarding EPA drinking water models used in pesticide
exposure assessment can be found at https://www.epa.gov/oppefed1/models/
water/index.htm.
Based on the Pesticide Root Zone Model/Exposure Analysis Modeling
System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCI-
GROW) models, the combined estimated environmental concentrations
(EECs) of dicamba and DCSA for acute exposures are estimated to be 367
parts per billion (ppb) for surface water and 0.016 ppb for ground
water. The combined EECs for chronic exposures are estimated to be 13.8
ppb for surface water and 0.016 ppb for ground water.
Modeled estimates of drinking water concentrations were directly
entered into the dietary exposure model. For acute dietary risk
assessment, the water concentration value of 367 ppb was used to assess
the contribution to drinking water. For chronic dietary risk
assessment, the water concentration of value 13.8 ppb was used to
assess the contribution to drinking water.
3. From non-dietary exposure. The term ``residential exposure'' is
used in this document to refer to non-occupational, non-dietary
exposure (e.g., for lawn and garden pest control, indoor pest control,
termiticides, and flea and tick control on pets).
Dicamba is currently registered for use on residential sites,
including home lawns and golf courses. EPA assessed residential
exposure using the following assumptions: Residential handlers are
likely to be exposed to dicamba residues via dermal and inhalation
routes during handling, mixing, loading and applying activities. Based
on the current use patterns, EPA expects duration of handler exposure
to be short-term (1-30 days). EPA assessed several residential handler
scenarios and found that handlers who mix/load and apply dicamba using
a hose-end sprayer have the highest estimated exposures.
There is also potential for short-term (1-30 days) post-application
exposure of adults and children/toddlers on lawns and other turf areas
previously treated with dicamba, as well as the potential for acute,
episodic exposure of toddlers from ingestion of granules containing
dicamba. EPA assessed short-term dermal exposure of adults doing
yardwork; short-term dermal and incidental oral exposure of toddlers
playing on treated turf; and acute toddler exposure from episodic
granule ingestion. Post-application inhalation exposures are expected
to be negligible and were, therefore, not assessed.
4. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when
considering whether to establish, modify, or revoke a tolerance, the
Agency consider ``available information'' concerning the cumulative
effects of a particular pesticide's residues and ``other substances
that have a common mechanism of toxicity.''
Unlike other pesticides for which EPA has followed a cumulative
risk approach based on a common mechanism of toxicity, EPA has not made
a common mechanism of toxicity finding as to dicamba and any other
substances and dicamba does not appear to produce a toxic metabolite
produced by other substances. For the purposes of this tolerance
action, therefore, EPA has not assumed that dicamba has a common
mechanism of toxicity with other substances. For information regarding
EPA's efforts to determine which chemicals have a common mechanism of
toxicity and to evaluate the cumulative effects of such chemicals, see
EPA's website at https://www.epa.gov/pesticides/cumulative.
D. Safety Factor for Infants and Children
1.In general. Section 408(b)(2)(C) of FFDCA provides that EPA shall
apply an additional tenfold (``10X'') margin of safety for infants and
children in the case of threshold effects to account for prenatal and
postnatal toxicity and the completeness of the database on toxicity and
exposure unless EPA determines based on reliable data that a different
margin of safety will be safe for infants and children. This additional
margin of safety is commonly referred to as the FQPA safety factor. In
applying this provision, EPA either retains the default value of 10X
when reliable data do not support the choice of a different factor, or,
if reliable data are available, EPA uses a different additional FQPA
safety factor value based on the use of traditional UFs and/or special
FQPA safety factors, as appropriate.
2. Prenatal and postnatal sensitivity. The prenatal and postnatal
toxicology database for dicamba includes rat and rabbit developmental
toxicity studies and a 2-generation reproduction toxicity study in
rats. There was no evidence (qualitative or quantitative) of increased
susceptibility following in utero exposure in the developmental
toxicity studies in rats and rabbits. There was evidence of increased
sensitivity of the offspring following pre-/postnatal exposure in the
2-generation reproduction study in rats. In that study, offspring
toxicity was manifested as decreased pup body weight in all generations
at a dose lower than the parental systemic toxicity NOAEL. However,
there is low concern and there are no residual uncertainties for the
increased susceptibility for the following reasons. The NOAEL of 45
milligrams/kilogram/day (mg/kg) identified in this study was chosen for
risk assessments for all routes and exposure durations other than acute
oral exposures. Since this NOAEL is the lowest (most sensitive
endpoint) in the dicamba toxicity database, and the dose response
observed in the study is well defined, assuring that this dose is a
clear NOAEL, use of the NOAEL and endpoint for risk assessment is
protective for all observed toxic effects of the chemical. The endpoint
(decreased pup body weight) is not expected to occur as a result of a
single (acute) exposure and was, therefore, not deemed appropriate for
assessing acute oral exposures.
3. Conclusion. EPA has determined that reliable data show that it
would be safe for infants and children to reduce the FQPA safety factor
to 3X for acute oral exposures and to 1X for all other routes and
durations of exposure. That decision is based on the following
findings:
i. The toxicity database for Dicamba is complete.
ii. A developmental neurotoxicity study is not required. Consistent
[[Page 17917]]
neurotoxic signs (e.g., ataxia, decreased motor activity, impaired
righting reflex and gait) were observed in many studies in rats and
rabbits at high doses. After considering the available toxicity data,
however, EPA determined that there is no need for a developmental
neurotoxicity study or additional UFs to account for neurotoxicity for
the following reasons:
a. Although clinical signs of neurotoxicity were seen in pregnant
animals, no evidence of developmental anomalies of the fetal nervous
system were observed in the prenatal developmental toxicity studies, in
either rats or rabbits, at maternally toxic doses up to 300 or 400 mg/
kg/day, respectively;
b. There was no evidence of behavioral or neurological effects on
the offspring in the 2-generation reproduction study in rats; and
c. The ventricular dilation of the brain in the combined chronic
toxicity and carcinogenicity study in rats was only observed in females
at the high dose after two years' exposure. The significance of this
observation is questionable, since no similar histopathological finding
was seen in the subchronic neurotoxicity study.
iii. There is no evidence that dicamba results in increased
susceptibility in in utero rats or rabbits in the prenatal
developmental toxicity studies. Although there is quantitative evidence
of increased susceptibility in the 2-generation reproduction study in
rats, the degree of concern is low, because there is a well established
offspring toxicity NOAEL in the study and the risk assessment team did
not identify any residual uncertainties after establishing toxicity
endpoints and traditional UFs to be used in the risk assessment of
dicamba for all routes and durations of exposure, except acute oral
exposures.
iv. EPA selected an endpoint from the acute neurotoxicity study in
rats for use in assessing acute oral exposures. In this study,
neurotoxicity was seen in both sexes at the lowest dose tested, 300 mg/
kg/day. Since a NOAEL was not established in the study, EPA has
determined that an FQPA safety factor of 3X should be used in acute
oral risk assessments for dicamba to account for uncertainty arising
from the use of the LOAEL instead of a NOAEL. EPA has reduced the
factor from 10X to 3X based on the following considerations. A
comparison of the acute neurotoxicity (ACN) study with the rat
developmental toxicity study that showed similar clinical signs and a
NOAEL of 160 mg/kg/day after 10 days of treatment indicates that the
NOAEL for the acute neurotoxicity study is unlikely to be more than 3-
fold lower than the LOAEL (ACN LOAEL/3 = 100 mg/kg; rat developmental
study NOAEL = 160 mg/kg). Therefore, it was determined that an
uncertainty factor of 3X for extrapolation of LOAEL to NOAEL was
adequate.
v. There are no residual uncertainties identified in the exposure
databases. The dietary food exposure assessments were performed based
on 100%CT and tolerance-level residues. Conservative ground water and
surface water modeling estimates were used. Similarly, conservative
assumptions were used to assess post-application exposure of children
as well as incidental oral exposure of toddlers. These assessments will
not underestimate the exposure and risks posed by dicamba.
E. Aggregate Risks and Determination of Safety
Safety is assessed for acute and chronic risks by comparing
aggregate exposure to the pesticide to the aPAD and cPAD. The aPAD and
cPAD are calculated by dividing the LOC by all applicable UFs. For
linear cancer risks, EPA calculates the probability of additional
cancer cases given aggregate exposure. Short-term, intermediate-term,
and long-term risks are evaluated by comparing aggregate exposure to
the LOC to ensure that the MOE called for by the product of all
applicable UFs is not exceeded.
1. Acute risk. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food and water
to dicamba will occupy 11% of the aPAD for infants less than 1 year
old, the population with the greatest estimated exposure. Dicamba is
currently registered for uses that could result in acute residential
exposure of toddlers from episodic granule ingestion; however, the
Agency has determined that it is not appropriate to aggregate acute
dietary (food and water) and acute residential exposures for dicamba,
since it is unlikely that high end dietary exposure would occur in the
same day as high end oral residential exposure. High end oral
residential exposure is aggregated with background dietary exposure in
evaluating short-term risk (see Unit III.E.3.).
2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to dicamba
from food and water will utilize 6.7% of the cPAD for children, 1 to 2
years old, the population group with the greatest estimated exposure.
Based the use pattern, chronic residential exposure to residues of
dicamba is not expected.
3. Short-term risk. Short-term aggregate exposure takes into
account residential exposure plus chronic exposure to food and water
(considered to be a background exposure level). Dicamba is currently
registered for uses that could result in short-term residential
exposure and the Agency has determined that it is appropriate to
aggregate chronic food and water and short-term exposures for dicamba.
Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded that food, water, and residential
exposures aggregated result in aggregate MOEs of 1,600 for adults and
1,000 for children. The MOE for adults takes into consideration
combined residential handler and postapplication exposures from doing
yardwork on treated turf. The MOE for children includes combined
postapplication dermal and incidental oral exposures of toddlers
playing on treated turf.
4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account residential exposure plus chronic exposure to food
and water (considered to be a background exposure level). Dicamba is
not registered for use on any sites that would result in intermediate-
term residential exposure. Therefore, the aggregate risk is the sum of
the risk from food and water, which do not exceed the Agency's level of
concern.
5. Aggregate cancer risk for U.S. population. Dicamba has been
classified as ``not likely'' to be a human carcinogen and is,
therefore, not expected to pose a cancer risk.
6. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to the general population, or to infants and children from aggregate
exposure to dicamba residues.
IV. Other Considerations
A. Analytical Enforcement Methodology
Adequate enforcement methodology is available to enforce the
tolerance expression. Methods I and II (Gas Chromotography with
Electron Capture Detection) in the Pesticide Analytical Manual (PAM)
Volume II, are adequate for the enforcement of tolerances for residues
of dicamba and its metabolite 5-OH dicamba in/on plant commodities and
milk.
B. International Residue Limits
There are no CODEX, Canadian or Mexican maximum residues limits
[[Page 17918]]
(MRLs) for residues of dicamba on sweet corn.
V. Conclusion
Therefore, tolerances are established for combined residues of
dicamba, 3,6-dichloro-o-anisic acid, and its metabolite, 3,6-dichloro-
5-hydroxy-o-anisic acid, in or on corn, sweet, forage at 0.50 ppm;
corn, sweet, kernel plus cob with husks removed at 0.04 pm; and corn,
sweet, stover at 0.50 ppm.
VI. Statutory and Executive Order Reviews
This final rule establishes tolerances under section 408(d) of
FFDCA in response to a petition submitted to the Agency. The Office of
Management and Budget (OMB) has exempted these types of actions from
review under Executive Order 12866, entitled Regulatory Planning and
Review (58 FR 51735, October 4, 1993). Because this rule has been
exempted from review under Executive Order 12866, this rule is not
subject to Executive Order 13211, Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355,
May 22, 2001) or Executive Order 13045, entitled Protection of Children
from Environmental Health Risks and Safety Risks (62 FR 19885, April
23, 1997). This final rule does not contain any information collections
subject to OMB approval under the Paperwork Reduction Act (PRA), 44
U.S.C. 3501 et seq., nor does it require any special considerations
under Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994).
Since tolerances and exemptions that are established on the basis
of a petition under section 408(d) of FFDCA, such as the tolerance in
this final rule, do not require the issuance of a proposed rule, the
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et
seq.) do not apply.
This final rule directly regulates growers, food processors, food
handlers, and food retailers, not States or tribes, nor does this
action alter the relationships or distribution of power and
responsibilities established by Congress in the preemption provisions
of section 408(n)(4) of FFDCA. As such, the Agency has determined that
this action will not have a substantial direct effect on States or
tribal governments, on the relationship between the national government
and the States or tribal governments, or on the distribution of power
and responsibilities among the various levels of government or between
the Federal Government and Indian tribes. Thus, the Agency has
determined that Executive Order 13132, entitled Federalism (64 FR
43255, August 10, 1999) and Executive Order 13175, entitled
Consultation and Coordination with Indian Tribal Governments (65 FR
67249, November 6, 2000) do not apply to this rule. In addition, This
rule does not impose any enforceable duty or contain any unfunded
mandate as described under Title II of the Unfunded Mandates Reform Act
of 1995 (UMRA) (Public Law 104-4).
This action 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 of 1995 (NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272
note).
VII. Congressional Review Act
The Congressional Review Act, 5 U.S.C. 801 et seq., generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report to each House of the Congress and to
the Comptroller General of the United States. EPA will submit a report
containing this rule and other required information to the U.S. Senate,
the U.S. House of Representatives, and the Comptroller General of the
United States prior to publication of this final rule in the Federal
Register. This final rule is not a ``major rule'' as defined by 5
U.S.C. 804(2).
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: March 24, 2008.
Daniel C. Kenny,
Acting Director, Registration Division, Office of Pesticide Programs.
0
Therefore, 40 CFR chapter I is amended as follows:
PART 180--[AMENDED]
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. Section 180.227 is amended by alphabetically adding the following
commodities to the table in paragraph (a)(1) to read as follows:
180.227 Dicamba; tolerances for residues.
(a) General.
(1) * * *
------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
* * * * *
Corn, sweet, forage.................................. 0.50
Corn, sweet, kernel plus cob with husks removed...... 0.04
Corn, sweet, stover.................................. 0.50
* * * * *
------------------------------------------------------------------------
* * * * *
[FR Doc. E8-6674 Filed 4-1-08; 8:45 am]
BILLING CODE 6560-50-S