[Federal Register Volume 78, Number 142 (Wednesday, July 24, 2013)]
[Rules and Regulations]
[Pages 44444-44455]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-17869]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[EPA-HQ-OPP-2012-0628; FRL-9393-2]
Mancozeb; Pesticide Tolerances
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for residues of
mancozeb in or on walnuts and tangerines. United Phosphorus requested
the tolerance for walnuts and Dow AgroSciences requested the tolerance
for tangerines under the Federal Food, Drug, and Cosmetic Act (FFDCA).
DATES: This regulation is effective July 24, 2013. Objections and
requests for hearings must be received on or before September 23, 2013,
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: The docket for this action, identified by docket
identification (ID) number EPA-HQ-OPP-2012-0628, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory
Public Docket (OPP Docket) in the Environmental Protection Agency
Docket Center (EPA/DC), EPA West Bldg., Rm. 3334, 1301 Constitution
Ave. NW., Washington, DC 20460-0001. The Public Reading Room is open
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal
holidays. The telephone number for the Public Reading Room is (202)
566-1744, and the telephone number for the OPP Docket is (703) 305-
5805. Please review the visitor instructions and additional information
about the docket available at http://www.epa.gov/dockets.
FOR FURTHER INFORMATION CONTACT: Lois Rossi, Registration Division
(7505P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; telephone
number: (703) 305-7090; email address: [email protected].
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.
The following list of North American Industrial Classification System
(NAICS) codes is not intended to be exhaustive, but rather provides a
guide to help readers determine whether this document applies to them.
Potentially affected entities may include:
Crop production (NAICS code 111).
Animal production (NAICS code 112).
Food manufacturing (NAICS code 311).
Pesticide manufacturing (NAICS code 32532).
B. How can I get electronic access to other related information?
You may access a frequently updated electronic version of EPA's
tolerance regulations at 40 CFR part 180 through the Government
Printing Office's eCFR site at http://www.ecfr.gov/cgi-bin/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.
C. How can I file an objection or hearing request?
Under FFDCA section 408(g), 21 U.S.C. 346a, 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-
[[Page 44445]]
OPP-2012-0628 in the subject line on the first page of your submission.
All objections and requests for a hearing must be in writing, and must
be received by the Hearing Clerk on or before September 23, 2013.
Addresses for mail and hand delivery of objections and hearing requests
are provided in 40 CFR 178.25(b).
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 (excluding any Confidential Business Information (CBI)) for
inclusion in the public docket. Information not marked confidential
pursuant to 40 CFR part 2 may be disclosed publicly by EPA without
prior notice. Submit the non-CBI copy of your objection or hearing
request, identified by docket ID number EPA-HQ-OPP-2012-0628, by one of
the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the online instructions for submitting comments. Do not submit
electronically any information you consider to be CBI or other
information whose disclosure is restricted by statute.
Mail: OPP Docket, Environmental Protection Agency Docket
Center (EPA/DC), (28221T), 1200 Pennsylvania Ave. NW., Washington, DC
20460-0001.
Hand Delivery: To make special arrangements for hand
delivery or delivery of boxed information, please follow the
instructions at http://www.epa.gov/dockets/contacts.htm.
Additional instructions on commenting or visiting the docket, along
with more information about dockets generally, is available at http://www.epa.gov/dockets.
II. Summary of Petitioned-For Tolerance
In the Federal Register of May 2, 2012 (77 FR 25954) (FRL-9346-1),
EPA issued a document pursuant to FFDCA section 408(d)(3), 21 U.S.C.
346a(d)(3), announcing the filing of a pesticide petition (PP 1F7935)
by United Phosphorus, Inc., 630 Freedom Business Center, King of
Prussia, PA 19406. The petition requested that 40 CFR 180.176 be
amended by establishing tolerances for residues of the fungicide
mancozeb in or on walnuts at 0.75 parts per million (ppm). That
document referenced a summary of the petition prepared by United
Phosphorus, the registrant, which is available in the docket (EPA-HQ-
OPP-2012-0044), http://www.regulations.gov. There were no comments
received in response to the notice of filing.
In the Federal Register of September 28, 2012 (77 FR 59578) (FRL-
9364-6), EPA issued a document pursuant to FFDCA section 408(d)(3), 21
U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP
2E8062) by Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN
46268. The petition requested that 40 CFR 180.176 be amended by
establishing tolerances for residues of the fungicide mancozeb in or on
tangerine at 10 ppm. The proposed tolerance supports imports of
mandarins, tangerines, and clementines. That document referenced a
summary of the petition prepared by Dow AgroSciences, the registrant,
which is available in the docket (EPA-HQ-OPP-2012-0628) http://www.regulations.gov. There were no comments received in response to the
notice of filing.
Based upon review of the data supporting the petition, EPA has
modified the level at which the tolerance is being established for
walnut. The reason for this change is explained in Unit IV.C.
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. . .
.''
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 mancozeb including exposure
resulting from the tolerances established by this action.
Mancozeb is a member of the ethylene bisdithiocarbamate (EBDC)
group of fungicides that also includes the related active ingredient
metiram, the only other registered EBDC. A third EBDC, maneb, is no
longer registered for use. Mancozeb and metiram are metabolized to
ethylenethiourea (ETU) in the body and both degrade to ETU in the
environment. Therefore, EPA has considered the aggregate or combined
risks from food, water and non-occupational exposure resulting from
mancozeb alone and ETU from all sources (i.e., the other EBDC
fungicides) for this action. EPA's assessment of exposures and risks
associated with mancozeb and ETU 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. In addition to evaluating mancozeb, EPA also evaluated the
risks of ETU, a contaminant, metabolite and degradation product of
mancozeb and the other EBDC group of fungicides, which includes the
related active ingredient metiram.
1. Mancozeb. Mancozeb is not acutely toxic via the oral, dermal or
inhalation routes of exposure. Further, mancozeb is not a skin irritant
nor is it a skin sensitizer, although it does cause mild eye
irritation. The findings in multiple studies demonstrate that the
thyroid is a target organ for mancozeb. Thyroid toxicity is manifested
as alternations in thyroid hormones, increased thyroid weight, and
microscopic thyroid lesions (mainly thyroid follicular cell
hyperplasia). These effects are due to the ETU metabolite.
In a subchronic study in the rat, neuropathology was seen
microscopically (injury to peripheral nerves) with associated clinical
signs (abnormal gait and limited use of rear legs) and loss of muscle
mass. Decreased motor activity occurred in the acute neurotoxicity
study. In the developmental neurotoxicity study, there was no maternal
toxicity and pup effects were limited to decreased body weight. Other
toxicity included increases in bilateral retinopathy in the chronic rat
study. Elevated cholesterol and a mild, regenerative, anemia occurred
in subchronic and chronic dog studies.
Mancozeb is rapidly absorbed and eliminated in the urine. In oral
rat metabolism studies with radiolabeled mancozeb and other EBDCs, an
average 7.5% in vivo metabolic conversion of EBDC to ETU occurred, on a
weight-to-
[[Page 44446]]
weight basis. Metabolism data indicate mancozeb does not bio-
accumulate. Mancozeb has been tested in a series of in vitro and in
vivo genotoxicity assays, which have shown that it exhibits weak
genotoxic potential.
Thyroid follicular cell adenomas and carcinomas were increased in
high-dose males and females in the combined rat toxicity/
carcinogenicity study with mancozeb. Doses in a mouse study were too
low to assess carcinogenicity, and there were no treatment-related
changes in tumor rates. Historically, mancozeb's potential for
carcinogenicity has been based on its metabolite ETU, which is
classified as a probable human carcinogen. However, since ETU is known
to be the chemical causing the thyroid tumors observed, the cancer
assessment has been done only for ETU rather than the parent compound.
Developmental defects in the rat developmental toxicity study
included hydrocephaly, skeletal system defects, and other gross defects
which occurred at a dose causing maternal mortality and did not
indicate increased susceptibility of offspring. Abortions occurred in
the rabbit developmental toxicity study at the high dose which also
caused maternal mortality, and there was no indication of enhanced
susceptibility of offspring in the rabbit. There was no evidence of
reproductive toxicity in the 2-generation reproduction study in rats.
There was evidence of sensitivity in the developmental neurotoxicity
study with mancozeb with decreased pup body weight observed in the
absence of maternal toxicity; the selected endpoints are protective for
these pup effects.
An immunotoxicity study has been reviewed and mancozeb did not show
any immunotoxicity potential.
2. ETU. The thyroid is a target organ for ETU; thyroid toxicity in
subchronic and chronic rat, mouse, and dog studies included decreased
levels of thyroxine (T4), increases or decreases in
triiodothyronine (T3), compensatory increases in levels of
thyroid stimulating hormone (TSH), increased thyroid weight, and
microscopic thyroid changes, chiefly hyperplasia. Overt liver toxicity
was observed in one chronic dog study. ETU is classified as a probable
human carcinogen based on liver tumors in female mice.
Developmental defects in the rat developmental study were similar
to those seen with mancozeb, and included hydrocephaly and related
lesions, skeletal system defects, and other gross defects. These
defects showed increased susceptibility to fetuses because they
occurred at a dose which only caused decreased maternal food
consumption and body weight gain.
An immunotoxicity study on ETU did not show any immunotoxicity
potential.
Specific information on the studies received and the nature of the
adverse effects caused by mancozeb 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 http://www.regulations.gov in the document titled ``Mancozeb: Human Health
Risk Assessment to Support Proposed New Section 3 Uses on Walnuts and
Tolerances for Imported Tangerines'' on pages 70-75 in docket ID number
EPA-HQ-OPP-2012-0628.
Additionally, specific information on the studies received and the
nature of the toxic effects caused by ETU as well as the NOAEL and the
LOAEL from the toxicity studies can be found at www.regulations.gov in
the document titled ``Ethylene Thiourea (ETU); Aggregate Human Health
Risk Assessment of the Common Metabolite/Degradate Ethylene Thiourea
(ETU) to Support Proposed New Section 3 Use on Walnuts and Tolerance
for Imported Tangerines'' on pages 30-33 in docket ID number EPA-HQ-
OPP-2012-0628.
B. Toxicological Points of Departure/Levels of Concern
Once a pesticide's toxicological profile is determined, EPA
identifies toxicological points of departure (POD) and levels of
concern to use in evaluating the risk posed by human exposure to the
pesticide. For hazards that have a threshold below which there is no
appreciable risk, the toxicological POD is used as the basis for
derivation of reference values for risk assessment. PODs are developed
based on a careful analysis of the doses in each toxicological study to
determine the dose at which no adverse effects are observed (the NOAEL)
and the lowest dose at which adverse effects of concern are identified
(the LOAEL). Uncertainty/safety factors are used in conjunction with
the POD to calculate a safe exposure level--generally referred to as a
population-adjusted dose (PAD) or a reference dose (RfD)--and a safe
margin of exposure (MOE). For non-threshold risks, the Agency assumes
that any amount of exposure will lead to some degree of risk. Thus, the
Agency estimates risk in terms of the probability of an occurrence of
the adverse effect expected in a lifetime. For more information on the
general principles EPA uses in risk characterization and a complete
description of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
A summary of the toxicological endpoints for mancozeb and ETU used
for human risk assessment is shown in Tables 1 and 2 of this unit.
Table 1--Summary of Toxicological Doses and Endpoints for Mancozeb for Use in Human Health Risk Assessment
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Point of departure Study and
Exposure/scenario and uncertainty/ RfD, PAD, LOC for risk assessment toxicological
safety factors effects
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Acute dietary (Adult Males, NOAEL = 500 mg/kg/ Acute RfD = 5 mg/kg/day........... Acute neurotoxicity
Females > 49, and Children >= 6 day. aPAD = 5 mg/kg/day................ study in the rat.
years). UFA = 10x........... LOAEL 1,000 mg/kg/
UFH = 10x........... day based on
FQPA SF = 1x........ decreased motor
activity.
Acute dietary (Children < 6 NOAEL = 500 mg/kg/ Acute RfD = 5 mg/kg/day........... Acute neurotoxicity
years). day. aPAD = 0.5 mg/kg/day.............. study in the rat.
UFA = 10x........... LOAEL 1,000 mg/kg/
UFH = 10x........... day based on
FQPA SF UFDB = 10x.. decreased motor
activity.
[[Page 44447]]
Acute Dietary (Females 13-49 NOAEL = 1.28 mg/kg/ Acute RfD = 1.3 mg/kg/day......... Developmental
years). day. aPAD = 0.13 mg/kg/day............. toxicity study in
UFA = 10x........... the rat.
UFH = 10x........... LOAEL = 512 mg/kg/
FQPA SF UFDB = 10x.. day based on
hydrocephaly and
other
malformations.
Chronic dietary (Adult Males, NOAEL = 4.83 mg/kg/ Chronic RfD = 0.16 mg/kg/day...... Toxicity/
Females > 49, and Children >= 6 day. cPAD = 0.16 mg/kg/day............. Carcinogenicity in
years). UFA = 3x............ the rat.
UFH = 10x........... LOAEL = 30.9 mg/kg/
FQPA SF = 1x........ day based on
thyroid toxicity.
Chronic dietary (Females 13-49 NOAEL = 4.83 mg/kg/ Chronic RfD = 0.16 mg/kg/day...... Toxicity/
years and Children < 6 years). day. cPAD = 0.016 mg/kg/day............ Carcinogenicity in
UFA = 3x............ the rat.
UFH = 10x........... LOAEL = 30.9 mg/kg/
FQPA SF UFDB = 10x.. day based on
thyroid toxicity.
Inhalation all durations (Adult Inhalation study LOC for MOE = 30.................. Subchronic
Males, Females > 49 years, and NOAEL = 0.079 mg/L Inhalation in the
Children >= 6 years). (21 mg/kg/day). rat.
UFA = 3x............ LOAEL = 0.326 mg/L
UFH = 10x........... based on thyroid
FQPA SF = 1x........ toxicity.
Inhalation all durations (Females Inhalation study LOC for MOE = 300................. Subchronic
13-49 years and Children < 6 NOAEL= 0.079 mg/L Inhalation in the
years). (21 mg/kg/day). rat.
UFA = 3x............ LOAEL = 0.326 mg/L
UFH = 10x........... based on thyroid
FQPA SF UFDB = 10x.. toxicity.
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Cancer (Oral, dermal, inhalation) Mancozeb's potential for carcinogenicity is due to the formation of the
metabolite, ETU, which is classified as a probable human carcinogen.
Mancozeb's cancer risk is calculated by estimating exposure to mancozeb-
derived ETU and using the ETU cancer potency factor (Q1\*\) of 6.01 x 10-2
(mg/kg/day)-1 to quantitate risk.
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FQPA SF = Food Quality Protection Act Safety Factor. LOAEL = lowest-observed-adverse-effect-level. LOC = level
of concern. mg/kg/day = milligrams/kilogram/day. MOE = margin of exposure. NOAEL = no-observed-adverse-effect-
level. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. UF = uncertainty factor.
UFA = extrapolation from animal to human (interspecies). UFDB = to account for the absence of data or other
data deficiency. UFH = potential variation in sensitivity among members of the human population
(intraspecies).
Table 2--Summary of Toxicological Doses and Endpoints for ETU for Use in Human Health Risk Assessment
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Point of departure
Exposure/scenario and uncertainty/ RfD, PAD, LOC for Study and toxicological effects
safety factors risk assessment
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Acute dietary (General population A study with acute
including infants and children). toxicity applicable
to the general
population was not
identified.
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Acute Dietary (Females 13-49 NOAEL = 5 mg/kg/day. Acute RfD = 0.05 mg/ Developmental Rat Toxicity.
years). UFA = 10x........... kg/day. LOAEL = 10 mg/kg/day, based on
UFH = 10x........... aPAD = 0.005 mg/kg/ hydrocephaly and other
FQPA SF UFDB = 10x.. day. malformations.
[[Page 44448]]
Chronic dietary (Adult Males, NOAEL = 0.18 mg/kg/ Chronic RfD = Dog Chronic Oral Toxicity.
Females > 49, and Children >= 6 day. 0.0018 mg/kg/day. LOAEL = 1.99 mg/kg/day based on
years). UFA = 10x........... cPAD = 0.0018 mg/kg/ thyroid toxicity.
UFH = 10x........... day.
FQPA SF = 1x........
Chronic dietary (Females 13-49 NOAEL = 0.18 mg/kg/ Chronic RfD = Dog Chronic Oral Toxicity.
years and Children < 6 years). day. 0.0018 mg/kg/day. LOAEL = 1.99 mg/kg/day based on
UFA = 10x........... cPAD = 0.00018 mg/ thyroid toxicity.
UFH = 10x........... kg/day.
FQPA SF UFDB = 10x..
Dermal short and intermediate- Oral study.......... LOC for MOE = 1,000 4-Week Range-Finding Dog Study.
term (Children < 6 years old). NOAEL = 7 mg/kg/day LOAEL = 34 mg/kg/day based on
(dermal absorption thyroid toxicity.
rate = 26%).
UFA = 10x...........
UFH = 10x...........
FQPA SF = 10x.......
Dermal short and intermediate- Oral study.......... LOC for MOE = 100.. 4-Week Range-Finding Dog Study.
term (Adult Males, Females. NOAEL = 7 mg/kg/day LOAEL = 34 mg/kg/day based on
> 49 years, Children >= 6 years) (dermal absorption thyroid toxicity.
rate = 26%).
UFA = 10x...........
UFH = 10x...........
FQPA SF = 1x........
Dermal short- and intermediate- Oral study.......... LOC for MOE = 1,000 Developmental Rat Toxicity.
term (Females 13-49 years old). NOAEL = 5 mg/kg/day LOAEL = 10 mg/kg/day, based on
(dermal absorption hydrocephaly and other
rate = 26%). malformations.
UFA = 10x...........
UFH = 10x...........
FQPA SF = 10x.......
Inhalation short- and Oral study.......... LOC for MOE = 1,000 4-Week Range-Finding Dog Study.
intermediate-Term (Children < 6 NOAEL = 7 mg/kg/day. LOAEL = 34 mg/kg/day based thyroid
years of age). UFA = 10x........... toxicity.
UFH = 10x...........
FQPA SF UFDB = 10x..
Inhalation short- and Oral study.......... LOC for MOE = 100.. 4-Week Range-Finding Dog Study.
intermediate-term (adult males, NOAEL= 7 mg/kg/day.. LOAEL = 34 mg/kg/day based thyroid
females > 49 years, children >= UFA = 10x........... toxicity.
6 years). UFH = 10x...........
FQPA SF = 1x........
Inhalation short- and Oral study.......... LOC for MOE = 1,000 Developmental Rat Toxicity.
intermediate-term (Females 13-49 NOAEL = 5 mg/kg/day. LOAEL = 10 mg/kg/day, based on
years old). UFA = 10x........... hydrocephaly and other
UFH = 10x........... malformations.
FQPA SF = 10x.......
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Cancer (Oral, dermal, inhalation) ETU is classified as a probable human carcinogen. ETU's cancer potency factor
(Q1\*\) is 6.01 x 10-2 (mg/kg/day)-1.
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FQPA SF = Food Quality Protection Act Safety Factor. LOAEL = lowest-observed-adverse-effect-level. LOC = level
of concern. mg/kg/day = milligrams/kilogram/day. MOE = margin of exposure. NOAEL = no-observed-adverse-effect-
level. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. UF = uncertainty factor.
UFA = extrapolation from animal to human (interspecies). UFDB = to account for the absence of data or other
data deficiency. UFH = potential variation in sensitivity among members of the human population
(intraspecies).
C. Exposure Assessment
1. Dietary exposure from food and feed uses. In evaluating dietary
exposure to mancozeb, EPA considered exposure under the petitioned-for
tolerances as well as all existing mancozeb tolerances in 40 CFR
180.176. In evaluating dietary exposure to ETU, EPA considered exposure
under the petitioned-for tolerances discussed in this document as well
as all existing uses of the EBDC group of fungicides
[[Page 44449]]
(mancozeb and metiram). EPA assessed dietary exposures from mancozeb
and ETU 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. Such effects were identified
for mancozeb and ETU. In estimating acute dietary exposure for both
mancozeb and ETU, EPA used food consumption information from the 2003-
2008 food consumption data from the U.S. Department of Agriculture's
(USDA's) National Health and Nutrition Examination Survey, What We Eat
in America, (NHANES/WWEIA).
a. Mancozeb. The Agency conducted a highly refined, probabilistic
acute dietary assessment incorporating field trial or monitoring data
from the EBDC/ETU Market Basket Survey, percent crop treated (PCT)
information, and processing study results to assess the established
uses of mancozeb. The monitoring data were used for several commodities
(corn, cucumber, onion, pumpkin, potato, squash, starfruit, tomato,
meat, and milk). For evaluation of the proposed new uses and
tolerances, field trial data, processing factors, PCT data based on
section 18 usage for walnuts, and percent imported commodity in
domestic consumption data on tangerines for mancozeb were used to
refine residue estimates. The entire distributions of residue data from
field trials or monitoring data were used to generate residue
distribution files (RDFs) for commodities that are considered to be not
blended or partially blended. For commodities considered to be blended,
the average residues incorporating the likely maximum estimated PCT was
used as a point estimate.
b. ETU. The Agency conducted a highly refined, probabilistic acute
dietary assessment incorporating field trial or monitoring data from
the EBDC/ETU Market Basket Survey, PCT information, and processing
study results to assess exposures to ETU from the established uses of
mancozeb and metiram. The monitoring data were used for several
commodities (corn, cucumber, onion, pumpkin, potato, squash, starfruit,
tomato, meat, and milk). For evaluation of the proposed new uses and
tolerances, field trial data, processing factors, PCT data based on
section 18 usage for walnuts, and percent imported commodity in
domestic consumption data on tangerines for mancozeb were used to
refine residue estimates. The entire distributions of residue data from
field trials or monitoring data were used to generate residue
distribution files (RDFs) for commodities that are considered to be not
blended or partially blended. For commodities considered to be blended,
the average residues incorporating the likely maximum estimated PCT was
used as a point estimate.
ii. Chronic exposure. In conducting the chronic dietary exposure
assessment for both mancozeb and ETU, EPA used food consumption
information from the 2003-2008 food consumption data from the USDA
NHANES/WWEIA.
a. Mancozeb. The chronic dietary exposure and risk assessment for
mancozeb (non-cancer and cancer) incorporated average values based
either on field trial data or monitoring data and average PCT data for
new and existing uses, as well as processing and cooking factors.
Averages of the field trials were used for the walnuts and tangerines,
while field trial and market basket survey data were used for
established uses.
b. ETU. Chronic anticipated residues were calculated using average
values based either on field trial data or monitoring data and average
PCT data or average projected PCT as well as processing and cooking
factors. Averages of the field trials were used for the walnuts and
tangerines, while field trial and market basket survey data were used
for established uses.
iii. Cancer. EPA determines whether quantitative cancer exposure
and risk assessments are appropriate for a food-use pesticide based on
the weight of the evidence from cancer studies and other relevant data.
If quantitative cancer risk assessment is appropriate, cancer risk may
be quantified using a linear or nonlinear approach. If sufficient
information on the carcinogenic mode of action is available, a
threshold or nonlinear approach is used and a cancer RfD is calculated
based on an earlier noncancer key event. If carcinogenic mode of action
data are not available, or if the mode of action data determines a
mutagenic mode of action, a default linear cancer slope factor approach
is utilized.
The cancer risks were aggregated using the food and drinking water
doses for the general population and the food, water and recreational
doses for home gardeners (considered protective of other residential
scenarios). The average daily dose was used for food and water
exposures and the lifetime average daily dose was used for the
recreational exposures. The aggregate doses were multiplied times the
potency factor for ETU, 0.0601 (mg/kg/day) -1 to determine
the cancer risks.
Mancozeb degrades and/or metabolizes to ETU which causes thyroid
tumors; therefore, EPA has historically attributed mancozeb's
carcinogenicity to the formation of ETU, which is classified as a
probable human carcinogen. The Agency has used the cancer potency
factor (Q1*) of 0.0601 (mg/kg/day) -1 for ETU
(based on liver tumors in female mice) for risk assessment. Therefore,
cancer risk from exposure to mancozeb has been calculated by estimating
exposure to mancozeb-derived ETU and using the Q1* for ETU.
The same approach has been taken for the other EBDCs. EPA's estimated
exposure to mancozeb-derived ETU included ETU residues found in food as
well as ETU formed by metabolic conversion on parent mancozeb in the
body (conversion rate of 0.075).
iv. Anticipated residue and percent crop treated (PCT) information.
Section 408(b)(2)(E) of FFDCA authorizes EPA to use available data and
information on the anticipated residue levels of pesticide residues in
food and the actual levels of pesticide residues that have been
measured in food. If EPA relies on such information, EPA must require
pursuant to FFDCA section 408(f)(1) that data be provided 5 years after
the tolerance is established, modified, or left in effect,
demonstrating that the levels in food are not above the levels
anticipated. For the present action, EPA will issue such Data Call-Ins
as are required by FFDCA section 408(b)(2)(E) and authorized under
FFDCA section 408(f)(1). Data will be required to be submitted no later
than 5 years from the date of issuance of these tolerances.
Section 408(b)(2)(F) of FFDCA states that the Agency may use data
on the actual percent of food treated for assessing chronic dietary
risk only if:
Condition a: The data used are reliable and provide a
valid basis to show what percentage of the food derived from such crop
is likely to contain the pesticide residue.
Condition b: The exposure estimate does not underestimate
exposure for any significant subpopulation group.
Condition c: Data are available on pesticide use and food
consumption in a particular area, the exposure estimate does not
understate exposure for the population in such area.
In addition, the Agency must provide for periodic evaluation of any
estimates used. To provide for the periodic evaluation of the estimate
of PCT as required by FFDCA section 408(b)(2)(F), EPA may require
registrants to submit data on PCT.
For mancozeb and ETU derived from mancozeb, the following maximum
PCT
[[Page 44450]]
estimates were used in the acute dietary risk assessment for the
following crops: Apples: 45%; asparagus: 30%; barley: 2.5%;
cantaloupes: 15%; carrots: 2.5%; celery: 2.5%; corn: 2.5%; cranberries:
20%; cucumbers: 50%; grapes: 20%; oats: 1%; onions: 70%; peanuts: 2.5%;
pears: 50%; potatoes: 65%; pumpkins: 15%; rice: 2.5%; spinach: 2.5%;
squash: 30%; sugar beets: 2.5%; sweet corn: 15%; tomatoes: 50%;
watermelons: 50%; and wheat: 2.5%. A percent import value of 99% was
used for banana.
For mancozeb and ETU derived from mancozeb, the following average
PCT estimates were used in the chronic and cancer dietary risk
assessments for the following crops: Apples: 40%; asparagus: 15%;
barley: 1%; cantaloupes: 5%; carrots: 1%; celery: 1%; cherries: 1%;
corn: 1%; cranberries: 20%; cucumbers: 25%; grapes: 10%; oats: 1%;
onions: 60%; peanuts: 2.5%; pears: 40%; potatoes: 55%; pumpkins: 10%;
rice: 1%; spinach: 1%; squash: 20%; sugar beets: 1%; sweet corn: 5%;
tomatoes: 25%; watermelons: 40%; and wheat: 1%. A percent import value
of 99% was used for banana.
As a further refinement, the commodity having the highest PCT
results with livestock feed uses had these values applied to meat and
milk (potato; 65% CT maximum for acute and 55% CT average for chronic).
For ETU derived from metiram, the following maximum PCT estimates
were used in the acute dietary risk assessment: apples: 15%; potatoes:
10%. A 31% imported commodity in domestic consumption was used for wine
grapes.
For ETU derived from metiram, the following average PCT estimates
were used in the chronic and cancer dietary risk assessment: Apples:
10%; potatoes: 5%. A 31% imported commodity in domestic consumption was
used for wine grapes.
In most cases, EPA uses available data from United States
Department of Agriculture/National Agricultural Statistics Service
(USDA/NASS), proprietary market surveys, and the National Pesticide Use
Database for the chemical/crop combination for the most recent 6-7
years. EPA uses an average PCT for chronic dietary risk analysis. The
average PCT figure for each existing use is derived by combining
available public and private market survey data for that use, averaging
across all observations, and rounding to the nearest 5%, except for
those situations in which the average PCT is less than one. In those
cases, 1% is used as the average PCT and 2.5% is used as the maximum
PCT. EPA uses a maximum PCT for acute dietary risk analysis. The
maximum PCT figure is the highest observed maximum value reported
within the recent 6 years of available public and private market survey
data for the existing use and rounded up to the nearest multiple of 5%.
Also, for the acute risk assessment for mancozeb and ETU derived
from mancozeb, the Agency estimated PCT for the following uses for
mancozeb, which were recently approved in 2011: Almond, 25%; broccoli,
6%; cabbage, 47%; cabbage, Chinese, 47%; head lettuce 75%; leaf lettuce
66%; pepper, bell, 48%; pepper, non-bell, 48%. For the chronic risk
assessment for mancozeb and ETU derived from mancozeb, the Agency
estimated PCT as follows: Almond, 18%; broccoli, 5%; cabbage, 42%;
cabbage, Chinese, 42%; head lettuce 67%; leaf lettuce 62%; pepper,
bell, 44%; pepper, non-bell, 44%. Since metiram is not registered for
use on these crops, all potential ETU exposure on these crops will
result from use of mancozeb.
EPA developed these refined PCT values based on a detailed
chemical-specific analysis. EPA has considered all available relevant
information and concludes that it is unlikely that the PCT values for
these uses will be exceeded during the next 5 years. Further discussion
of how these PCT values were derived can be found at
www.regulations.gov in the document titled ``Percent Crop Treated for
new Uses (PCTn) of Mancozeb on Almonds, Broccoli, Cabbage, Pepper,
Pumpkin, and Winder Squash, PC Code: 014504; DP Barcode: 360397;
Lettuce, both head and Other; PC Code: 014504; DP Barcode: 364745, NON
PRIA, Parent DP: 635267; and Percent Crop Treated with Maneb for
Collards, Mustard Greens, Turnip Greens, and Kale'' in docket ID number
EPA-HQ-OPP-2012-0628.
For mancozeb and ETU derived from mancozeb, a maximum PCT projected
estimate of 50% for walnuts and a maximum percent import consumption
value of 35% for tangerines were used in the acute dietary risk
assessment. An average PCT estimate of 40% for walnuts as well as an
average percent imported commodity in domestic consumption value of 29%
for tangerines were used in the chronic and cancer dietary risk
assessments.
The walnut information is an amalgamation of the USDA/NASS and
private pesticide market research data. The PCT values for walnuts are
derived from survey data reported in 2006, 2010, and 2011. Only the
state of California is represented in the survey data as 99% of the
walnuts grown in the United States are grown in that state. The percent
of imported fresh mandarin oranges in domestic consumption was
calculated with data for the reporting period of 2008-2013 obtained
from the Foreign Agricultural Service (FAS) USDA/Office of Global
Analysis (FAS, 2013).
The Agency believes that the three conditions discussed in Unit
III.C.1.iv. have been met. With respect to Condition a, PCT estimates
are derived from Federal and private market survey data, which are
reliable and have a valid basis. The Agency is reasonably certain that
the percentage of the food treated is not likely to be an
underestimation. As to Conditions b and c, regional consumption
information and consumption information for significant subpopulations
is taken into account through EPA's computer-based model for evaluating
the exposure of significant subpopulations including several regional
groups. Use of this consumption information in EPA's risk assessment
process ensures that EPA's exposure estimate does not understate
exposure for any significant subpopulation group and allows the Agency
to be reasonably certain that no regional population is exposed to
residue levels higher than those estimated by the Agency. Other than
the data available through national food consumption surveys, EPA does
not have available reliable information on the regional consumption of
food to which mancozeb may be applied in a particular area.
2. Dietary exposure from drinking water--i. Mancozeb. The Agency
has determined that mancozeb is very short-lived in soil and water, and
would not reach water used for human consumption whether from surface
water or ground water.
ii. ETU. ETU is highly water soluble, and may reach both surface
water and ground water under some conditions. The ETU surface water
Estimated Drinking Water Concentrations (EDWCs) were generated using a
combined monitoring/modeling approach. Results of a surface water
monitoring study conducted by the ETU Task Force were used to refine
the outputs of the Pesticide Root Zone Model/Exposure Analysis Modeling
System (PRZM-EXAMS) models; the site/scenario modeled was application
of an EBDC fungicide on peppers in Florida, and was chosen to produce
the highest EDWC acute values. The ground water EDWC was detected in a
Florida community water system intake in a targeted ground water
monitoring study conducted by the EBDC task force from 1999 to 2003.
Both these surface water and ground water values represent
[[Page 44451]]
upper-bound conservative estimates of the total ETU residual
concentrations that might be found in surface water and ground water
due to the use of the EBDC fungicides.
Based on the PRZM/EXAMS and monitoring studies, the EDWCs of ETU
acute and chronic exposures are estimated to be 25.2 parts per billion
(ppb), and 0.1 ppb, respectively for surface water. The EDWC for acute
and chronic exposure is estimated to be 0.21 ppb for ground water.
Estimates of drinking water concentrations were directly entered
into the dietary exposure model. For acute dietary risk assessment, the
water concentration value of 25.2 ppb was used to assess the
contribution to drinking water. For chronic dietary risk assessment of
ETU, the water concentration of value 0.21 ppb was used to assess the
contribution to drinking water. For cancer dietary risk assessment of
ETU, the water concentration of value 0.21 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).
1. Mancozeb. Mancozeb is currently registered for use on the
following residential sites: Home gardens, golf courses, and sod farms
(where treated sod could be transplanted to a residential setting). The
Agency has determined that it is appropriate to aggregate chronic
exposure through food with short-term residential exposures to
mancozeb.
The exposure scenario that was evaluated for mancozeb was the
residential handler home garden use which considers residential handler
exposures (inhalation) to adult applicators combined with average food
exposures. Dermal exposure was not evaluated because no effects were
observed in a mancozeb 28-day dermal toxicity study.
For post-application, dermal exposure to home gardeners (adults and
youth) harvesting vegetables from treated gardens and golfers (adults
and youth) contacting mancozeb-treated turf after application is
possible. However, as no dermal hazard was identified for mancozeb, a
quantitative dermal post-application assessment (non-cancer/short-term
and cancer) for the dermal exposure to home gardeners and golfers
(adults and youth) was only performed for its metabolite, ETU.
The previous mancozeb risk assessment had evaluated the short/
intermediate-term exposure of toddlers to treated turf from the sod
farm use. In the most recent risk assessment, the Agency considered
post-application exposure resulting from this scenario to be negligible
for the following reasons: (1) Mancozeb has a post-harvest interval
(PHI) of 5 days for sod; (2) it is unlikely that sod treated with
mancozeb would be installed more than once per year; (3) transplanted
sod requires constant and significant watering which will result in
decreased mancozeb residues on the transplanted sod; and (4) it is
unlikely that adults or children will spend any significant amount of
time on recently transplanted sod until it is rooted which typically
occurs around 2 weeks after transplanting. Therefore, dermal and
incidental oral post-application scenarios were not quantitatively
assessed for the sod farm use of mancozeb. There are no post-
application exposure risks of concern anticipated from the use of
mancozeb on sod farms.
ii. ETU. ETU non-dietary exposure is expected as a result of the
registered uses of mancozeb, which is currently registered for use on
the following residential sites: home gardens, golf courses, and sod
farms (where treated sod could be transplanted to a residential
setting). There are no uses of metiram that will result in exposure in
residential settings. The Agency has determined that it is appropriate
to aggregate chronic exposure through food with short-term residential
exposures to ETU.
The scenario that was evaluated for ETU was the residential home
garden use, which considered handler garden exposures (inhalation and
dermal) plus average daily food and drinking water exposure for adults
and post-application garden exposures (dermal) plus average daily food
and drinking water exposure for females 13-49 years old and youths.
The previous risk assessment also considered treated turf (sod
farm) post-application exposures to toddlers (incidental oral and
dermal). This more recent risk assessment did not evaluate the sod farm
use for the reasons outlined above in the mancozeb non-dietary exposure
section.
The previous risk assessment also calculated risks for adult and
youth golfers from golfing on treated turf. The more recent assessment
concluded that for residential post-application, the gardening
scenarios represent the most conservative exposure estimates and are
used in the aggregate assessment. The gardening scenarios result in
higher estimated exposure than the golfing scenarios and are therefore
protective of any golfer risk.
Further information regarding EPA standard assumptions and generic
inputs for residential exposures may be found at http://www.epa.gov/pesticides/trac/science/trac6a05.pdf.
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.''
As previously mentioned, the risk estimates summarized in this
document are those that result only from the use of mancozeb, and ETU
derived from mancozeb and metiram, the other registered EBDC chemical,
both of which are dithiocarbamates. For the purposes of this action,
EPA has concluded that mancozeb does not share a common mechanism of
toxicity with other substances. The Agency reached this conclusion
after a thorough internal review and external peer review of the data
on a potential common mechanism of toxicity.
EPA concluded that the available evidence does not support grouping
the dithiocarbamates based on a common toxic effect (neuropathology)
occurring by a common mechanism of toxicity (related to metabolism to
carbon disulfide). After a thorough internal and external peer review
of the existing data bearing on a common mechanism of toxicity, EPA
concluded that the available evidence shows that neuropathology cannot
be linked with carbon disulfide formation. For more information, please
see the December 19, 2001 memo, ``The Determination of Whether
Dithiocarbamate Pesticides Share a Common Mechanism of Toxicity'' on
the internet at http://www.epa.gov/oppsrrd1/cumulative/dithiocarb.pdf.
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 (SF). In applying
[[Page 44452]]
this provision, EPA either retains the default value of 10X, or uses a
different additional safety factor when reliable data available to EPA
support the choice of a different factor.
2. Prenatal and postnatal sensitivity--i. Mancozeb. In the rat
developmental study, developmental effects were observed in the
presence of severe maternal effects, including maternal mortality and
clinical signs. In the rabbit developmental study, developmental
effects (spontaneous abortions) were observed at the same dose (80 mg/
kg/day) at which maternal effects included mortality and clinical
signs. In the rat reproduction study, no effects were observed in
offspring, while thyroid effects and body weight gain decrements
occurred in adults. There was evidence of sensitivity in the
developmental neurotoxicity study with mancozeb with decreased pup body
weight occurring in the absence of maternal toxicity; risk assessment
endpoints are protective for these pup effects.
ii. ETU. There is evidence of increased susceptibility of fetuses
to ETU. Fetal malformations occurred mainly in rats, although
hydrocephaly and domed head were observed in a rabbit developmental
study with ETU. The malformations in rats occurred throughout the body.
Hydrocephaly occurred in the absence of maternal toxicity after
treatment with a single dose of ETU. There was a steep dose-response
for the malformations in rats. An acceptable reproductive toxicity
study was not available for ETU. As a result, the Agency evaluated the
level of concern for the effects observed when considered in the
context of all available toxicity data. In addition, the Agency
evaluated the database to determine if there were residual
uncertainties after establishing toxicity endpoints and traditional
uncertainty factors to be used in the ETU risk assessment.
3. Conclusion for mancozeb. EPA is retaining the 10X FQPA safety
factor for women of childbearing age and for children less than 6 years
old but has determined that reliable data show the safety of children
greater than 6 years of age would be adequately protected if the FQPA
safety factor were reduced to 1X. That decision is based on the
following findings:
i. The toxicology database for mancozeb is complete, except that it
lacks adequate data on the developing thyroid. Brain development is
very sensitive to perturbations in thyroid hormones and it is possible
that the developmental thyroid study (being conducted with ETU) could
result in lower NOAELs for women of childbearing age (i.e., fetuses)
and for children less than 6 years old. Results from the developmental
thyroid study will not affect endpoints for children over 6 years of
age (for whom the thyroid system is more developed) or adults as
thyroid data for those populations are already available. Therefore,
the FQPA safety factor is reduced to 1X for these populations.
ii. There was some evidence of neurotoxicity for mancozeb as seen
in the acute and subchronic neurotoxicity studies; however, no
neurotoxicity occurred in the DNT. Additionally, there are clear NOAELs
identified for the effects observed in the toxicity studies. The doses
and endpoints selected for risk assessment are protective of all
neurotoxicological effects observed in the database.
iii. As noted above in Unit III.D.2., there was some evidence of
increased susceptibility of rat pups to mancozeb exposure. Aside from
the uncertainty resulting from the lack of adequate thyroid data (for
which EPA is retaining the 10X FQPA safety factor), there are clear
NOAELs for the offspring effects, and regulatory doses were selected to
be protective of these effects.
iv. There are no residual uncertainties identified in the exposure
databases. The acute, chronic, and cancer dietary exposure assessments
were refined and used PCT estimates and monitoring residue values for
several commodities, including some major contributors to the dietary
risk such as milk and corn commodities. Monitoring or modeling data
were used to derive estimated drinking water concentrations. The
drinking water concentrations that were derived from monitoring data
reflect the highest value found in a community well monitoring program.
The drinking water concentrations from modeling used conservative,
health-protective, high-end estimates and are unlikely to be exceeded.
The residential exposure assessment used residential SOPs, which are
based on conservative high-end assumptions such as maximum application
rates and day 0 exposures. Given the overall conservative nature of the
exposure assumptions, the aggregate (food, water, and residential)
exposure and risk estimates presented in this assessment are not
expected to underestimate actual exposure and risk expected based on
the current and proposed use patterns.
4. Conclusion for ETU. EPA is retaining the 10X FQPA safety factor
for women of childbearing age and for children less than 6 years old
but has determined that reliable data show the safety of children 6
years of age or older would be adequately protected if the FQPA safety
factor were reduced to 1X. That decision is based on the following
findings:
i. The toxicology database for ETU is missing a developmental
thyroid study, a reproduction study, and a developmental neurotoxicity
(DNT) study. These data gaps are being addressed by an ongoing extended
one-generation reproductive toxicity study. Because the developing
brain is very sensitive to perturbations in thyroid hormones, it is
possible that these studies could result in lower NOAELs for women of
childbearing age (i.e., fetuses) and for children less than 6 years
old; however, results from the developmental thyroid study will not
affect points of departure for children greater than 6 years of age,
who have a thyroid system similar to adults, adult females greater than
49 years of age (assumed to be beyond typical child-bearing age), or
adult males since thyroid data for those populations are already
available. Additionally, endpoints from the other segments of the
extended one-generation study will not affect these latter populations,
and the FQPA safety factor is being reduced to 1X for these
populations.
ii. Although the ETU studies were inadequate in evaluating signs of
neurotoxicity, there was no evidence of neurotoxicity seen in any study
in the database. In any event, the Agency has determined that the
selected endpoints would be protective of potential neurotoxicity. The
basis for this is that the principal toxic effects occur in the
thyroid; thyroid effects provide the most sensitive endpoint, which the
Agency is regulating on. Although the extended 1-gen study being
performed on ETU is evaluating the potential for effects on the
developing brain, the Agency does not believe that a 10X FQPA safety
factor is necessary to protect children 6 years old or older because:
(1) The weight-of-evidence of the available data indicates that thyroid
effects are the most sensitive effect of this chemical; (2) the Agency
is regulating on the more sensitive thyroid effect; and (3) the Agency
is retaining a 10X FQPA safety factor for the population most likely
affected by the thyroid effects.
iii. As noted in Unit III.D.2., there is evidence of increased
quantitative and qualitative susceptibility following increased in
utero exposure to ETU. The developmental study with the lowest NOAEL
was selected for the acute endpoint for women of childbearing age and
is therefore protective of the developmental malformations. The only
remaining developmental uncertainties are related to effects on the
developing fetus caused by perturbations in the
[[Page 44453]]
still-not-completely-developed thyroid in children younger than 6 years
old. Brain development being very sensitive to perturbations in thyroid
hormones, it is possible that the extended 1-generation reproductive
toxicity test, in which developmental thyroid effects will be
evaluated, will result in lower NOAELs for these populations than are
presently being used to assess risk; therefore, the Agency is retaining
the 10X FQPA safety factor for females 13-49 years of age and for
children less than 6 years of age.
iv. There are no residual uncertainties identified in the EBDC's
(mancozeb or metiram) exposure databases for ETU assessment. The acute,
chronic, and cancer dietary exposure assessments were refined and used
PCT estimates and monitoring residue values for several commodities
including some major contributors to the dietary risk such as milk and
corn commodities. Monitoring or modeling data were used to derive
estimated drinking water concentrations. The drinking water
concentrations that were derived from monitoring data reflect the
highest value found in a community well monitoring program. The
drinking water concentrations from modeling used conservative, health-
protective, high-end estimates and are unlikely to be exceeded. The
residential exposure assessment used residential SOPs, which are based
on conservative high-end assumptions such as maximum application rates
and day 0 exposures. Given the overall conservative nature of the
exposure assumptions, the aggregate (food, water, and residential)
exposure and risk estimates presented in this assessment are not
expected to underestimate actual exposure and risk expected based on
the current and proposed use patterns.
E. Aggregate Risks and Determination of Safety
EPA determines whether acute and chronic dietary pesticide
exposures are safe by comparing aggregate exposure estimates to the
acute PAD (aPAD) and chronic PAD (cPAD). For linear cancer risks, EPA
calculates the lifetime probability of acquiring cancer given the
estimated aggregate exposure. Short-, intermediate-, and chronic-term
risks are evaluated by comparing the estimated aggregate food, water,
and residential exposure to the appropriate PODs to ensure that an
adequate MOE exists.
1. Acute risk. (mancozeb). The mancozeb acute aggregate assessment
considers acute exposure to mancozeb only and not ETU. Further, this
assessment is based on residues of mancozeb in food only since residues
of mancozeb are not expected in drinking water. Using the exposure
assumptions discussed in this unit for acute exposure, the acute
dietary exposure from food to mancozeb will occupy 9.9% of the aPAD for
children 1-2 years old, the population subgroup receiving the greatest
exposure.
2. Acute risk (ETU). Using the exposure assumptions discussed in
this unit for acute exposure, the acute dietary exposure from food and
water to ETU (from mancozeb and metiram) will occupy 60% of the aPAD
for females 13-49 years of age, the only population group of concern.
3. Chronic risk (mancozeb). There are no long-term residential
exposure scenarios for mancozeb and there is not likely to be residues
of mancozeb in drinking water. Therefore, the long-term or chronic
(non-cancer) aggregate risk for mancozeb includes contribution from
food alone. Using the exposure assumptions described in this unit for
chronic exposure, EPA has concluded that chronic exposure to mancozeb
from food will utilize 2.3% of the cPAD for children 1-2 years of age,
the population group receiving the greatest exposure.
4. Chronic risk (ETU). There are no long-term residential exposure
scenarios for ETU; the aggregate chronic risks were calculated using
food and water exposure only. Using the exposure assumptions described
in this unit for chronic exposure, EPA has concluded that chronic
exposure to ETU (from mancozeb and metiram) from food and water will
utilize 58% of the cPAD for children (1 to 2 years old), the population
group receiving the greatest exposure.
5. Short-term risk (mancozeb). Short-term aggregate exposure takes
into account short-term residential exposure plus chronic exposure to
food and water (considered to be a background exposure level).
Mancozeb 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 exposure through food with short-
term residential exposures to mancozeb. The scenario that was evaluated
for mancozeb was the residential handler home garden use. The aggregate
short-term home garden MOEs for adult males and females greater than 49
years old is 99,000 and the MOE for adult females 13-49 years old is
94,000. Because for mancozeb EPA is concerned only with MOEs that are
below 30 (adult males and females greater than 49 years old) and 300
(adult females 13-49 years old), these MOEs do not raise a risk
concern.
6. Short-term risk (ETU). Short-term aggregate exposure takes into
account short-term residential exposure plus chronic exposure to food
and water (considered to be a background exposure level).
Mancozeb is currently registered for uses that could result in
short-term residential exposure to ETU. There are no residential uses
for metiram. The Agency determined that it was appropriate to aggregate
chronic exposure through food with short-term residential exposures to
ETU. The ETU short-term handler home garden aggregate MOE for adult
females 13-49 years old is 27,000 and for adult males (and females
older than 49 years old) is 42,000. The ETU short-term post-application
home garden aggregate MOE for adult females 13-49 years old is 2,600
and for youths 11-16 years old is 3,100. Because for ETU EPA is
concerned only with MOEs that are below 1,000 (adult females 13-49
years old) and 100 (adult males, females >49 years old and youth 11-16
years old), these MOEs do not raise a risk concern.
7. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account intermediate-term residential exposure plus chronic
exposure to food and water (considered to be a background exposure
level).
An intermediate-term adverse effect was identified; however,
mancozeb is not registered for any use patterns that would result in
intermediate-term residential exposure. Intermediate-term risk is
assessed based on intermediate-term residential exposure plus chronic
dietary exposure. Because there is no intermediate-term residential
exposure and chronic dietary exposure has already been assessed under
the appropriately protective cPAD (which is at least as protective as
the POD used to assess intermediate-term risk), no further assessment
of intermediate-term risk is necessary, and EPA relies on the chronic
dietary risk assessment for evaluating intermediate-term risk for
mancozeb.
8. Aggregate cancer risk for U.S. population. As noted earlier in
this document, mancozeb degrades and/or metabolizes to ETU which causes
the same types of thyroid tumors as those seen when animals are dosed
with mancozeb; therefore, EPA has historically attributed mancozeb's
carcinogenicity to the formation of ETU, which is classified as a
probable human carcinogen.
The cancer aggregate risk estimates (home garden handler and post-
application scenarios) for the U.S.
[[Page 44454]]
population are 2 x 10-6 and 3 x 10-6,
respectively.
EPA generally considers cancer risks (expressed as the probability
of an increased cancer case) in the range of 1 in 1 million (or 1 x
10-6) or less to be negligible. The precision which can be
assumed for cancer risk estimates is best described by rounding to the
nearest integral order of magnitude on the logarithmic scale; for
example, risks falling between 3 x 10-7 and 3 x
10-6 are expressed as risks in the range of 10-6.
Considering the precision with which cancer hazard can be estimated,
the conservativeness of low-dose linear extrapolation, and the rounding
procedure described above, cancer risk should generally not be assumed
to exceed the benchmark level of concern of the range of
10-6 until the calculated risk exceeds approximately 3 x
10-6. This is particularly the case where some conservatism
is maintained in the exposure assessment. Although the mancozeb risk
assessment is highly refined, the Agency believes there is some
conservatism for the following reasons: (1) The linear low-dose
extrapolation approach is conservative because it does not take into
account certain human biological processes such as reversibility and
repair; (2) the residential SOPs are based on conservative high-end
assumptions such as maximum application rates and day 0 exposures; and
(3) some food exposures are estimated based on tolerance-level
residues. Accordingly, EPA has concluded the cancer risk for all
existing mancozeb uses and the uses associated with the tolerances
established in this action fall within the range of 1 x 10-6
and are thus negligible.
9. 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 mancozeb and/or ETU residues.
IV. Other Considerations
A. Analytical Enforcement Methodology
Adequate methods are available for the enforcement of tolerances
for the plant commodities which are the subject of this request. The
Pesticide Analytical Method (PAM) Vol. II lists Methods I, II, III, IV,
and A for the determination of dithiocarbamate residues in/on plant
commodities. The Keppel colorimetric method (Method III) is the
preferred method for tolerance enforcement. The Keppel method
determines EBDCs as a group by degradation to CS2. The
analytical methodology for ETU is based on the original method
published by Olney and Yip (JAOAC 54:165-169).
The method may be requested from: Chief, Analytical Chemistry
Branch, Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD
20755-5350; telephone number: (410) 305-2905; email address:
[email protected].
B. International Residue Limits
In making its tolerance decisions, EPA seeks to harmonize U.S.
tolerances with international standards whenever possible, consistent
with U.S. food safety standards and agricultural practices. EPA
considers the international maximum residue limits (MRLs) established
by the Codex Alimentarius Commission (Codex), as required by FFDCA
section 408(b)(4). The Codex Alimentarius is a joint United Nations
Food and Agriculture Organization/World Health Organization food
standards program, and it is recognized as an international food safety
standards-setting organization in trade agreements to which the United
States is a party. EPA may establish a tolerance that is different from
a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain
the reasons for departing from the Codex level.
There is no Codex MRL established for mancozeb on walnuts.
There is a MRL of 10 ppm established by Codex for the use of EBDC
compounds on mandarins which is consistent with the 10 ppm tolerance on
tangerine being established by this document.
C. Revisions to Petitioned-For Tolerances
Based on the evaluation of the residue data, the Agency is modified
the tolerance for walnuts from the proposed level of 0.75 ppm to 0.70
ppm. EPA revised the tolerance levels based on analysis of the residue
field trial data using the Organization for Economic Cooperation and
Development (OECD) tolerance calculation procedures.
V. Conclusion
Therefore, tolerances are established for residues of mancozeb, in
or on walnut at 0.70 ppm and tangerine at 10 ppm.
VI. Statutory and Executive Order Reviews
This final rule establishes tolerances under FFDCA section 408(d)
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 final rule has
been exempted from review under Executive Order 12866, this final rule
is not subject to Executive Order 13211, entitled ``Actions Concerning
Regulations That Significantly Affect Energy Supply, Distribution, or
Use'' (66 FR 28355, May 22, 2001) 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 FFDCA section 408(d), 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 FFDCA section 408(n)(4). 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 9, 2000) do not apply to this final rule. In addition,
this final 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) (2 U.S.C. 1501 et seq.).
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
[[Page 44455]]
Transfer and Advancement Act of 1995 (NTTAA) (15 U.S.C. 272 note).
VII. Congressional Review Act
Pursuant to the Congressional Review Act (5 U.S.C. 801 et seq.),
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
the rule in the Federal Register. This action 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: July 16, 2013.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.
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. In Sec. 180.176, add alphabetically the following commodities and
the footnote to the table in paragraph (a) to read as follows:
Sec. 180.176 Mancozeb; tolerances for residues.
(a) * * *
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
* * * * *
Tangerine\1\................................................ 10
* * * * *
Walnut...................................................... 0.70
* * * * *
------------------------------------------------------------------------
\1\ There are no U.S. registrations for use of mancozeb on tangerine.
* * * * *
[FR Doc. 2013-17869 Filed 7-23-13; 8:45 am]
BILLING CODE 6560-50-P