[Federal Register Volume 63, Number 197 (Tuesday, October 13, 1998)]
[Rules and Regulations]
[Pages 54587-54594]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-27396]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300740; FRL-6036-7]
RIN 2070-AB78
Dimethomorph [(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-
dimethoxyphenyl)-1-oxo-2-propenyl]morpholine]; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes a tolerance for residues of the
fungicide dimethomorph [(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-
dimethoxyphenyl)-1-oxo-2-propenyl]morpholine] in or on potatoes.
American Cyanamid Company requested this tolerance under the Federal
Food, Drug and Cosmetic Act (FFDCA), as amended by the Food Quality
Protection Act of 1996 (Pub. L. 104-170).
DATES: This regulation is effective October 13, 1998. Objections and
requests for hearings must be received by EPA on or before December 14,
1998.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300740], must be submitted to: Hearing
Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St.,
SW., Washington, DC 20460. Fees accompanying objections and hearing
requests shall be labeled ``Tolerance Petition Fees'' and forwarded to:
EPA Headquarters Accounting Operations Branch, OPP (Tolerance Fees),
P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any objections and
hearing requests filed with the Hearing Clerk identified by the docket
control number, [OPP-300740], must also be submitted to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. In person,
bring a copy of objections and hearing requests to Rm. 119, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
A copy of objections and hearing requests filed with the Hearing
Clerk may also be submitted electronically by sending electronic mail
(e-mail) to: opp-docket@epamail.epa.gov.
Copies of objections and hearing requests must be submitted as an
ASCII file avoiding the use of special characters and any form of
encryption.
[[Page 54588]]
Copies of objections and hearing requests will also be accepted on
disks in WordPerfect 5.1/6.1 file format or ASCII file format. All
copies of objections and hearing requests in electronic form must be
identified by the docket control number [OPP-300740]. No Confidential
Business Information (CBI) should be submitted through e-mail.
Electronic copies of objections and hearing requests on this rule may
be filed online at many Federal Depository Libraries.
FOR FURTHER INFORMATION CONTACT: By mail: Mary L. Waller, Product
Manager 21, Registration Division (7505C), Office of Pesticide
Programs, Environmental Protection Agency, 401 M St., SW., Washington,
DC 20460. Office location, telephone number, and e-mail address: Room
265, Crystal Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA, (703)
308-9354, e-mail: waller.mary@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: In the Federal Register of March 26, 1997
(62 FR 14418)(FRL-5594-7), EPA issued a notice pursuant to section 408
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a(e)
announcing the filing of a pesticide petition (PP 7F4816) for tolerance
by American Cyanamid Company, Agricultural Products Division, P.O. Box
400, Princeton, NJ 08543-0400. This notice included a summary of the
petition prepared by American Cyanamid Company. There were no comments
received in response to the notice of filing.
The petition requested that 40 CFR 180.493 be amended by
establishing a tolerance for residues of the fungicide dimethomorph
[(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-oxo-2-
propenyl]morpholine], in or on potatoes at 0.05 parts per million
(ppm).
I. Risk Assessment and Statutory Findings
Section 408(b)(2)(A)(i) of the 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) 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)
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. . . .''
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the Final Rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
II. Aggregate Risk Assessment and Determination of Safety
Consistent with 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
dimethomorph and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for a tolerance for residues of
dimethomorph on potatoes at 0.05 ppm. EPA's assessment of the dietary
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. The nature of the toxic effects caused by dimethomorph are
discussed below.
1. Acute toxicity. Technical dimethomorph is relatively non-toxic
when administered acutely to laboratory animals (Toxicity Category III
for Rat Acute Oral, Acute Dermal, Acute Inhalation, Primary Eye
Irritation (conjunctival irritation clearing in 4 days); Toxicity
Category IV for Mice Acute Oral, Z-isomer Rat Acute Oral, E-isomer Rat
Acute Oral, Acute Dermal, Primary Eye Irritation (grade I irritation
clearing in 48 hours), Primary Skin Irritation (grade I irritation at
abraded skin sites only, clearing by day 2); Dermal Sensitization - not
a sensitizer).
2. Subchronic toxicity- i. A 90-day feeding - rat. Technical grade
dimethomorph (98.7% a.i.) was administered in the diet to groups of 10
male and 10 female Charles River CD Sprague-Dawley rats at
concentrations of 0, 40, 200, or 1,000 ppm (0, 2.9, 14.2, or 73 mg/kg/
day for male rats, and 0, 3.2, 15.8, or 82 mg/kg/day for female rats,
respectively) for 13 weeks, 4 days. A Lowest Observed Adverse Effect
Level (LOAEL) was not established because the highest dose tested
produced no biologically significant effects. The No Observed Adverse
Effect Level (NOAEL) is >1,000 ppm (73 mg/kg/day for males, and 82 mg/
kg/day for females).
ii. A 90-day feeding-dog. Dimethomorph (technical, 96.6% a.i.) was
administered to four male and four female Beagle dogs/dose group in the
diet at concentrations of 0, 150, 450, or 1,350 ppm (equivalent to
doses of 0, 5, 15 or 43 mg/kg/day for males, and 0, 6, 15 or 44 mg/kg/
day for females) for 13 weeks. Prostate fibrosis occurred in all four
of the high-dose males but not in any other male. Clinical signs were
limited to intermittent incidences of salivation, lip-licking, tremors,
and subdued behavior; these signs were more prevalent in the 150 and
1,350 ppm groups but were not considered of toxicologic significance.
The critical toxic effect appeared to be a significant decrease in the
mean absolute and relative prostate weights of the high-dose (1,350
ppm) male dogs relative to untreated controls. Therefore, based upon a
decrease in the absolute and relative weights of the prostate and
possible threshold liver effects(increased alkaline phosphatase
activity at weeks 6 and 13), the LOAEL is 1,350 ppm (43 mg/kg/day). The
NOAEL is 450 ppm (15 mg/kg/day).
3. Chronic toxicity-- i. In rats. The LOAEL for systemic toxicity
was 750 ppm (57.7 mg/kg/day) for female rats based on decreased body
weight and significant increase in the incidence of ``ground glass''
foci in the liver and 2,000 ppm (99.9 mg/kg/day) for male rats based on
decreased body weight and increased incidence of arteritis. The
corresponding NOAEL's are 200 ppm (11.9 mg/kg/day) for females, and 750
ppm (36.2 mg/kg/day) for males.
ii. In dogs. At 1,350 ppm, ALK phosphatase activity was increased
throughout the study in both sexes (245% males. 310% females). The
LOAEL for systemic toxicity is 1,350 ppm, based on decreased prostate
weight in males. The NOAEL was 450 ppm.
4. Carcinogenicity-- i. In rats. The test material had no
significant effect on the development of neoplasms in male or female
rats at the doses tested. Dimethomorph was tested at adequate doses
based on significant decreases in body weight (17% and 13%) and body
weight gains (27% and 14%) in females and males, respectively, in the
high dose groups. The LOAEL for systemic
[[Page 54589]]
toxicity was 2,000 ppm in males and 750 ppm in females. The NOAEL's
were 750 ppm (33.9 mg/kg/day) for males and 200 ppm (11.3 mg/kg/day)
for females.
ii. In mice. There were no treatment related increases in the
incidence of any neoplastic lesions. The chemical was adequately tested
based on decreased body weight gain (17% and 22% less than control in
males and females, respectively, at 1,000 mg/kg/day). The NOAEL for
systemic toxicity was 100 mg/kg/day.
5. Developmental toxicity-- i. In rats. Maternal LOAEL = 160 mg/kg/
day, based on decreased mean body weight on gestation days 10-15;
decreased body weight gain on gestation days 10-15, decreased food
consumption days 6-15; Maternal NOAEL = 60 mg/kg/day; Developmental
LOAEL = 160 mg/kg/day based on increased resorptions; Developmental
NOAEL = 60 mg/kg/ day.
ii. In rabbits. Maternal LOAEL = 650 mg/kg/day, based on decreased
body weights and body weight gain. Maternal NOAEL = 300 mg/kg/day. No
developmental toxicity was observed in this study. Developmental NOAEL
= 650 mg/kg/day.
6. Two-generation reproduction study in rats. Parental toxicity
LOAEL = 1,000 ppm, based on decreased body weights and body weight
gain; Parental NOAEL = 300 ppm (20.8 mg/kg/day for males; 24 mg/kg/day
for females); Developmental Toxicity LOAEL = 1,000 ppm based on delayed
incisor eruption at day 10 postpartum; Developmental Toxicity NOAEL =
300 ppm; Reproductive Toxicity NOAEL = 1,000 ppm (69 mg/kg/day for
males; 79.3 mg/kg/day for females).
7. Mutagenicity. The studies indicate that dimethomorph did not
cause gene mutations in Salmonella or E. Coli bacterial strains, as
well as in mammalian gene mutation studies. It was negative for
structural chromosomal aberrations in the mouse micronucleus assay at
up to 5,000 mg/kg after oral treatment, and up to 200 mg/kg when
administered i.p. However, dimethomorph gave positive responses when
tested in CH lung and in human lymphocytes. It was negative in the cell
transformation assay in Syrian hamster embryo cells with and without
activation at up to cytotoxic levels.
8. Dermal penetration. Radio-labeled 14C-dimethomorph
(97.6%; labeled in the chlorophenyl ring) was administered dermally to
4 male SD rats/group in water for 8 hours at doses of 7.73 (2.5% w/v
aqueous suspension) or 79.62(25% w/v aqueous suspension)mg/kg. Dermal
absorption was 0.05%, 0.07% and 0.27% of the administered dose from
rats 4, 8, and 24 hours after dermal treatment at 7.73 mg/kg, and
0.02%, 0.16% and 0.12% of the dose at 79.62 mg/kg. Six days after
treatment the percent total absorption of the dose in the 7.73 and
79.62 mg/kg was 4.76 and 1.20 percent respectively. Mean percent
recovery of the 14C for dose levels of 7.73 and 79.62 mg/kg
was 104.1% and 92.1%, respectively.
9. Neurotoxicity. There are no acute, subchronic, or developmental
neurotoxicity studies available in the data base for dimethomorph.
However, in none of the subchronic, chronic, developmental, or
reproduction studies was there any indication that the nervous system
was affected by administration of dimethomorph. No evidence of
neurotoxicity was observed in the available data base.
10. General metabolism. Rat Oral administration of dimethomorph (10
mg/kg single dose; 10 mg/kg 14-day repeated dose; 10 mg/kg 7-day
repeated dose; 500 mg/kg single dose) results in rapid excretion into
the urine and feces of rats. For all treatment protocols, most (80-90%)
of the radiolabel administered was excreted in the feces. A
considerably smaller amount (6-16%) was excreted in the urine and only
minimal levels (0.1-0.4%) were detected in the organs and tissues.
Rapid absorption may be inferred by the rapid excretion of metabolites
in the urine and bile. Saturation of absorption following single high
doses (500 mg/kg) was indicated by large amounts (50%) of
radioactivity in the feces being associated with parent compound. For
low- or high-dose treatment, urinary excretion in female rats tended to
be greater (up to 2-fold in low-dose rats) than that of male rats.
Retention of dimethomorph or 14C-dimethomorph-derived
radioactivity was generally 1% for most tissues although
the liver exhibited slightly higher levels (1.4%) and higher levels in
the gastrointestinal tract organswas due to radioactivity in the
lumenal contents. Urinary metabolites resulted from demethylation of
the dimethoxyphenyl ring and oxidation of the morpholine ring. Biliary
excretion exhibited first-order kinetics with a low-dose (10 mg/kg)
half-life of approximately 3 hours and a high-dose (500 mg/kg) half-
life of 11 hours for males and about 6 hours for females. Biliary
metabolites accounted for most of the fecal excretion following low-
dose treatment. The major biliary metabolites were glucuronides of one
and possibly two of the compounds produced by demethylation of the
dimethoxyphenyl ring. The report provided a proposed metabolic pathway
for dimethomorph.
B. Toxicological Endpoints
1. Acute toxicity. EPA did not select a dose and endpoint for an
acute dietary risk assessment due to the lack of toxicological effects
attributable to a single exposure (dose) in either the rat or the
rabbit developmental toxicity studies. Therefore an acute RfD was not
calculated.
2. Short- and intermediate-term toxicity. EPA established NOAELs
of 60 mg/kg/day and 15 mg/kg/day to be used in risk assessments for
workers for short- and intermediate-term dermal and inhalation
exposures, respectively. The NOAEL for short-term exposure is based on
the maternal NOAEL established in the rat developmental toxicity study
and the NOAEL for intermediate-term exposure is based on the NOAEL
established in the 90-day dog feeding study. As the exposures are by
dermal and inhalation routes and these are oral studies, a dermal
absorption factor of 5 percent, derived from the dermal absorption
study, is included in the risk assessment. Inhalation absorption is
assumed to be 100%.
3. Chronic toxicity. EPA selected a NOAEL of 11 mg/kg/day
established in the chronic oncogenicity feeding study in the rat. This
NOAEL was nearly identical to that established in the rat chronic
feeding study. The LOAEL was 46.3 mg/kg/day based on decreased body
weight and liver lesions in female rats. A 100 fold safety factor was
applied (10 for inter-species extrapolation, and 10 for intra-species
variation). Thus, the chronic RfD was calculated to be 0.1 mg/kg/day.
The EPA FQPA Safety Factor Committee determined that, for chronic
dietary risk assessment, the 10x factor to account for enhanced
sensitivity to infants and children (as required by FQPA) should be
removed. Neither a chronic dermal nor inhalation endpoint were
identified as the current use pattern does not indicate a concern for
long term exposure.
4. Carcinogenicity. There was no increased incidence of neoplasms
in the rat chronic or carcinogenicity studies or in the mouse
carcinogenicity study. EPA determined that the chemical had been tested
at adequate dosage in the rat study, as demonstrated by the high
incidence of arteritis in males, and the pronounced decrease in body
weight in females at the mid- and high-dose levels. EPA also determined
that the high dose tested (1,000 mg/kg/day) in the mouse study was the
maximum dose required by the test guidelines for a dietary oncogenicity
study. Therefore,
[[Page 54590]]
EPA classified dimethomorph as ``not likely'' to be a human carcinogen.
C. Exposures and Risks
1. From food and feed uses. Time-limited tolerances are established
for residues of dimethomorph in or on cantaloupes, cucumbers, tomatoes,
squash and watermelons at 1.0 ppm, potatoes at 0.05 ppm, tomato paste
at 6.0 ppm and tomato puree at 2.0 ppm in connection with use of the
pesticide under section 18 emergency exemptions granted by EPA. Risk
assessments were conducted by EPA to assess dietary exposures from
dimethomorph as follows:
i. Acute exposure and risk. Acute dietary 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 one day or single exposure. An acute dietary exposure assessment
is not required because no acute toxicological effects endpoints were
identified for dimethomorph due to the lack of toxicological effects
attributable to a single exposure (dose) in either the rat or the
rabbit developmental toxicity studies.
ii. Chronic exposure and risk. EPA's Dietary Exposure Evaluation
Model (DEEM89) was used for conducting a chronic dietary (food only)
exposure analysis (risk assessment). The analysis evaluates individual
food consumption, as reported by respondents in the USDA 1989-1992
Nationwide Food Consumption Survey, and accumulates exposure to the
chemical for each commodity. In conducting this chronic dietary (food)
risk assessment, EPA made very conservative assumptions: that all
commodities having dimethomorph tolerances will contain residues of
dimethomorph and those residues will be at the level of the tolerance.
These assumptions result in an overestimate of human dietary exposure.
All section 18 tolerances (cantaloupes, watermelons, cucumbers, squash,
tomatoes) are included in this dietary risk assessment.
Using the assumptions and data parameters described above, the
DEEM89 exposure analysis results in a theoretical maximum residue
contribution (TMRC) (exposure) that is equivalent to the following
percentages of the chronic RfD:
------------------------------------------------------------------------
TMRC food (mg/kg/
Population Subgroup day) Percent RfD
------------------------------------------------------------------------
U.S. Population (48 states)............. 0.0018 1.8
Nursing Infants (<1 year="" old)...........="" 0.00054="" 0.5="" non-nursing="" infants=""><1 year="" old).......="" 0.0021="" 2.1="" children="" (1-6="" years="" old)................="" 0.0039="" 3.9="" children="" (7-12="" years="" old)...............="" 0.0027="" 2.7="" females="" (13-19="" yrs/not="" preg.="" or="" nursing)="" 0.0020="" 2.0="" males="" (13-19="" years).....................="" 0.0019="" 1.9="" u.s.="" population="" -="" summer="" season.........="" 0.0021="" 2.1="" northeast="" region........................="" 0.0021="" 2.1="" hispanics...............................="" 0.0020="" 2.0="" non-hispanic="" other="" than="" black="" or="" white..="" 0.0021="" 2.1="" ------------------------------------------------------------------------="" epa="" does="" not="" consider="" the="" chronic="" dietary="" risk="" to="" exceed="" the="" agency's="" level="" of="" concern.="" 2.="" from="" drinking="" water.="" there="" is="" no="" established="" maximum="" contaminant="" level="" for="" dimethomorph="" in="" drinking="" water.="" no="" health="" advisory="" levels="" have="" been="" established="" for="" residues="" of="" dimethomorph="" in="" drinking="" water.="" the="" predicted="" dimethomorph="" surface="" and="" ground="" water="" concentrations="" are="" well="" below="" epa's="" drinking="" water="" level="" of="" concern="" (dwloc).="" epa="" used="" the="" sci-grow="" (screening="" concentration="" in="" ground="" water)="" model="" to="" estimate="" the="" estimated="" environmental="" concentration="" (eec)="" of="" dimethomorph="" residues="" in="" ground="" water.="" the="" reported="" eec="" for="" dimethomorph="" residues="" using="" sci-grow="" is="" 0.26="" ppb.="" epa="" used="" geneec="" (generic="" estimated="" environmental="" concentration)="" model="" to="" estimate="" acute="" and="" chronic="" eecs="" of="" dimethomorph="" residues="" in="" surface="" water.="" the="" geneec="" model="" estimated="" that,="" with="" the="" present="" use="" pattern,="" surface="" water="" concentrations="" of="" dimethomorph="" ranged="" from="" a="" peak="" of="" 28="" ppb="" to="" a="" 56="" day="" concentration="" of="" 24="" ppb.="" epa's="" level="" of="" concern="" for="" chronic="" exposure="" to="" residues="" of="" dimethomorph="" range="" from="" 960="" ppb="" for="" children="" 1-6="" years="" old="" to="" 3,400="" ppb="" for="" the="" u.s.="" population="" and="" males="" 13="" years="" and="" older.="" therefore,="" exposure="" from="" water="" is="" below="" epa's="" level="" of="" concern="" for="" all="" of="" the="" populations="" examined.="" i.="" acute="" exposure="" and="" risk.="" because="" no="" acute="" dietary="" endpoint="" was="" determined,="" an="" acute="" water="" and="" dietary="" exposure="" risk="" assessment="" is="" not="" required.="" ii.="" chronic="" exposure="" and="" risk.="" epa="" conducts="" the="" drinking="" water="" risk="" assessment="" by="" using="" the="" worst="" case="" scenario="" of="" eec="" found="" from="" either="" ground="" or="" surface="" water.="" the="" eec="" reported="" for="" dimethomorph="" residues="" in="" ground="" water="" using="" sci-grow="" is="" 0.26="" ppb.="" this="" is="" much="" less="" than="" the="" surface="" water="" eecs="" (24.4="" ppb="" for="" 56-days)="" generated="" using="" geneec.="" therefore,="" only="" the="" surface="" water="" eecs="" were="" used="" in="" conducting="" the="" aggregate="" dietary="" (food="" +="" water)="" risk="" assessment.="" based="" on="" the="" chronic="" dietary="" (food)="" exposure="" and="" using="" default="" body="" weights="" and="" water="" consumption="" figures,="" chronic="" drinking="" water="" levels="" of="" concern="" (dwloc)="" for="" drinking="" water="" were="" calculated.="" to="" calculate="" the="" chronic="" dwloc,="" the="" chronic="" dietary="" food="" exposure="" (from="" deem="" analysis)="" was="" subtracted="" from="" the="" chronic="" rfd.="" dwlocs="" were="" then="" calculated="" using="" the="" default="" body="" weights="" and="" drinking="" water="" consumption="" figures.="" epa's="" surface="" drinking="" water="" levels="" of="" concern="" from="" chronic="" exposure="" to="" dimethomorph="" using="" modeling="" data="" are="" 3,400="" ppb="" for="" the="" u.s.="" population="" and="" males="" 13="" years="" and="" older,="" 2,900="" ppb="" for="" females="" 13="" years="" and="" older,="" and="" 960="" ppb="" for="" children="" (1-6="" years="" of="" age).="" these="" levels="" are="" all="" greater="" than="" the="" geneec="" concentration="" level="" (24.4="" ppm="" for="" 56-days).="" therefore,="" epa="" does="" not="" expect="" exposure="" to="" dimethomorph="" in="" drinking="" water="" to="" be="" above="" our="" level="" of="" concern.="" 3.="" from="" non-dietary="" exposure.="" there="" are="" no="" registered="" or="" proposed="" residential="" uses="" for="" dimethomorph.="" therefore,="" residential="" or="" inhalation="" exposures="" were="" not="" evaluated="" in="" the="" risk="" assessment.="" a="" risk="" assessment="" was="" evaluated="" for="" occupational="" risk="" to="" workers="" who="" could="" be="" exposed="" to="" dimethomorph="" through="" simultaneous="" dermal="" and="" inhalation="" exposure.="" agricultural="" workers="" evaluated="" in="" this="" analysis="" include:="" ground="" mixer/="" loaders,="" ground="" applicators,="" aerial="" mixer/loaders="" and="" aerial="" applicators.="" the="" dermal="" and="" inhalation="" short-term="" margin="" of="" exposure="" (moe)="" ranged="" from="" 1,200="" for="" aerial="" mixer/loaders="" using="" the="" wettable="" [[page="" 54591]]="" powder="" (wp)="" to="" 190,000="" for="" aerial="" applicators.="" the="" intermediate-term="" moes="" range="" from="" 290="" for="" aerial="" mixer/loaders="" using="" wp="" to="" 47,000="" for="" aerial="" applicators.="" exposure="" from="" post-application="" of="" dimethomorph="" resulted="" in="" moes="" ranging="" from="" 23,000="" for="" short-term="" to="" 5,800="" for="" intermediate-term.="" none="" of="" these="" moes="" exceed="" hed's="" level="" of="" concern="" (i.e.,="" acceptable="" moe=""> 100) for occupationally exposed workers.
Therefore, these workers are unlikely to experience adverse health
effects under the conditions evaluated.
4. Cumulative exposure to substances with common mechanism of
toxicity. Section 408(b)(2)(D)(v) 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.''
EPA does not have, at this time, available data to determine
whether dimethomorph has a common mechanism of toxicity with other
substances or how to include this pesticide in a cumulative risk
assessment. Unlike other pesticides for which EPA has followed a
cumulative risk approach based on a common mechanism of toxicity,
dimethomorph 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 dimethomorph 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 the Final Rule
for Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997).
D. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. An acute aggregate risk assessment is not required
because no acute dietary endpoint was determined.
2. Chronic risk. EPA concludes that the chronic exposure to
dimethomorph from food will utilize 1.8% of the RfD for the U.S.
population, 2.0% for females (13+ not pregnant or nursing), 1.9% for
males 13 years and older, and 3.9% for children ages 1 through 6 years
of age. The surface drinking water levels of concern from chronic
exposure to dimethomorph using modeling data are 3,400 ppb for the U.S.
Population and males 13 years and older, 2,900 ppb for females 13 years
and older and 960 ppb for children (1-6 years of age). These levels are
all greater than the GENEEC chronic concentration level (24.4 ppb for
56 days) and the SCI-GROW ground water level of 0.26 ppb. There are no
registered residential uses of dimethomorph. EPA generally has no
concern for exposures below 100% of the RfD because the RfD represents
the level at or below which daily aggregate dietary exposure over a
lifetime will not pose appreciable risks to human health. Despite the
potential for exposure to dimethomorph in drinking water, EPA does not
expect the aggregate exposure to exceed 100% of the RfD. Therefore, EPA
concludes that there is reasonable certainty that no harm will result
to either adults or children from chronic aggregate exposure to
dimethomorph residues.
3. Short- and intermediate-term risk. Short- and intermediate-term
aggregate exposure takes into account chronic dietary food and water
(considered to be a background exposure level) plus indoor and outdoor
residential exposure. Although short- and intermediate-term endpoints
were identified, there are no residential uses for dimethomorph.
Therefore, an aggregate risk assessment is not required for short- and
intermediate-term endpoints.
4. Aggregate cancer risk for U.S. population. Dimethomorph was
classified as ``not likely'' to be a human carcinogen). Therefore, a
carcinogenic aggregate risk assessment is not required.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
from aggregate exposure to dimethomorph residues.
E. Aggregate Risks and Determination of Safety for Infants and Children
1. Safety factor for infants and children-- i. In general. In
assessing the potential for additional sensitivity of infants and
children to residues of dimethomorph, EPA considered data from
developmental toxicity studies in the rat and rabbit and a two-
generation reproduction study in the rat. The developmental toxicity
studies are designed to evaluate adverse effects on the developing
organism resulting from maternal pesticide exposure during gestation.
Reproduction studies provide information relating to effects from
exposure to the pesticide on the reproductive capability of mating
animals and data on systemic toxicity. The toxicology data on
dimethomorph provides no indication of enhanced sensitivity of infants
and children based on the results from developmental studies conducted
with rats and rabbits as well as a two-generation reproduction study
conducted with rats. In neither the rat developmental toxicity study
nor in the 2-generation study were any toxic effects observed at doses
lower than in the parents. No developmental toxicity was demonstrated
in the rabbit developmental toxicity study.
FFDCA of section 408 provides that EPA shall apply an additional
tenfold margin of safety for infants and children in the case of
threshold effects to account for pre-and post-natal toxicity and the
completeness of the database unless EPA determines that a different
margin of safety will be safe for infants and children. Margins of
safety are incorporated into EPA risk assessments either directly
through use of a margin of exposure (MOE) analysis or through using
uncertainty (safety) factors in calculating a dose level that poses no
appreciable risk to humans. EPA believes that reliable data support
using the standard uncertainty factor (usually 100 for combined inter-
and intra-species variability)) and not the additional tenfold MOE/
uncertainty factor when EPA has a complete data base under existing
guidelines and when the severity of the effect in infants or children
or the potency or unusual toxic properties of a compound do not raise
concerns regarding the adequacy of the standard MOE/safety factor.
ii. Pre- and post-natal sensitivity. The data provided no evidence
of special sensitivity of rats or rabbits to in utero and/or postnatal
exposure to dimethomorph. In the prenatal developmental study in rats,
an increased incidence of post implantation loss, considered by EPA to
be minimal, was observed in the presence of maternal toxicity. In the
developmental toxicity in rabbits, no evidence of developmental
toxicity was seen, even at the highest dose tested. In the two-
generation study in rats, effects in the offspring were observed only
at dose levels that produced parental toxicity. There is no evidence
that dimethomorph is a neurotoxic chemical. EPA determined that the 10x
factor to account for enhanced sensitivity of infants and children be
removed.
iii. Conclusion. There is a complete toxicity database for
dimethomorph and exposure data is complete or is estimated based on
data that reasonably accounts for potential exposures.
2. Acute risk. An acute aggregate risk assessment is not required
because no acute dietary endpoints were identified for dimethomorph.
3. Chronic risk. Using the exposure assumptions described above,
EPA has concluded that aggregate exposure to dimethomorph from food
will utilize 4% of the RfD for infants and children.
[[Page 54592]]
EPA generally has no concern for exposures below 100% of the RfD
because the RfD represents the level at or below which daily aggregate
dietary exposure over a lifetime will not pose appreciable risks to
human health. Despite the potential for exposure to dimethomorph in
drinking water, EPA does not expect the aggregate exposure to exceed
100% of the RfD.
4. Short- or intermediate-term risk. Although short- and
intermediate-term endpoints were identified, there are no residential
uses for dimethomorph. Therefore, an aggregate risk assessment is not
required for short- and intermediate-term endpoints.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to infants and children from aggregate exposure to dimethomorph
residues.
III. Other Considerations
A. Metabolism In Plants and Animals
The nature of the residue in plants and in animals are adequately
understood. The major residue of regulatory concern is the parent
dimethomorph compound. Tolerances on animal commodities are not
required in conjunction with this use. There is no need for additional
poultry metabolism data at this time since no uses are pending on
poultry feed items.
B. Analytical Enforcement Methodology
An adequate method is available for enforcement of the proposed
tolerances. Method FAMS 002-04 (High Performance Liquid Chromatography
(HPLC), Ultraviolet (UV) detection) is adequate for determining
residues of dimethomorph per se in/on potatoes. A confirmatory method
is also available (FAM 022-03).
The method may be requested from: Calvin Furlow, PIRIB, IRSD
(7502C), Office of Pesticide Programs, Environmental Protection Agency,
401 M St., SW., Washington, DC 20460. Office location and telephone
number: Rm 101FF, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA 22202, (703-305-5229).
C. Magnitude of Residues
EPA has concluded that residue data submitted in support of the
tolerance for imported potatoes indicate that a tolerance level of 0.05
ppm is an adequate level for domestic potatoes. In addition, domestic
field trial data supported the tolerance level of 0.05 ppm on potatoes
and indicated that dimethomorph residues do not pose an adverse health
risk to humans under the use conditions. Therefore, EPA has no
objection to the establishment of a tolerance of 0.05 ppm for residues
of the fungicide dimethomorph in/on potatoes under 40 CFR 180.493.
D. International Residue Limits
There are no Canadian, Mexican, or Codex MRLs established for
dimethomorph for the commodities associated with this request:
consequently, a discussion of international harmonization is not
relevant.
E. Rotational Crop Restrictions
EPA concluded it is permissible to rotate to leafy vegetables and
root crops after a 120-day plant back interval. Rotation to potatoes
will be permitted at any time. For crops other than potatoes, leafy
vegetables, and root crops, a 1-year plant back interval will be
required.
IV. Conclusion
Therefore, the tolerance is established for residues of
dimethomorph [(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-
oxo-2-propenyl]morpholine] in potatoes at 0.05 ppm.
V. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation issued by EPA under
new section 408(e) and (l)(6) as was provided in the old section 408
and in section 409. However, the period for filing objections is 60
days, rather than 30 days. EPA currently has procedural regulations
which govern the submission of objections and hearing requests. These
regulations will require some modification to reflect the new law.
However, until those modifications can be made, EPA will continue to
use those procedural regulations with appropriate adjustments to
reflect the new law.
Any person may, by December 14, 1998, file written objections to
any aspect of this regulation and may also request a hearing on those
objections. Objections and hearing requests must be filed with the
Hearing Clerk, at the address given above (40 CFR 178.20). A copy of
the objections and/or hearing requests filed with the Hearing Clerk
should be submitted to the OPP docket for this rulemaking. The
objections submitted must specify the provisions of the regulation
deemed objectionable and the grounds for the objections (40 CFR
178.25). Each objection must be accompanied by the fee prescribed by 40
CFR 180.33(i). If a hearing is requested, the objections must include a
statement of the factual issues on which a hearing is requested, the
requestor's contentions on such issues, and a summary of any evidence
relied upon by the requestor (40 CFR 178.27). A request for a hearing
will be granted if the Administrator determines that the material
submitted shows the following: There is genuine and substantial issue
of fact; there is a reasonable possibility that available evidence
identified by the requestor would, if established, resolve one or more
of such issues in favor of the requestor, taking into account
uncontested claims or facts to the contrary; and resolution of the
factual issues in the manner sought by the requestor would be adequate
to justify the action requested (40 CFR 178.32). Information submitted
in connection with an objection or hearing request may be claimed
confidential by marking any part or all of that information as CBI.
Information so marked will not be disclosed except in accordance with
procedures set forth in 40 CFR part 2. A copy of the information that
does not contain CBI must be submitted for inclusion in the public
record. Information not marked confidential may be disclosed publicly
by EPA without prior notice.
VI. Public Record and Electronic Submissions
EPA has established a record for this rulemaking under docket
control number [OPP-300740] (including any comments and data submitted
electronically). A public version of this record, including printed,
paper versions of electronic comments, which does not include any
information claimed as CBI, is available for inspection from 8:30 a.m.
to 4 p.m., Monday through Friday, excluding legal holidays. The public
record is located in Room 119 of the Public Information and Records
Integrity Branch, Information Resources and Services Division (7502C),
Office of Pesticide Programs, Environmental Protection Agency, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
Electronic comments may be sent directly to EPA at:
opp-docket@epamail.epa.gov.
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of encryption.
The official record for this rulemaking, as well as the public
version, as described above will be kept in paper form. Accordingly,
EPA will transfer any copies of objections and hearing requests
received electronically into printed, paper form as they are
[[Page 54593]]
received and will place the paper copies in the official rulemaking
record which will also include all comments submitted directly in
writing. The official rulemaking record is the paper record maintained
at the Virginia address in ``ADDRESSES'' at the beginning of this
document.
VII. Regulatory Assessment Requirements
A. Certain Acts and Executive Orders
This final rule establishes a tolerance 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). 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., or impose any enforceable
duty or contain any unfunded mandate as described under Title II of the
Unfunded Mandates Reform Act of 1995 (UMRA) (Pub. L. 104-4). Nor does
it require any prior consultation as specified by Executive Order
12875, entitled Enhancing the Intergovernmental Partnership (58 FR
58093, October 28, 1993), or special considerations as required by
Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994), or require OMB review in
accordance with Executive Order 13045, entitled Protection of Children
from Environmental Health Risks and Safety Risks (62 FR 19885, April
23, 1997).
In addition, 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. Nevertheless, the Agency has
previously assessed whether establishing tolerances, exemptions from
tolerances, raising tolerance levels or expanding exemptions might
adversely impact small entities and concluded, as a generic matter,
that there is no adverse economic impact. The factual basis for the
Agency's generic certification for tolerance actions published on May
4, 1981 (46 FR 24950) and was provided to the Chief Counsel for
Advocacy of the Small Business Administration.
B. Executive Order 12875
Under Executive Order 12875, entitled Enhancing the
Intergovernmental Partnership (58 FR 58093, October 28, 1993), EPA may
not issue a regulation that is not required by statute and that creates
a mandate upon a State, local, or tribal government, unless the Federal
government provides the funds necessary to pay the direct compliance
costs incurred by those governments. If the mandate is unfunded, EPA
must provide to OMB a description of the extent of EPA's prior
consultation with representatives of affected State, local, and tribal
governments, the nature of their concerns, copies of any written
communications from the governments, and a statement supporting the
need to issue the regulation. In addition, Executive Order 12875
requires EPA to develop an effective process permitting elected
officials and other representatives of State, local, and tribal
governments ``to provide meaningful and timely input in the development
of regulatory proposals containing significant unfunded mandates.''
Today's rule does not create an unfunded Federal mandate on State,
local, or tribal governments. The rule does not impose any enforceable
duties on these entities. Accordingly, the requirements of section 1(a)
of Executive Order 12875 do not apply to this rule.
C. Executive Order 13084
Under Executive Order 13084, entitled Consultation and Coordination
with Indian Tribal Governments (63 FR 27655, May 19,1998), EPA may not
issue a regulation that is not required by statute, that significantly
or uniquely affects the communities of Indian tribal governments, and
that imposes substantial direct compliance costs on those communities,
unless the Federal government provides the funds necessary to pay the
direct compliance costs incurred by the tribal governments. If the
mandate is unfunded, EPA must provide to OMB, in a separately
identified section of the preamble to the rule, a description of the
extent of EPA's prior consultation with representatives of affected
tribal governments, a summary of the nature of their concerns, and a
statement supporting the need to issue the regulation. In addition,
Executive Order 13084 requires EPA to develop an effective process
permitting elected officials and other representatives of Indian tribal
governments ``to provide meaningful and timely input in the development
of regulatory policies on matters that significantly or uniquely affect
their communities.''
Today's rule does not significantly or uniquely affect the
communities of Indian tribal governments. This action does not involve
or impose any requirements that affect Indian tribes. Accordingly, the
requirements of section 3(b) of Executive Order 13084 do not apply to
this rule.
VIII. Submission to Congress and the Comptroller General
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
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 the rule in the Federal Register. This 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: September 30, 1998.
Marcia E. Mulkey,
Director, Office of Pesticide Programs.
Therefore, 40 CFR chapter I is amended as follows:
PART 180--[AMENDED]
1. The authority citation for part 180 continues to read as
follows:
Authority: 21 U.S.C. 346a and 371.
2. In section 180.493, by revising paragraph (a) to read as
follows:
Sec. 180.493 Dimethomorph [(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-
dimethoxyphenyl)-1-oxo-2-propenyl]morpholine]; tolerances for residues.
(a) General. A tolerance is established for the residues of the
fungicide dimethomorph [(E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-
dimethoxyphenyl)-1-oxo-2-propenyl]morpholine] in or on the following
commodity:
------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
Potatoes.................................. 0.05
------------------------------------------------------------------------
[[Page 54594]]
* * * * *
[FR Doc. 98-27396 Filed 10-9-98; 8:45 am]
BILLING CODE 6560-50-F
