Source: https://www.federalregister.gov/documents/2007/08/15/E7-16050/lambda-cyhalothrin-pesticide-tolerance
Timestamp: 2017-09-20 22:16:45
Document Index: 217549140

Matched Legal Cases: ['art 178', 'art 178', 'art 180', 'art 178', 'art 178', 'art 178', 'art 2']

A Rule by the Environmental Protection Agency on 08/15/2007
This regulation is effective August 15, 2007. Objections and requests for hearings must be received on or before October 15, 2007, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
72 FR 45656
45656-45663 (8 pages)
EPA-HQ-OPP-2005-0545
FRL-8143-1
E7-16050
https://www.federalregister.gov/d/E7-16050 https://www.federalregister.gov/d/E7-16050
This regulation establishes tolerances for the combined residues of lambda-cyhalothrin, 1:1 mixture of (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 R,3 R)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and its epimer expressed as epimer of lambda-cyhalothrin, a 1:1 mixture of (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 R,3 R)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate in or on cucurbit vegetables (Group 9), tuberous and corm vegetables (Subgroup 1C), grass (forage, fodder, and hay) (Group 17), barley, buckwheat, oat, rye, wild rice, and pistachios. Syngenta Crop Protection, Inc. and the Interregional Project No. 4 (IR-4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
This regulation is effective August 15, 2007. Objections and requests for hearings must be received on or before October 15, 2007, and must be filed in accordance with the Start Printed Page 45657instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
EPA has established a docket for this action under docket identification (ID) number EPA-HQ-OPP-2005-0545. To access the electronic docket, go to http://www.regulations.gov, select “Advanced Search,” then “Docket Search.” Insert the docket ID number where indicated and select the “Submit” button. Follow the instructions on the regulations.gov website to view the docket index or access available documents. All documents in the docket are listed in the docket index available in regulations.gov. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available in the electronic docket at 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.
Bonaventure Akinlosotu, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone number: (703) 605-0653; e-mail address: akinlosotu.bonaventure@epa.gov.
In addition to accessing an electronic copy of this Federal Register document through the electronic docket 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 40 CFR part 180 through the Government Printing Office’s pilot e-CFR site at http://www.gpoaccess.gov/​ecfr.
Under section 408(g) of FFDCA, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-2005-0545 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 October 15, 2007.
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-2005-0545, by one of the following methods:
In the Federal Register of April 14, 2006 (71 FR 19509) (FRL-7771-7), 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 5F6994) by Syngenta Crop Protection, Inc., 410 Swing Rd., Greensboro, NC 27409 and IR-4, 681 U.S. Highway #1 South, North Brunswick, NJ 08902-3390. The petition requested that 40 CFR 180.438 be amended by establishing a tolerance for combined residues of the insecticide lambda-cyhalothrin, (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 R,3 R)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and the epimer of lambda-cyhalothrin, (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate in or on food commodity crop groupings: Cucurbit vegetables (Crop Group 9) at 0.05 parts per million (ppm); grass, forage, fodder, hay (Crop Group 17) at 9.0 ppm; tuberous and corm vegetables (Crop Subgroup 1-C) at 0.01 ppm; barley, buckwheat, oat, rye, grain at 0.05 ppm; barley, bran at 0.2 ppm; oat, rye, forage at 2.0 ppm; barley, oat, hay at 2.0 ppm; barley, oat, rye, straw at 2.0ppm; and wild rice, grain at 1.0 ppm. That notice referenced a summary of the petition prepared by Syngenta Crop Protection, Inc., the registrant, which is available to the public in the docket, http://www.regulations.gov. No Start Printed Page 45658comments were received on the notice of filing.
The April 14, 2006 notice announcing the pesticide petition from Syngenta Crop Protection, Inc. and IR-4 inadvertently left out the PP number for the IR-4 petition though the commodities IR-4 requested were proposed. There are actually two petitions (PP 3E6593 and PP 5F6994). PP 3E6593 submitted by IR-4 requested that 40 CFR 180.438 be amended by establishing a tolerance for combined residues of the insecticide lambda-cyhalothrin and its epimer in or on food commodities: Barley, buckwheat, oat, rye, grain at 0.05 ppm; barley, bran at 0.2 ppm; oat, rye, forage at 2.0 ppm; barley, oat, hay at 2.0 ppm; barley, oat, rye, straw at 2.0 ppm; and wild rice, grain at 1.0 ppm. PP 5F6994 submitted by Syngenta Crop Protection, Inc., requested that 40 CFR 180.438 be amended by establishing a tolerance for combined residues of the insecticide lambda-cyhalothrin and its epimer in or on food commodity crop groupings: Cucurbit vegetables (Crop Group 9) at 0.05 ppm; grass, forage, fodder, hay (Crop Group 17) at 9.0 ppm; tuberous and corm vegetables (Crop Subgroup 1-C) at 0.01 ppm.
In the Federal Register of October 11, 2006 (71 FR 59780) (FRL-8097-5), 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 6E7077) by Syngenta Crop Protection, Inc., P.O. Box 18300, Greensboro, NC 27419-8300. The petition requested that 40 CFR 180.438 be amended by establishing a tolerance for the combined residues of the insecticide lambda-cyhalothrin in or on pistachio at 0.05 ppm. That notice referenced a summary of the petition prepared by Syngenta Crop Protection, Inc., 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.
Consistent with FFDCA section 408(b)(2)(D), and the factors specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available scientific data and other relevant information in support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure for the petitioned-for tolerance for the combined residues of lambda-cyhalothrin in or on cucurbit vegetables (Crop Group 9) at 0.05 ppm; grass, forage, fodder and hay (Crop Group 17) at 7.0 ppm; tuberous and corm vegetables (Crop Subgroup 1C) at 0.02 ppm; barley, grain at 0.05 ppm; buckwheat, grain at 0.05 ppm; oat, grain at 0.05 ppm; rye, grain at 0.05 ppm; barley, bran at 0.2 ppm; rye, bran at 0.2 ppm; oat, forage at 2.0 ppm; rye, forage at 2.0 ppm; barley, hay at 2.0 ppm; oat, hay at 2.0 ppm; barley, straw at 2.0 ppm; oat, straw at 2.0 ppm; rye, straw at 2.0 ppm; rice, wild, grain at 1.0 ppm; pistachio at 0.05 ppm; hog, fat at 0.2 ppm; hog, meat at 0.01 ppm; hog, meat-byproducts at 0.02 ppm; and milk, fat at 10.0 ppm (reflecting 0.4 ppm in whole milk). EPA's assessment of exposures and risks associated with establishing the tolerance follows.
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 lambda-cyhalothrin as well as the no-observed-adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-level (LOAEL) from the toxicity studies are discussed in the final rule published in the Federal Register of April 8, 2004 (69 FR 18480) (FRL-7353-4).
For hazards that have a threshold below which there is no appreciable risk, the toxicological level of concern (LOC) is derived from the highest dose at which no adverse effects are observed (the NOAEL) in the toxicology study identified as appropriate for use in risk assessment. However, if a NOAEL cannot be determined, the lowest dose at which adverse effects of concern are identified (the LOAEL) is sometimes used for risk assessment. Uncertainty/safety factors (UF) are used in conjunction with the LOC to take into account uncertainties inherent in the extrapolation from laboratory animal data to humans and in the variations in sensitivity among members of the human population as well as other unknowns. Safety is assessed for acute and chronic risks by comparing aggregate exposure to the pesticide to the acute population adjusted dose (aPAD) and chronic population adjusted dose (cPAD). The aPAD and cPAD are calculated by dividing the LOC by all applicable UFs. Short-, intermediate-, and long-term risks are evaluated by comparing aggregate exposure to the LOC to ensure that the margin of exposure (MOE) called for by the product of all applicable UFs is not exceeded.
A summary of the toxicological endpoints for lambda-cyhalothrin used for human risk assessment is discussed in Unit III.B. of the final rule published in the Federal Register of April 8, 2004 (69 FR 18480) (FRL-7353-4).
1. Dietary exposure from food and feed uses. In evaluating dietary exposure to lambda-cyhalothrin, EPA considered exposure under the petitioned-for tolerances as well as all existing lambda-cyhalothrin tolerances in (40 CFR 180.438). EPA assessed dietary exposures from lambda-cyhalothrin 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 the Dietary Start Printed Page 45659Exposure Evaluation Model (DEEM-FCID(TM), Version 2.03) which uses food consumption information from the United States Department of Agriculture’s (USDA) 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII). A refined acute probabilistic dietary exposure assessment was performed for lambda-cyhalothrin which included all existing and proposed food uses and drinking water. The acute dietary exposure assessment incorporated processing factors and percent crop treated (PCT) estimates. Acute anticipated residues were derived from USDA’s Pesticide Data Program (PDP) monitoring data, field trial studies, and a market basket survey for beef-fat.
ii. Chronic exposure. In conducting the chronic dietary exposure assessment, EPA used DEEM-FCID(TM), Version 2.03 which uses food consumption information from the USDA’s 1994-1996 and 1998 CSFII. As to residue levels in food, EPA conducted a refined chronic dietary exposure assessment for lambda-cyhalothrin to support all existing and proposed food uses, utilizing a single-point estimate of anticipated residues for food and drinking water. The chronic dietary exposure assessment incorporated processing factors and PCT estimates. Chronic anticipated residues were derived from PDP monitoring data, field trial studies, and a market basket survey for beef-fat.
iii. Cancer. Lambda-cyhalothrin is classified as “not likely to be carcinogenic to humans.” Therefore, there is no cancer risk associated with existing or proposed uses.
PCT estimates of agricultural uses for lambda-cyhalothrin were obtained in the form of a screening-level usage assessment (SLUA), based on data years 1999-2004. Average and maximum values for percent crop treated data were used in the chronic and acute analyses, respectively, for the following commodities with established tolerances: Almonds (5 chronic, 5 acute), Apples (5 chronic, 10 acute), Beans, Green (10 chronic, 20 acute), Broccoli (10 chronic, 20 acute), Cabbage (30 chronic, 45 acute), Canola/Rapeseed (1 chronic, 2.5 acute), Cauliflower (20 chronic, 30 acute), Cherries (5 chronic, 15 acute), Corn (1 chronic, 2.5 acute), Cotton (10 chronic, 10 acute), Dry Beans/Peas (1 chronic, 2.5 acute), Garlic (10 chronic, 30 acute), Lettuce (30 chronic, 45 acute), Onions (50 chronic, 55 acute), Peaches (5 chronic, 10 acute), Peanuts (5 chronic, 10 acute), Pears (15 chronic, 30 acute), Peas, Green (1 chronic, 2.5 acute), Pecans (1 chronic, 5 acute), Peppers (5 chronic, 15 acute), Prunes and Plums (5 chronic, 5 acute), Rice (15 chronic, 30 acute), Sorghum (1 chronic, 2.5 acute), Soybeans (5 chronic, 10 acute), Sugarcane (5 chronic, 10 acute), Sunflowers (10 chronic, 20 acute), Sweet Corn (45 chronic, 60 acute), Tomatoes (20 chronic, 20 acute), and Wheat (1 chronic, 2.5 acute). For all other commodities and for new uses, 100% PCT was assumed. Tolerance level values were used for the following commodities: Okra, eggplant, poultry, tree nuts group (crop group 14) except almonds and pecans, and tuberous and corm vegetables subgroup (crop subgroup 1C) except potatoes.
EPA uses an average PCT for chronic dietary risk analysis. The average PCT figure for each existing use is derived by combining available Federal, State, and private market survey data for that use, averaging by year, averaging across all years, and rounding up to the nearest multiple of 5% except for those situations in which the average PCT is less than one. In those cases <1% is used as the average and <2.5% is used as the maximum. EPA uses a maximum PCT for acute dietary risk analysis. The maximum PCT figure is the single maximum value reported overall from available Federal, State, and private market survey data on the existing use, across all years, and rounded up to the nearest multiple of 5%. 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 Center for Food and Agriculture Policy (NCFAP) for the most recent 6 years.
The Agency believes that the three conditions listed in Unit III.C.1.iv. have been met. With respect to Condition 1, 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 2 and 3, 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 information on the regional consumption of food to which lambda-cyhalothrin may be applied in a particular area.
2. Dietary exposure from drinking water. The Agency lacks sufficient monitoring data to complete a comprehensive dietary exposure analysis and risk assessment for lambda-cyhalothrin in drinking water. Because the Agency does not have comprehensive monitoring data, drinking water concentration estimates are made by reliance on simulation or modeling taking into account data on the environmental fate characteristics of lambda-cyhalothrin. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at Start Printed Page 45660 http://www.epa.gov/​oppefed1/​models/​water/​index.htm.
Based on the First Index Reservoir Screening Tool (FIRST) and Screening Concentrations in Groundwater (SCI-GROW) models, the estimated drinking water concentrations (EDWCs) of lambda-cyhalothrin for acute exposures are estimated to be 5.35 parts per billion (ppb) for surface water and 0.00336 ppb for ground water. The EECs for chronic exposures are estimated to be 0.130 ppb for surface water and 0.00336 ppb for ground water. The EDWCs for lambda-cyhalothrin were calculated based on a maximum application rate of 0.5 pounds active ingredient per acre per season (lb a.i./A/season) for orchards (ground application) for surface and groundwater concentrations. A default percent crop area (PCA) factor of 0.87 (87%) was applied to the orchards scenario. The orchards scenario using the FIRST model produced the highest concentrations.
Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model. For acute dietary risk assessment, the water concentration value of 5.35 ppb was used to assess the contribution to drinking water. For chronic dietary risk assessment, the water concentration of value 0.130 ppb was used to assess the contribution to drinking water.
Lambda-cyhalothrin is currently registered for the following residential non-dietary sites: Ornamental gardens, lawns, landscapes, turf, golf courses, and general insect control (spot treatments, and crack and crevice treatments) in, around, and on buildings, structures, and immediate surroundings. All registered products, except for one aerosol can product, are limited to use only by certified applicators. As such, this assessment ADDRESSES the single-residential handler scenario for aerosol can users, and post-application scenarios associated with any use in a residential environment. Both short-term and intermediate-term exposures are possible.
For the residential assessment, existing uses on turf, in gardens, on golf courses, and for structural pest control were considered, but a quantitative calculation was only completed for post-application exposure on treated turf. The Agency used a conservative screening-level approach to address the risks associated with the use of the aerosol can product of lambda-cyhalothrin that can be purchased and used by homeowners.
A screening-level quantitative calculation was completed for post-application exposure on treated turf only because this scenario is expected to have the highest associated exposures of all residential exposures. EPA believes that the selected post-application assessment on lawns for children is protective for all residential exposures (even the aerosol can handler scenario) because the dose levels for children playing on treated lawns are thought to exceed those expected for all other scenarios (lawn exposures for children represents the worst-case scenario). This approach is based on the following conservative considerations:
i. EPA assumed that children contacted lawns immediately after application of lawn product and thus there was no dissipation of residues from the treated lawn.
ii. EPA estimated dermal exposure based on a high duration of exposure on the lawn and an intensity of activity that results in a high degree of contact with the treated lawn.
iii. EPA assumed that the pesticide was applied at the maximum application rate.
Lambda-cyhalothrin is a member of the pyrethroid class of pesticides. Although all pyrethroids alter nerve function by modifying the normal biochemistry and physiology of nerve membrane sodium channels, EPA is not currently following a cumulative risk approach (based on a common mechanism of toxicity) for the pyrethroids. Although pyrethroids interact with sodium channels, there are multiple types of sodium channels, and it is currently unknown whether pyrethroids have similar effects on all channels. Nor is there a clear understanding of effects on key downstream neuronal function (nerve excitability), nor do we understand how these key events interact to produce their compound specific patterns of neurotoxicity. There is ongoing research by the EPA’s Office of Research and Development (and pyrethroid registrants) to evaluate the differential biochemical and physiological actions of pyrethroids in mammals. When available, the Agency will consider this research, and make a determination of common mechanism as a basis for assessing cumulative risk. 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.
2. The completeness of the database. The toxicology database is considered complete for the purposes of an FQPA risk assessment. Based on the developmental studies in rats and rabbits, and the 3-generation and neurodevelopmental studies in rats, there is no evidence of increased susceptibility. The neurotoxicity observed in adult animal studies raised a concern for potential neurodevelopmental effects. A rat developmental neurotoxicity (DNT) study is available. In this study, the lowest dose showing neurotoxicity in the offspring (effects on mortality, body weights, body weight gains, learning, learning and memory, and brain morphometry) is 10 milligram/kilogram body weight/day (mg/kg bw/day), with a NOAEL of 4 mg/kg bw/day. Effects in offspring and adult animals are found at a similar dose based on body weight decreases. It should be noted that some of the parameters evaluated in this DNT study were regarded as acceptable but several others were not, leading to a study classification of “unacceptable.” The study deficiencies which, taken together, led to the unacceptable classification include:
i. Statistical analyses that adjusted for body weights after treatment had begun.Start Printed Page 45661
ii. An inadequate assessment of motor activity.
iii. An inadequate assessment of auditory startle in postnal day (PND) 61 females.
iv. Missing low- and mid-dose morphometry data.
However, it is not likely that these limitations will impact the risk assessment for the following reasons. The slight changes in brain morphometry were seen at the highest dose tested. Because these changes were slight, it is uncertain whether toxicologically significant differences would be seen at the mid dose, and it is unlikely that significant changes would be seen at the lowest dose tested. The auditory startle response is considered adequate for assessment in PND 23 males/females and PND 61 males where no treatment-related effects were seen in auditory startle response. Only the auditory response data for PND 61 females is inadequate. Motor activity was examined and there did not appear to be any differences between treated and control animals other than decreases for multiple subsessions in PND 18 males/females at the high dose only, but due to the high variability and the lack of habituation, these data are considered equivocal. There was no published literature found that would indicate a neurodevelopmental concern for lambda-cyhalothrin.
The exposure assessments are based on reliable data and reasonable worst-case assumptions, and are not likely to underestimate exposure. Reliable data on anticipated dietary residues was relied upon including crop field trial studies and monitoring data. Conservative ground and surface water modeling estimates were used. Similarly, conservative Residential Standard Operating Procedures were used to assess post-application exposure to children as well as incidental oral exposure of toddlers. These assessments will not underestimate the exposure and risks posed by lambda-cyhalothrin.
3. Prenatal and postnatal sensitivity. No quantitative or qualitative evidence of increased susceptibility of rat or rabbit fetuses to in utero exposure in the developmental studies was observed. No developmental toxicity was observed in either of these studies. No quantitative or qualitative evidence of increased susceptibility was observed in the 3-generation reproduction study in rats. Offspring toxicity (decreased pup weight and pup weight gain) was observed in the reproduction study at the same dose level as parental toxicity (decreased body weight and body weight gain). These effects are not considered to be more severe than the effects in the parents.
EPA has received a DNT for lambda-cyhalothrin (Master Record Identification Number 46449102), which was classified as unacceptable/guideline due to inadequacies in some of the developmental parameters tested. Nonetheless, for the reasons noted in Unit VII.D.2., EPA does not believe that correction of the deficiencies in this study would meaningfully change its evaluation of the risk posed by lambda-cyhalothrin and is not requiring that the study be repeated. In any event, if a 10-fold factor is applied to this study’s NOAEL, (i.e., 4 mg/kg bw/day) to account for the scientific limitations of the study, the resulting value is 0.4 mg/kg bw/day. This estimate of 0.4 mg/kg/day is similar to the doses from the chronic dog study used for risk assessment (i.e., 0.5 mg/kg/day for acute dietary exposure scenarios and 0.1 mg/kg/day for chronic dietary exposure scenarios). Therefore, EPA concludes that using the NOAELs from the dog study would not underestimate risks to infants and children from exposure to lambda-cyhalothrin, and consequently, a repeat rat DNT study is not required.
4. Conclusion. EPA has determined that reliable data show that it would be safe for infants and children to reduce the FQPA safety factor to 1X. That decision is based on the following findings:
i. The toxicity database for lambda-cyhalothrin is considered complete for the purpose of an FQPA assessment.
ii. All doses and endpoints for risk assessment are based on neurotoxic effects seen in the dog, widely known as the most sensitive test species for pyrethroids.
iii. There is no evidence that lambda-cyhalothrin results in increased susceptibility in in utero rats or rabbits in the prenatal developmental studies or in young rats in the 2-generation reproduction study. The acceptable parameters of the developmental neurotoxicity study in rats do not indicate increased susceptibility to pups exposed in utero.
iv. The exposure assessments are based on reliable data and reasonable worst-case assumptions, and are not likely to underestimate exposure.
Based on all of the considerations in Unit III.D.3., there is not a need to retain the additional 10X safety factor for children. Application of the 10X intraspecies uncertainty factor (which accounts for the possibility that a subpopulation may be 10 times more sensitive than the average individual) and a 10X interspecies factor (which accounts for the possibility that humans may be 10 times more sensitive than animals) to the dog NOAEL (i.e., the most sensitive species) should assure protection of human health including children. Therefore, EPA has determined that reliable data show that it would be safe for infants and children to reduce the FQPA safety factor to 1X.
1. Acute risk. Using the exposure assumptions discussed in this unit for acute exposure, the acute dietary exposure from food and water to lambda-cyhalothrin will occupy 46% of the aPAD for the general U.S. population, and 61% of the aPAD for all infants (<1 year old), the most highly exposed population subgroup.
2. Chronic risk. Using the exposure assumptions described in this unit for chronic exposure, EPA has concluded that exposure to lambda-cyhalothrin from food and water will utilize 17% of the cPAD for the general U.S. population, and 50% of the cPAD for children (1-2 years old), the most highly exposed population subgroup. Based on the use pattern, chronic residential exposure to residues of lambda-cyhalothrin is not expected.
Lambda-cyhalothrin is currently registered for use that could result in short-term and intermediate-term residential exposure and the Agency has determined that it is appropriate to aggregate chronic food and water and short-term exposures for lambda-cyhalothrin.
Using the exposure assumptions described in this unit for short-term and intermediate-term exposures, EPA has concluded that food, water, and residential exposures aggregated result in aggregate MOEs of 140 to 490. The residential MOEs were aggregated together because, regardless of the exposure route (dermal, inhalation, or Start Printed Page 45662oral), lambda-cyhalothrin has similar adverse effects (neurotoxicity). This aggregate risk assessment incorporates lawn post-application exposure (the scenario with the highest potential for exposure), and is a day-0 screening-level assessment. The resulting aggregate MOEs were greater than the Agency target MOE of 100 (ranging from 140 to 490), and there were thus no concerns for aggregate exposure.
4. Aggregate cancer risk for U.S. population. Lambda-cyhalothrin is classified as “not likely to be carcinogenic to humans.” Therefore, there is no aggregate cancer risk associated with the existing or proposed uses.
5. 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 lambda-cyhalothrin residues.
Adequate enforcement methodology (gas chromatography/electron capture detector (GC/ECD) methods are available for enforcing tolerances for lambda-cyhalothrin residues in plant and animal commodities. 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.
The Codex Alimentarius Commission, Mexico, and Canada have all established maximum residue limits (MRLs) for residues of lambda-cyhalothrin in or on a variety of raw agricultural commodities. These regulatory bodies express residues in terms of only cyhalothrin (Codex) or of lambda-cyhalothrin (Canada, Mexico); none of these tolerances include the epimer R157836 found in the U.S. tolerance expression. EPA includes the epimer due to it being considered as toxic as the active ingredient and its presence at quantifiable levels in many crops. For the crop uses currently under consideration, only potatoes have existing international tolerances. Although the recommended 0.02 ppm U.S. tolerance agrees numerically with the Codex and Mexican MRLs, strictly speaking they are not in harmony due to the different residue definitions.
Several comments were received from a private citizen objecting to IR-4 petitioning for tolerances, pesticide residues on food and the establishment of these tolerances. The Agency has received similar comments from this commenter on numerous previous occasions. Refer to the Federal Registers of June 30, 2005 (70 FR 37686) (FRL-7718-3), January 7, 2005 (70 FR 1354) (FRL-7691-4), and October 29, 2004 (69 FR 63096-63098) (FRL-7681-9) for the Agency’s response to these objections. In addition, the commenter noted several adverse effects seen in animal toxicology studies with lambda-cyhalothrin and claims because of these effects no tolerance should be approved. EPA has found, however, that there is a reasonable certainty of no harm to humans after considering these toxicological studies and the exposure levels of humans to lambda-cyhalothrin. The commenter also identified potential effects on the environment. This comment is considered irrelevant because the safety standard for approving tolerances under section 408 of FFDCA focuses on potential harms to human health and does not permit consideration of effects on the environment. Effects on the environment were considered by EPA in the registration process for lambda-cyhalothrin under the Federal Insecticide, Fungicide, and Rodenticide Act, 7 U.S.C. 136 et seq.
Modifications to the pesticide petitions included in this final rule include: Grass, (forage, fodder, hay) from 9.0 ppm to 7.0 ppm because a crop group tolerance is appropriate—grass forage, fodder, and hay (Group 17); rye, bran at 0.2 ppm based on the existing residue data and tolerances in similar wheat commodities; hog, fat from 3.0 ppm to 0.2 ppm, hog, meat from 0.2 ppm to 0.01 ppm, hog, and meat-byproducts from 0.2 ppm to 0.02 ppm based on a Theoretical Dietary Burden (TDB) of 0.9 ppm for swine, the maximum expected residues are 0.16 ppm in hog fat, 0.006 ppm in hog meat, and 0.011 ppm in hog meat-byproducts; and milk, fat from 5.0 ppm to 10.0 ppm based on a TDB of 10.4 ppm for dairy cattle, the maximum expected residues in milk are 0.35 ppm, equivalent to 8.8 ppm in milk fat.
Therefore, the tolerances are established for the combined residues of lambda-cyhalothrin, 1:1 mixture of (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 R,3 R)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and its epimer expressed as epimer of lambda-cyhalothrin, a 1:1 mixture of (S)-α-cyano-3-phenoxybenzyl-(Z)-(1 S,3 S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate and (R)-α-cyano-3-phenoxybenzyl-(Z)-(1 R,3 R)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate, in or on cucurbit vegetables (Crop Group 9) at 0.05 ppm; grass, forage, fodder and hay (Crop Group 17) at 7.0 ppm; tuberous and corm vegetables (Crop Subgroup 1C) at 0.02 ppm; barley, grain at 0.05 ppm; buckwheat, grain at 0.05 ppm; oat, grain at 0.05 ppm; rye, grain at 0.05 ppm; barley, bran at 0.2 ppm; rye, bran at 0.2 ppm; oat, forage at 2.0 ppm; rye, forage at 2.0 ppm; barley, hay at 2.0 ppm; oat, hay at 2.0 ppm; barley, straw at 2.0 ppm; oat, straw at 2.0 ppm; rye, straw at 2.0 ppm; rice, wild, grain at 1.0 ppm; pistachio at 0.05 ppm; hog, fat at 0.2 ppm; hog, meat at 0.01 ppm; hog, meat-byproducts at 0.02 ppm; and milk, fat at 10.0 ppm (reflecting 0.4 ppm in whole milk).
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.Start Printed Page 45663
2. Section 180.438 is amended by:
i. Revising the entries “hog, fat;” “hog, meat;” “hog, meat byproducts;” and “milk, fat (reflecting 0.4 ppm in whole milk)” in the table in paragraph (a) (1).
ii. Adding alphabetically the following commodities to the table in paragraph (a)(1) to read as follows:
Barley, bran 0.2
Barley, hay 2.0
Barley, straw 2.0
Buckwheat, grain 0.05
Grass, forage, fodder and hay, group 17 7.0
Milk, fat (reflecting 0.4 ppm in whole milk) 10.0
Oat, grain 0.05
Oat, forage 2.0
Oat, hay 2.0
Oat, straw 2.0
Rice, wild, grain 1.0
Rye, bran 0.2
Rye, grain 0.05
Rye, forage 2.0
Rye, straw 2.0
Vegetable, cucurbit, group 9 0.05
Vegetable, tuberous and corm, subgroup 1C 0.02
[FR Doc. E7-16050 Filed 8-14-07; 8:45 am]