Document ID: EPA-HQ-OPP-2008-0275-0004
Agency: epa
Document Type: Rule
Title: Iodosulfuron-methyl-sodium; Pesticide Tolerances
Posted Date: 2009-05-20T04:00Z

[Federal Register: May 20, 2009 (Volume 74, Number 96)]
[Rules and Regulations]               
[Page 23640-23645]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20my09-14]                         

[[Page 23640]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2009-0275; FRL-8412-6]

 
Iodosulfuron-methyl-sodium; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
iodosulfuron-methyl-sodium in or on wheat, forage; wheat, grain; wheat, 
hay; and wheat, straw. Bayer Cropscience requested these tolerances 
under the Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective May 20, 2009. Objections and 
requests for hearings must be received on or before July 20, 2009, and 
must be filed in accordance with the instructions provided in 40 CFR 
part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION ).

ADDRESSES: EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2009-0275. All documents in the 
docket are listed in the docket index available at http://
www.regulations.gov. Although listed in the index, some information is 
not publicly available, e.g., Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. Certain 
other material, such as copyrighted material, is not placed on the 
Internet and will be publicly available only in hard copy form. 
Publicly available docket materials are available in the electronic 
docket at http://www.regulations.gov, or, if only available in hard 
copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac 
Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket 
Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The Docket Facility telephone number is (703) 
305-5805.

FOR FURTHER INFORMATION CONTACT: Hope Johnson, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-5410; e-mail address: johnson.hope@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected entities may include, but are not limited to those 
engaged in the following activities:
     Crop production (NAICS code 111).
     Animal production (NAICS code 112).
     Food manufacturing (NAICS code 311).
     Pesticide manufacturing (NAICS code 32532).
    This listing is not intended to be exhaustive, but rather to 
provide a guide for readers regarding entities likely to be affected by 
this action. Other types of entities not listed in this unit could also 
be affected. The North American Industrial Classification System 
(NAICS) codes have been provided to assist you and others in 
determining whether this action might apply to certain entities. If you 
have any questions regarding the applicability of this action to a 
particular entity, consult the person listed under FOR FURTHER 
INFORMATION CONTACT.

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

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

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, 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-OPP-2009-0275 in the subject line on the first 
page of your submission. All requests must be in writing, and must be 
mailed or delivered to the Hearing Clerk as required by 40 CFR part 178 
on or before July 20, 2009.
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please submit a copy of 
the filing that does not contain any CBI for inclusion in the public 
docket that is described in ADDRESSES. Information not marked 
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA 
without prior notice. Submit this copy, identified by docket ID number 
EPA-HQ-OPP-2009-0275, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail: Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery: OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only 
accepted during the Docket Facility's normal hours of operation (8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays). 
Special arrangements should be made for deliveries of boxed 
information. The Docket Facility telephone number is (703) 305-5805.

II. Petition for Tolerance

    In the Federal Register of July 9, 2008 (73 FR 39289) (FRL-8371-2), 
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition (PP 1F6299) 
by Bayer Cropscience, 2 Alexander Drive, Research Triangle Park, NC 
27709. The petition requested that 40 CFR 180.580 be amended by 
establishing tolerances for residues of the herbicide iodosulfuron-
methyl-sodium, methyl 4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5 triazin-2-
yl) ureidosulfonyl] benzoate, sodium salt, in or on wheat, grain at 
0.02 parts per million (ppm); wheat, forage at 0.06 ppm; wheat, straw 
at 0.05 ppm; and wheat, hay at 0.05 ppm. That notice referenced a 
summary of the petition prepared by Bayer Cropscience, the registrant, 
which is available to the public in the docket, 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 
concluded that 40 CFR 180.580 can be amended by establishing tolerances 
for residues of the herbicide iodosulfuron-methyl sodium, methyl 4-
iodo-2-[3-(4-methoxy-6-methyl-1,3,5 triazin-2-yl) ureidosulfonyl] 
benzoate, sodium salt, in or on wheat, grain at 0.02 ppm; wheat, straw 
at 0.05 ppm; wheat, hay at 0.05ppm; and wheat, forage at 0.10 ppm

[[Page 23641]]

instead of the petitioned for 0.06 ppm for wheat, forage. 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 section 408(b)(2)(D) of FFDCA, and the factors 
specified in section 408(b)(2)(D) of FFDCA, EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has sufficient data to assess the hazards of and to 
make a determination on aggregate exposure for the petitioned-for 
tolerances for residues of iodosulfuron-methyl-sodium on wheat, forage 
at 0.06 ppm; wheat, grain at 0.02 ppm; wheat, hay at 0.05 ppm; and 
wheat, straw at 0.05 ppm. EPA's assessment of exposures and risks 
associated with establishing tolerances 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. Specific information on the studies received and the nature 
of the adverse effects caused by iodosulfuron-methyl-sodium 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 document Iodosulfuron-Methyl-Sodium; 
Human-Health Risk Assessment for Proposed Section 3 New Use on Wheat, 
page 37 in docket ID number EPA-HQ-OPP-2009-0275.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, a toxicological point of departure (POD) is 
identified as the basis for derivation of reference values for risk 
assessment. The POD may be defined as the highest dose at which no 
adverse effects are observed (the NOAEL) in the toxicology study 
identified as appropriate for use in risk assessment. However, if a 
NOAEL cannot be determined, the lowest dose at which adverse effects of 
concern are identified (the LOAEL) or a Benchmark Dose (BMD) approach 
is sometimes used for risk assessment. Uncertainty/safety factors (UFs) 
are used in conjunction with the POD to take into account uncertainties 
inherent in the extrapolation from laboratory animal data to humans and 
in the variations in sensitivity among members of the human population 
as well as other unknowns. Safety is assessed for acute and chronic 
dietary risks by comparing aggregate food and water exposure to the 
pesticide to the acute population adjusted dose (aPAD) and chronic 
population adjusted dose (cPAD). The aPAD and cPAD are calculated by 
dividing the POD by all applicable UFs. Aggregate short-, intermediate-
, and chronic-term risks are evaluated by comparing food, water, and 
residential exposure to the POD to ensure that the margin of exposure 
(MOE) called for by the product of all applicable UFs is not exceeded. 
This latter value is referred to as the Level of Concern (LOC).
    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 
greater than that 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.
    Iodosulfuron-methyl-sodium was assessed in a complete battery of 
subchronic (mice and rats), chronic (mice, rats, and dogs), 
carcinogenicity (mice and rats), developmental (rat and rabbit) and 
reproductive (rat) toxicity studies. In general high doses typically in 
the range of greater than 300 mg/kg/day were required to cause systemic 
toxicity characterized as decreases in body weight, body weight gain, 
hepatotoxicity in mice and/or dogs and gross and histopathological 
changes in the hematopoietic system in dogs. Developmental toxicity was 
seen only at the limit dose in the rats, no developmental toxicity was 
seen in the rabbit, and no reproductive toxicity was seen in the rat.
    Hematopoietic-related toxicity was only seen in female dogs in both 
the subchronic and chronic toxicity studies. The hematopoietic system 
involved in the production of blood includes primarily the bone marrow, 
spleen, and lymph nodes. In both the subchronic and chronic studies, 
microscopic pathology of the bone marrow and spleen were seen at 
approximately (50 m/k/day; LOAEL). The NOAEL was 8 mg/kg/day.
    The toxicity profile of iodosulfuron-methyl-sodium indicates that 
the dog to be the most sensitive species with the effects on the 
hematopoietic system being the most sensitive endpoint. The NOAEL 
(approximately 8 mg/kg/day) based on the most sensitive endpoint is 
used for assessing risk to intermediate (oral, dermal and inhalation 
routes) and chronic (oral, dermal and inhalation routes) durations 
resulting from exposure to iodosulfuron-methyl-sodium.
    A summary of the toxicological endpoints for iodosulfuron-methyl-
sodium used for human risk assessment can be found at http://
www.regulations.gov in document Iodosulfuron-Methyl-Sodium; Human-
Health Risk Assessment for Proposed Section 3 New Use on Wheat, page 13 
in docket ID number EPA-HQ-OPP-2009-0275.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to iodosulfuron-methyl-sodium, EPA considered exposure under 
the petitioned-for tolerances as well as all existing iodosulfuron-
methyl-sodium tolerances in (40 CFR 180.580). EPA assessed dietary 
exposures from iodosulfuron-methyl-sodium in food as follows:
    i. Acute exposure. Quantitative acute dietary exposure and risk 
assessments are performed for a food-use pesticide, if a toxicological 
study has indicated the possibility of an effect of concern occurring 
as a result of a 1-day or single exposure.
    In estimating acute dietary exposure, EPA used food consumption 
information from the United States Department of Agriculture (USDA), 
1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by 
Individuals (CSFII). As to residue levels in food, EPA used tolerance 
level residues and 100% crop treated

[[Page 23642]]

information to complete the acute dietary exposure assessment. Drinking 
water values were incorporated directly into the assessment.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA, 1994-1996 
and 1998 CSFII. As to residue levels in food, EPA used tolerance level 
residues and 100% crop treated information to complete the chronic 
dietary exposure assessment. Drinking water values were incorporated 
directly into the assessment.
    iii. Cancer. The Agency determined that iodosulfuron-methyl-sodium 
was ``not likely to be a human carcinogen'' with regards to its 
potential as a human carcinogen. This decision was based on the lack of 
evidence for carcinogenicity in mice and rats. Iodosulfuron-methyl-
sodium was negative for mutagenicity in various assays. Furthermore, 
registered sulfonyl urea compounds (structurally similar compounds) 
have been found to be non-carcinogenic. Based on this weight-of-
evidence, an exposure assessment to evaluate cancer risk for 
iodosulfuron-methyl-sodium was not necessary.
    iv. Anticipated residue and percent crop treated (PCT) information. 
EPA did not use anticipated residue or PCT information in the dietary 
assessment for iodosulfuron-methyl-sodium. Tolerance level residues and 
100 PCT were assumed for all food commodities.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for iodosulfuron-methyl-sodium in drinking water. These 
simulation models take into account data on the physical, chemical, and 
fate/transport characteristics of iodosulfuron-methyl-sodium. Further 
information regarding EPA drinking water models used in pesticide 
exposure assessment can be found at http://www.epa.gov/oppefed1/models/
water/index.htm.
    Based on the First Index Reservoir Screening Tool (FIRST), 
Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/
EXAMS) and Screening Concentration in Ground Water (SCI-GROW) models, 
the estimated drinking water concentrations (EDWCs) of iodosulfuron-
methyl-sodium for acute exposures are estimated to be 0.60 parts per 
billion (ppb) for surface water and 0.00004 ppb for ground water. For 
chronic exposures for non-cancer assessments are estimated to be 0.067 
ppb for surface water and 0.00004 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For acute dietary risk 
assessment, the water concentration value of 0.60 ppb was used to 
assess the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 0.067 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).
    Iodosulfuron-methyl-sodium is currently registered for the 
following uses that could result in residential exposures: Ornamental 
turf. EPA assessed residential exposure using the following 
assumptions: As the ornamental turf use is labeled ``intended for 
professional use,'' and therefore is not available for direct 
residential use, a residential handler assessment was not conducted. 
All applications for the turf use are to be performed by professional 
(commercial) applicators. The ornamental turf product is intended for 
use on ornamental turfgrass on golf courses, sports fields, commercial 
lawns, cemeteries, parks, campsites, recreational areas, home lawns, 
roadsides, school grounds and sodfarms. Based on this use pattern, 
short and intermediate term risk was assessed.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    EPA has not found iodosulfuron-methyl-sodium to share a common 
mechanism of toxicity with any other substances, and iodosulfuron-
methyl-sodium does not appear to produce a toxic metabolite produced by 
other substances. For the purposes of this tolerance action, therefore, 
EPA has assumed that iodosulfuron-methyl-sodium does not have a common 
mechanism of toxicity with other substances. For information regarding 
EPA's efforts to determine which chemicals have a common mechanism of 
toxicity and to evaluate the cumulative effects of such chemicals, see 
EPA's website at http://www.epa.gov/pesticides/cumulative.

D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(c) of FFDCA provides that EPA 
shall apply an additional tenfold (10X) margin of safety for infants 
and children in the case of threshold effects to account for prenatal 
and postnatal toxicity and the completeness of the database on toxicity 
and exposure unless EPA determines based on reliable data that a 
different margin of safety will be safe for infants and children. This 
additional margin of safety is commonly referred to as the FQPA safety 
factor (SF). In applying 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. There is qualitative 
evidence of increased susceptibility based on the rat developmental 
study where delayed ossification was observed in the fetuses of dams 
that exhibited minimal maternal toxicity (salivation). Similarly, there 
is qualitative and quantitative evidence of increased susceptibility 
based on the multi-generation rat reproduction study where no parental 
systemic effects were observed at the highest dose tested (HDT) and 
offspring toxicity was observed at a lower dose. Susceptibility was not 
observed in the developmental toxicity study in the rabbit.
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA SF were reduced to 1X. That decision is based on the following 
findings:
    i. The toxicity database for iodosulfuron-methyl-sodium is 
complete, except for the requirements for an immunotoxicity, acute, and 
subchronic neurotoxicity studies. The existing data are sufficient for 
endpoint selection for exposure/risk assessment scenarios and for 
evaluation of the requirements under FQPA. EPA has determined that an 
additional uncertainty factor is not required to account for potential 
neurotoxicity or immunotoxicity. The reasons for this determination are 
described as follows:
    a. The toxicity database for iodosulfuron-methyl-sodium is 
complete, except for immunotoxicity testing. EPA began requiring 
functional immunotoxicity testing of all food and non-food use 
pesticides on December 26, 2007. Since this requirement went into 
effect well after the tolerance petition was submitted, these studies 
are not yet available for iodosulfuron-methyl-sodium.

[[Page 23643]]

    In the absence of specific immunotoxicity studies, EPA has 
evaluated the available iodosulfuron-methyl-sodium toxicity data to 
determine whether an additional database uncertainty factor is needed 
to account for potential immunotoxicity. In the case of iodosulfuron-
methyl-sodium, the available data do not indicate a concern for 
potential immunotoxicity. No treatment-related changes were seen in 
hematology parameters, organ weights (thymus, spleen), gross necropsy 
(enlarged lymph nodes) or histopathology (spleen, thymus, lymph nodes) 
when tested up to and including the limit dose (1000 mg/kg/day) in mice 
or rats. Marginal effects, manifested as histopathological changes in 
the bone marrow and spleen, were seen in female dogs. Minimal to 
moderate hyperplasia of the hematopoietic cells was seen in the one 
female. No treatment-related changes were seen in male dogs. The 
subcapsular congestion in the spleen is a common finding and is 
probably related to the means of euthanasia since barbiturates can 
cause the splenic musculature to relax and often leads to blood filled 
spleens. Therefore, the lesions of the spleen are not evidence of 
immunotoxicity. In the absence of corroborative changes in any 
hematology parameters, weights of thymus, spleen and lymph nodes, or 
histopathological changes in the thymus and lymph nodes in the dogs, 
the changes observed are considered hematopoietic, not immunotoxic. 
Therefore an additional uncertainty factor is not needed to account for 
potential immunotoxicity.
    b. Acute and subchronic neurotoxicity testing is also required as a 
result of changes made to pesticide data requirements in December 2007. 
Although acute and subchronic neurotoxicity testing has not yet been 
submitted, iodosulfuron-methyl-sodium does not belong to a class 
chemical that would be expected to be neurotoxic. There is no evidence 
of neurotoxicity in the data base in any species at any dose level. In 
the 90-day dietary studies with mice and rats, there were no signs 
indicative of neurotoxicity when tested at the limit dose (1000 mg/kg/
day). In both species, the LOAEL was based on decreases in body weight 
and/or body weight gain. These findings indicate that the prospective 
neurotoxicity studies will have to be tested at the Limit Dose and even 
with the enhanced evaluation of neurotoxic parameters; these studies 
will not yield a lower dose for risk assessment. Therefore, a database 
uncertainty factor is not required.
     ii. While there is qualitative evidence of increased 
susceptibility based on the rat developmental study, the developmental 
toxicity manifested as delayed ossification (which are variations not 
malformations) were seen only at the limit dose in the presence of 
maternal toxicity, and with a clear NOAEL for the effect of concern. 
Susceptibility was not observed in the developmental toxicity study in 
the rabbit. Additionally no parental systemic effects were observed at 
the limit dose and offspring toxicity was observed at a lower dose 
(34.2 mg/kg/day; manifested as decreased pup viability on post-natal 
day (PND) 0 and 4) in the multi-generation rat reproduction study. In 
spite of the lack of parental toxicity, there was a well characterized 
NOAEL/LOAEL for offspring toxicity; the developmental NOAEL is used for 
the acute dietary risk assessment; and the NOAEL (7.3 mg/kg/day) used 
for the chronic dietary risk assessment is approximately 47-fold lower 
than the offspring NOAEL (346 mg/kg/day). Therefore, there is low 
concern for increased susceptibility for iodosulfuron-methyl-sodium and 
no additional uncertainty factor is needed.
    iii. There are no residual uncertainties identified in the exposure 
databases. The dietary food exposure assessments were performed based 
on 100 PCT and tolerance-level residues. EPA made conservative 
(protective) assumptions in the ground and surface water modeling used 
to assess exposure to iodosulfuron-methyl-sodium in drinking water. EPA 
used similarly conservative assumptions to assess postapplication 
exposure of children as well as incidental oral exposure of toddlers. 
These assessments will not underestimate the exposure and risks posed 
by iodosulfuron-methyl-sodium.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic pesticide exposures are 
safe by comparing aggregate exposure estimates to the aPAD and cPAD. 
The aPAD and cPAD represent the highest safe exposures, taking into 
account all appropriate SFs. EPA calculates the aPAD and cPAD by 
dividing the POD by all applicable UFs. For linear cancer risks, EPA 
calculates the probability of additional cancer cases 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 POD to ensure that the MOE called for 
by the product of all applicable UFs is not exceeded.
    1. Acute risk. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from food and water 
to iodosulfuron-methyl-sodium will occupy <1.0 % of the aPAD for (all 
infants (<1 year old)) the population group receiving the greatest 
exposure.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
iodosulfuron-methyl-sodium from food and water will utilize 3.1% of the 
cPAD for (children 3-5 years old) the population group receiving the 
greatest exposure. Based on the explanation in Unit III.C.3., regarding 
residential use patterns, chronic residential exposure to residues of 
iodosulfuron-methyl-sodium is not expected.
    3. Short-term risk. 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).
    Iodosulfuron-methyl-sodium is currently registered for use that 
could result in short-term residential exposure and the Agency has 
determined that it is appropriate to aggregate chronic exposure through 
food and water with short-term residential exposures to iodosulfuron-
methyl-sodium.
    Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded the combined short-term food, water, 
and residential exposures aggregated result in aggregate MOEs of 
110,000 for children 3-5 years old and 420,000 for adults 20-49 years 
old.
    4. 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).
    Iodosulfuron-methyl-sodium is currently registered for use that 
could result in intermediate-term residential exposure and the Agency 
has determined that it is appropriate to aggregate chronic exposure to 
iodosulfuron-methyl-sodium through food and water with intermediate-
term exposures for iodosulfuron-methyl-sodium.
    Using the exposure assumptions described in this unit for 
intermediate-term exposures, EPA has concluded that the combined 
intermediate-term food, water, and residential exposures aggregated 
result in aggregate MOEs of 21,000 for children 3-5 years old, and 
84,000 for adults 20-49 years old.

[[Page 23644]]

    5. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence for carcinogenicity in mice and rats, iodosulfuron-methyl-
sodium is not expected to pose a cancer risk.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, or to infants and children from aggregate 
exposure to iodosulfuron-methyl-sodium residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology (liquid chromatography using mass 
spectrometric detection (LC/MS/MS) and by high performance liquid 
chromatography with ultra violet detection (HPLC/UV)) is available to 
enforce the tolerance expression. 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; 
e-mail address: residuemethods@epa.gov.

B. International Residue Limits

    There are no Codex MRLs for residues of iodosulfuron-methyl-sodium, 
and no Mexican MRLs have been established. Canadian MRLs have been 
established for certain residues of iodosulfuron-methyl-sodium; 
however, no MRLs have been established for wheat commodities at this 
time.

C. Revisions to Petitioned-For Tolerances

    Review of available field trial data indicate that the proposed 
tolerance for wheat, forage (0.06 ppm) is too low; a tolerance of 0.10 
ppm is appropriate based on the maximum residue limit (MRL) observed 
in/on forage.

V. Conclusion

    Therefore, tolerances are established for residues of iodosulfuron-
methyl-sodium, methyl 4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5 triazin-2-
yl) ureidosulfonyl] benzoate, sodium salt, in or on wheat, forage at 
0.10 ppm; wheat, grain at 0.02 parts per million (ppm); wheat, hay at 
0.05 ppm; and wheat, straw at 0.05 ppm.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this 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 section 408(d) of FFDCA, such as the tolerance in 
this final rule, do not require the issuance of a proposed rule, the 
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et 
seq.) do not apply.
    This final rule directly regulates growers, food processors, food 
handlers, and food retailers, not States or tribes, nor does this 
action alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. As such, the Agency has determined that 
this action will not have a substantial direct effect on States or 
tribal governments, on the relationship between the national government 
and the States or tribal governments, or on the distribution of power 
and responsibilities among the various levels of government or between 
the Federal Government and Indian tribes. Thus, the Agency has 
determined that Executive Order 13132, entitled Federalism (64 FR 
43255, August 10, 1999) and Executive Order 13175, entitled 
Consultation and Coordination with Indian Tribal Governments (65 FR 
67249, November 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) (Public Law 104-4).
    This action does not involve any technical standards that would 
require Agency consideration of voluntary consensus standards pursuant 
to section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272 
note).

VII. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report to each House of the Congress and to 
the Comptroller General of the United States. EPA will submit a report 
containing this rule and other required information to the U.S. Senate, 
the U.S. House of Representatives, and the Comptroller General of the 
United States prior to publication of this final rule in the Federal 
Register. This final rule is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

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

    Dated: May 11, 2009.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

0
Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

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

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

0
2. Section 180.580 is amended by alphabetically adding the following 
commodities to the table in paragraph (a) to read as follows:

Sec.  180.580  Iodosulfuron-methyl-sodium; tolerances for residues.

    (a) * * *

------------------------------------------------------------------------
                      Commodity                        Parts per million
------------------------------------------------------------------------

                              * * * * * * *
Wheat, forage........................................               0.10
Wheat, grain.........................................               0.02
Wheat, hay...........................................               0.05

[[Page 23645]]

Wheat, straw.........................................               0.05
------------------------------------------------------------------------

* * * * *

[FR Doc. E9-11633 Filed 5-19-09; 8:45 am]

BILLING CODE 6560-50-S