Dicamba; Pesticide Tolerance, 17914-17918 [E8-6674]

Download as PDF 17914 Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations [FR Doc. E8–6818 Filed 4–1–08; 8:45 am] FOR FURTHER INFORMATION CONTACT: BILLING CODE 6560–50–S 40 CFR Part 180 Susan Stanton, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460–0001; telephone number: (703) 305–5218; e-mail address: stanton.susan@epa.gov. [EPA–HQ–OPP–2007–0325; FRL–8356–6] SUPPLEMENTARY INFORMATION: Dicamba; Pesticide Tolerance I. General Information Environmental Protection Agency (EPA). ACTION: Final rule. A. Does this Action Apply to Me? ENVIRONMENTAL PROTECTION AGENCY mstockstill on PROD1PC66 with RULES AGENCY: SUMMARY: This regulation establishes tolerances for combined residues of dicamba and its 5-hydroxy metabolite in or on corn, sweet, forage; corn, sweet, kernel plus cob with husks removed; and corn, sweet, stover. Interregional Research Project Number 4 (IR-4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA). DATES: This regulation is effective April 2, 2008. Objections and requests for hearings must be received on or before June 2, 2008, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION ). ADDRESSES: EPA has established a docket for this action under docket identification (ID) number EPA–HQ– OPP–2007–0325. To access the electronic docket, go to https:// www.regulations.gov, select ‘‘Advanced Search,’’ then ‘‘Docket Search.’’ Insert the docket ID number where indicated and select the ‘‘Submit’’ button. Follow the instructions on the regulations.gov website to view the docket index or access available documents. All documents in the docket are listed in the docket index available in regulations.gov. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available in the electronic docket at https://www.regulations.gov, or, if only available in hard copy, at the OPP Regulatory Public Docket in Rm. S– 4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The Docket Facility telephone number is (703) 305– 5805. VerDate Aug<31>2005 18:23 Apr 01, 2008 Jkt 214001 You may be potentially affected by this action if you are an agricultural producer, food manufacturer, or pesticide manufacturer. Potentially affected entities may include, but are not limited to those engaged in the following activities: • Crop production (NAICS code 111), e.g., agricultural workers; greenhouse, nursery, and floriculture workers; farmers. • Animal production (NAICS code 112), e.g., cattle ranchers and farmers, dairy cattle farmers, livestock farmers. • Food manufacturing (NAICS code 311), e.g., agricultural workers; farmers; greenhouse, nursery, and floriculture workers; ranchers; pesticide applicators. • Pesticide manufacturing (NAICS code 32532), e.g., agricultural workers; commercial applicators; farmers; greenhouse, nursery, and floriculture workers; residential users. This listing is not intended to be exhaustive, but rather to provide a guide for readers regarding entities likely to be affected by this action. Other types of entities not listed in this unit could also be affected. The North American Industrial Classification System (NAICS) codes have been provided to assist you and others in determining whether this action might apply to certain entities. If you have any questions regarding the applicability of this action to a particular entity, consult the person listed under FOR FURTHER INFORMATION CONTACT. B. How Can I Access Electronic Copies of this Document? In addition to accessing an electronic copy of this Federal Register document through the electronic docket at https:// www.regulations.gov, you may access this Federal Register document electronically through the EPA Internet under the ‘‘Federal Register’’ listings at https://www.epa.gov/fedrgstr. You may also access a frequently updated electronic version of EPA’s tolerance regulations at 40 CFR part 180 through the Government Printing Office’s pilot e-CFR site at https://www.gpoaccess.gov/ ecfr. PO 00000 Frm 00034 Fmt 4700 Sfmt 4700 C. Can I File an Objection or Hearing Request? Under section 408(g) of FFDCA, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA–HQ– OPP–2007–0325 in the subject line on the first page of your submission. All requests must be in writing, and must be mailed or delivered to the Hearing Clerk as required by 40 CFR part 178 on or before June 2, 2008. In addition to filing an objection or hearing request with the Hearing Clerk as described in 40 CFR part 178, please submit a copy of the filing that does not contain any CBI for inclusion in the public docket that is described in ADDRESSES. Information not marked confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without prior notice. Submit this copy, identified by docket ID number EPA– HQ–OPP–2007–0325, by one of the following methods: • Federal eRulemaking Portal: https://www.regulations.gov. Follow the on-line instructions for submitting comments. • Mail: Office of Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460–0001. • Delivery: OPP Regulatory Public Docket (7502P), Environmental Protection Agency, Rm. S–4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only accepted during the Docket’s normal hours of operation (8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays). Special arrangements should be made for deliveries of boxed information. The Docket Facility telephone number is (703) 305–5805. II. Petition for Tolerance In the Federal Register of May 9, 2007 (72 FR 26375) (FRL–8128–1), EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition ((PP) 0E6209) by Interregional Research Project Number 4 (IR-4), 500 College Road East, Suite 201 W, Princeton, NJ 08540–6635. The petition requested that 40 CFR 180.227 be amended by establishing tolerances for combined residues of the herbicide dicamba, 3,6-dichloro-o-anisic acid, and E:\FR\FM\02APR1.SGM 02APR1 Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations its metabolite, 3,6-dichloro-5-hydroxy-oanisic acid, in or on corn, sweet, forage at 0.50 parts per million (ppm); corn, sweet, kernel plus cob with husks removed at 0.04 ppm; and corn, sweet, stover at 0.50 ppm. That notice referenced a summary of the petition prepared by BASF Corporation, the registrant, which is available to the public in the docket, https:// www.regulations.gov. There were no comments received in response to the notice of filing. mstockstill on PROD1PC66 with RULES III. Aggregate Risk Assessment and Determination of Safety Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a tolerance (the legal limit for a pesticide chemical residue in or on a food) only if EPA determines that the tolerance is ‘‘safe.’’ Section 408(b)(2)(A)(ii) of FFDCA defines ‘‘safe’’ to mean that ‘‘there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.’’ This includes exposure through drinking water and in residential settings, but does not include occupational exposure. Section 408(b)(2)(C) of FFDCA requires EPA to give special consideration to exposure of infants and children to the pesticide chemical residue in establishing a tolerance and to ‘‘ensure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue....’’ These provisions were added to FFDCA by the Food Quality Protection Act (FQPA) of 1996. Consistent with FFDCA section 408(b)(2)(D), and the factors specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available scientific data and other relevant information in support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure for the petitioned-for tolerances for combined residues of dicamba on corn, sweet, forage at 0.50 ppm; corn, sweet, kernel plus cob with husks removed at 0.04 ppm; and corn, sweet, stover at 0.50 ppm. EPA’s assessment of exposures and risks associated with establishing the tolerance follows. A. Toxicological Profile EPA has evaluated the available toxicity data and considered its validity, completeness, and reliability as well as the relationship of the results of the studies to human risk. EPA has also considered available information concerning the variability of the VerDate Aug<31>2005 18:23 Apr 01, 2008 Jkt 214001 sensitivities of major identifiable subgroups of consumers, including infants and children. Dicamba has low acute toxicity via the oral, dermal and inhalation routes. It is an eye and dermal irritant but it is not a skin sensitizer. Following oral administration, dicamba is rapidly absorbed and excreted in urine and feces. Consistent neurotoxic signs (e.g., ataxia, decreased motor activity, impaired righting reflex and gait) were observed in many studies in rats and rabbits at high doses. Prenatal developmental toxicity studies in rats and rabbits showed no evidence (qualitative or quantitative) of increased susceptibility following in utero or postnatal exposure to dicamba. There was an increased incidence of abortion in the rabbit developmental toxicity study at doses that also showed maternal toxicity. In a 2-generation reproduction study, offspring toxicity was manifested as decreased pup body weight gain in all generations at a dose lower than the parental systemic toxicity NOAEL. Dicamba is classified as ‘‘Not Likely to be Carcinogenic to Humans’’ by the oral route. Mutagenicity studies did not demonstrate evidence of mutagenic potential for dicamba although some positive results were reported in published literature. Specific information on the studies received and the nature of the adverse effects caused by dicamba as well as the no-observed-adverse-effect-level (NOAEL) and the lowest-observedadverse-effect-level (LOAEL) from the toxicity studies can be found at https:// www.regulations.gov in the document Dicamba: Human-Health Risk Assessment for Proposed Section 3 New Uses on Sweet Corn. The referenced document is available in the docket established by this action, which is described under ADDRESSES, and is identified as EPA–HQ–OPP–2007– 0325–0004 in that docket. B. Toxicological Endpoints For hazards that have a threshold below which there is no appreciable risk, the toxicological level of concern (LOC) is derived from the highest dose at which no adverse effects are observed (the NOAEL) in the toxicology study identified as appropriate for use in risk assessment. However, if a NOAEL cannot be determined, the lowest dose at which adverse effects of concern are identified (the LOAEL) is sometimes used for risk assessment. Uncertainty/ safety factors (UFs) are used in conjunction with the LOC to take into account uncertainties inherent in the extrapolation from laboratory animal data to humans and in the variations in PO 00000 Frm 00035 Fmt 4700 Sfmt 4700 17915 sensitivity among members of the human population as well as other unknowns. Safety is assessed for acute and chronic risks by comparing aggregate exposure to the pesticide to the acute population adjusted dose (aPAD) and chronic population adjusted dose (cPAD). The aPAD and cPAD are calculated by dividing the LOC by all applicable UFs. Short-term, intermediate-term, and long-term risks are evaluated by comparing aggregate exposure to the LOC to ensure that the margin of exposure (MOE) called for by the product of all applicable UFs is not exceeded. For non-threshold risks, the Agency assumes that any amount of exposure will lead to some degree of risk and estimates risk in terms of the probability of occurrence of additional adverse cases. Generally, cancer risks are considered non-threshold. For more information on the general principles EPA uses in risk characterization and a complete description of the risk assessment process, see https:// www.epa.gov/fedrgstr/EPA-PEST/1997/ November/Day–26/p30948.htm. A summary of the toxicological endpoints for dicamba used for human risk assessment can be found at https:// www.regulations.gov in the document Dicamba: Human-Health Risk Assessment for Proposed Section 3 New Uses on Sweet Corn. The referenced document is available in the docket established by this action, which is described under ADDRESSES, and is identified as EPA–HQ–OPP–2007– 0325–0004 in that docket. C. Exposure Assessment 1. Dietary exposure from food and feed uses. In evaluating dietary exposure to dicamba, EPA considered exposure under the petitioned-for tolerances as well as all existing dicamba tolerances in 40 CFR 180.227. EPA assessed dietary exposures from dicamba in food as follows: i. Acute exposure. Quantitative acute dietary exposure and risk assessments are performed for a food-use pesticide, if a toxicological study has indicated the possibility of an effect of concern occurring as a result of a 1–day or single exposure. In estimating acute dietary exposure to dicamba, EPA used food consumption information from the U.S. Department of Agriculture (USDA) 1994–1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII). As to residue levels in food, EPA assumed all foods for which there are tolerances were treated and contain tolerance-level residues. No anticipated residues or percent crop E:\FR\FM\02APR1.SGM 02APR1 mstockstill on PROD1PC66 with RULES 17916 Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations treated (PCT) data were used in the acute dietary exposure assessment. ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the food consumption data from the USDA 1994–1996 and 1998 CSFII. As to residue levels in food, EPA assumed all foods for which there are tolerances were treated and contain tolerance-level residues. No anticipated residues or percent crop treated (PCT) data were used in the chronic dietary exposure assessment. iii. Cancer. Based on the results of carcinogenicity studies in rats and mice, EPA has concluded that dicamba is ‘‘not likely to be carcinogenic to humans.’’ Consequently, a quantitative cancer exposure and risk assessment is not appropriate for dicamba. 2. Dietary exposure from drinking water. The residues of concern in drinking water include dicamba and its major degradate, DCSA. The Agency lacks sufficient monitoring data to complete a comprehensive dietary exposure analysis and risk assessment for dicamba and DCSA in drinking water. Because the Agency does not have comprehensive monitoring data, drinking water concentration estimates are made by reliance on simulation or modeling taking into account data on the environmental fate characteristics of dicamba and DCSA. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at https://www.epa.gov/ oppefed1/models/water/index.htm. Based on the Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCIGROW) models, the combined estimated environmental concentrations (EECs) of dicamba and DCSA for acute exposures are estimated to be 367 parts per billion (ppb) for surface water and 0.016 ppb for ground water. The combined EECs for chronic exposures are estimated to be 13.8 ppb for surface water and 0.016 ppb for ground water. Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model. For acute dietary risk assessment, the water concentration value of 367 ppb was used to assess the contribution to drinking water. For chronic dietary risk assessment, the water concentration of value 13.8 ppb was used to assess the contribution to drinking water. 3. From non-dietary exposure. The term ‘‘residential exposure’’ is used in this document to refer to nonoccupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets). VerDate Aug<31>2005 18:23 Apr 01, 2008 Jkt 214001 Dicamba is currently registered for use on residential sites, including home lawns and golf courses. EPA assessed residential exposure using the following assumptions: Residential handlers are likely to be exposed to dicamba residues via dermal and inhalation routes during handling, mixing, loading and applying activities. Based on the current use patterns, EPA expects duration of handler exposure to be short-term (1–30 days). EPA assessed several residential handler scenarios and found that handlers who mix/load and apply dicamba using a hose-end sprayer have the highest estimated exposures. There is also potential for short-term (1–30 days) post-application exposure of adults and children/toddlers on lawns and other turf areas previously treated with dicamba, as well as the potential for acute, episodic exposure of toddlers from ingestion of granules containing dicamba. EPA assessed short-term dermal exposure of adults doing yardwork; short-term dermal and incidental oral exposure of toddlers playing on treated turf; and acute toddler exposure from episodic granule ingestion. Post-application inhalation exposures are expected to be negligible and were, therefore, not assessed. 4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider ‘‘available information’’ concerning the cumulative effects of a particular pesticide’s residues and ‘‘other substances that have a common mechanism of toxicity.’’ Unlike other pesticides for which EPA has followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to dicamba and any other substances and dicamba does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has not assumed that dicamba has a common mechanism of toxicity with other substances. For information regarding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see EPA’s website at https:// www.epa.gov/pesticides/cumulative. D. Safety Factor for Infants and Children 1.In general. Section 408(b)(2)(C) of FFDCA provides that EPA shall apply an additional tenfold (‘‘10X’’) margin of safety for infants and children in the PO 00000 Frm 00036 Fmt 4700 Sfmt 4700 case of threshold effects to account for prenatal and postnatal toxicity and the completeness of the database on toxicity and exposure unless EPA determines based on reliable data that a different margin of safety will be safe for infants and children. This additional margin of safety is commonly referred to as the FQPA safety factor. In applying this provision, EPA either retains the default value of 10X when reliable data do not support the choice of a different factor, or, if reliable data are available, EPA uses a different additional FQPA safety factor value based on the use of traditional UFs and/or special FQPA safety factors, as appropriate. 2. Prenatal and postnatal sensitivity. The prenatal and postnatal toxicology database for dicamba includes rat and rabbit developmental toxicity studies and a 2–generation reproduction toxicity study in rats. There was no evidence (qualitative or quantitative) of increased susceptibility following in utero exposure in the developmental toxicity studies in rats and rabbits. There was evidence of increased sensitivity of the offspring following pre-/postnatal exposure in the 2– generation reproduction study in rats. In that study, offspring toxicity was manifested as decreased pup body weight in all generations at a dose lower than the parental systemic toxicity NOAEL. However, there is low concern and there are no residual uncertainties for the increased susceptibility for the following reasons. The NOAEL of 45 milligrams/kilogram/day (mg/kg) identified in this study was chosen for risk assessments for all routes and exposure durations other than acute oral exposures. Since this NOAEL is the lowest (most sensitive endpoint) in the dicamba toxicity database, and the dose response observed in the study is well defined, assuring that this dose is a clear NOAEL, use of the NOAEL and endpoint for risk assessment is protective for all observed toxic effects of the chemical. The endpoint (decreased pup body weight) is not expected to occur as a result of a single (acute) exposure and was, therefore, not deemed appropriate for assessing acute oral exposures. 3. Conclusion. EPA has determined that reliable data show that it would be safe for infants and children to reduce the FQPA safety factor to 3X for acute oral exposures and to 1X for all other routes and durations of exposure. That decision is based on the following findings: i. The toxicity database for Dicamba is complete. ii. A developmental neurotoxicity study is not required. Consistent E:\FR\FM\02APR1.SGM 02APR1 mstockstill on PROD1PC66 with RULES Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations neurotoxic signs (e.g., ataxia, decreased motor activity, impaired righting reflex and gait) were observed in many studies in rats and rabbits at high doses. After considering the available toxicity data, however, EPA determined that there is no need for a developmental neurotoxicity study or additional UFs to account for neurotoxicity for the following reasons: a. Although clinical signs of neurotoxicity were seen in pregnant animals, no evidence of developmental anomalies of the fetal nervous system were observed in the prenatal developmental toxicity studies, in either rats or rabbits, at maternally toxic doses up to 300 or 400 mg/kg/day, respectively; b. There was no evidence of behavioral or neurological effects on the offspring in the 2–generation reproduction study in rats; and c. The ventricular dilation of the brain in the combined chronic toxicity and carcinogenicity study in rats was only observed in females at the high dose after two years’ exposure. The significance of this observation is questionable, since no similar histopathological finding was seen in the subchronic neurotoxicity study. iii. There is no evidence that dicamba results in increased susceptibility in in utero rats or rabbits in the prenatal developmental toxicity studies. Although there is quantitative evidence of increased susceptibility in the 2– generation reproduction study in rats, the degree of concern is low, because there is a well established offspring toxicity NOAEL in the study and the risk assessment team did not identify any residual uncertainties after establishing toxicity endpoints and traditional UFs to be used in the risk assessment of dicamba for all routes and durations of exposure, except acute oral exposures. iv. EPA selected an endpoint from the acute neurotoxicity study in rats for use in assessing acute oral exposures. In this study, neurotoxicity was seen in both sexes at the lowest dose tested, 300 mg/ kg/day. Since a NOAEL was not established in the study, EPA has determined that an FQPA safety factor of 3X should be used in acute oral risk assessments for dicamba to account for uncertainty arising from the use of the LOAEL instead of a NOAEL. EPA has reduced the factor from 10X to 3X based on the following considerations. A comparison of the acute neurotoxicity (ACN) study with the rat developmental toxicity study that showed similar clinical signs and a NOAEL of 160 mg/ kg/day after 10 days of treatment indicates that the NOAEL for the acute VerDate Aug<31>2005 18:23 Apr 01, 2008 Jkt 214001 neurotoxicity study is unlikely to be more than 3– fold lower than the LOAEL (ACN LOAEL/3 = 100 mg/kg; rat developmental study NOAEL = 160 mg/ kg). Therefore, it was determined that an uncertainty factor of 3X for extrapolation of LOAEL to NOAEL was adequate. v. There are no residual uncertainties identified in the exposure databases. The dietary food exposure assessments were performed based on 100%CT and tolerance-level residues. Conservative ground water and surface water modeling estimates were used. Similarly, conservative assumptions were used to assess post-application exposure of children as well as incidental oral exposure of toddlers. These assessments will not underestimate the exposure and risks posed by dicamba. E. Aggregate Risks and Determination of Safety Safety is assessed for acute and chronic risks by comparing aggregate exposure to the pesticide to the aPAD and cPAD. The aPAD and cPAD are calculated by dividing the LOC by all applicable UFs. For linear cancer risks, EPA calculates the probability of additional cancer cases given aggregate exposure. Short-term, intermediateterm, and long-term risks are evaluated by comparing aggregate exposure to the LOC to ensure that the MOE called for by the product of all applicable UFs is not exceeded. 1. Acute risk. Using the exposure assumptions discussed in this unit for acute exposure, the acute dietary exposure from food and water to dicamba will occupy 11% of the aPAD for infants less than 1 year old, the population with the greatest estimated exposure. Dicamba is currently registered for uses that could result in acute residential exposure of toddlers from episodic granule ingestion; however, the Agency has determined that it is not appropriate to aggregate acute dietary (food and water) and acute residential exposures for dicamba, since it is unlikely that high end dietary exposure would occur in the same day as high end oral residential exposure. High end oral residential exposure is aggregated with background dietary exposure in evaluating short-term risk (see Unit III.E.3.). 2. Chronic risk. Using the exposure assumptions described in this unit for chronic exposure, EPA has concluded that exposure to dicamba from food and water will utilize 6.7% of the cPAD for children, 1 to 2 years old, the population group with the greatest estimated exposure. Based the use PO 00000 Frm 00037 Fmt 4700 Sfmt 4700 17917 pattern, chronic residential exposure to residues of dicamba is not expected. 3. Short-term risk. Short-term aggregate exposure takes into account residential exposure plus chronic exposure to food and water (considered to be a background exposure level). Dicamba is currently registered for uses that could result in short-term residential exposure and the Agency has determined that it is appropriate to aggregate chronic food and water and short-term exposures for dicamba. Using the exposure assumptions described in this unit for short-term exposures, EPA has concluded that food, water, and residential exposures aggregated result in aggregate MOEs of 1,600 for adults and 1,000 for children. The MOE for adults takes into consideration combined residential handler and postapplication exposures from doing yardwork on treated turf. The MOE for children includes combined postapplication dermal and incidental oral exposures of toddlers playing on treated turf. 4. Intermediate-term risk. Intermediate-term aggregate exposure takes into account residential exposure plus chronic exposure to food and water (considered to be a background exposure level). Dicamba is not registered for use on any sites that would result in intermediate-term residential exposure. Therefore, the aggregate risk is the sum of the risk from food and water, which do not exceed the Agency’s level of concern. 5. Aggregate cancer risk for U.S. population. Dicamba has been classified as ‘‘not likely’’ to be a human carcinogen and is, therefore, not expected to pose a cancer risk. 6. Determination of safety. Based on these risk assessments, EPA concludes that there is a reasonable certainty that no harm will result to the general population, or to infants and children from aggregate exposure to dicamba residues. IV. Other Considerations A. Analytical Enforcement Methodology Adequate enforcement methodology is available to enforce the tolerance expression. Methods I and II (Gas Chromotography with Electron Capture Detection) in the Pesticide Analytical Manual (PAM) Volume II, are adequate for the enforcement of tolerances for residues of dicamba and its metabolite 5-OH dicamba in/on plant commodities and milk. B. International Residue Limits There are no CODEX, Canadian or Mexican maximum residues limits E:\FR\FM\02APR1.SGM 02APR1 17918 Federal Register / Vol. 73, No. 64 / Wednesday, April 2, 2008 / Rules and Regulations (MRLs) for residues of dicamba on sweet corn. mstockstill on PROD1PC66 with RULES V. Conclusion Therefore, tolerances are established for combined residues of dicamba, 3,6dichloro-o-anisic acid, and its metabolite, 3,6-dichloro-5-hydroxy-oanisic acid, in or on corn, sweet, forage at 0.50 ppm; corn, sweet, kernel plus cob with husks removed at 0.04 pm; and corn, sweet, stover at 0.50 ppm. VI. Statutory and Executive Order Reviews This final rule establishes tolerances under section 408(d) of FFDCA in response to a petition submitted to the Agency. The Office of Management and Budget (OMB) has exempted these types of actions from review under Executive Order 12866, entitled Regulatory Planning and Review (58 FR 51735, October 4, 1993). Because this rule has been exempted from review under Executive Order 12866, this rule is not subject to Executive Order 13211, Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled Protection of Children from Environmental Health Risks and Safety Risks (62 FR 19885, April 23, 1997). This final rule does not contain any information collections subject to OMB approval under the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., nor does it require any special considerations under Executive Order 12898, entitled Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations (59 FR 7629, February 16, 1994). Since tolerances and exemptions that are established on the basis of a petition under section 408(d) of FFDCA, such as the tolerance in this final rule, do not require the issuance of a proposed rule, the requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et seq.) do not apply. This final rule directly regulates growers, food processors, food handlers, and food retailers, not States or tribes, nor does this action alter the relationships or distribution of power and responsibilities established by Congress in the preemption provisions of section 408(n)(4) of FFDCA. As such, the Agency has determined that this action will not have a substantial direct effect on States or tribal governments, on the relationship between the national government and the States or tribal governments, or on the distribution of power and responsibilities among the various levels of government or between VerDate Aug<31>2005 18:23 Apr 01, 2008 Jkt 214001 the Federal Government and Indian tribes. Thus, the Agency has determined that Executive Order 13132, entitled Federalism (64 FR 43255, August 10, 1999) and Executive Order 13175, entitled Consultation and Coordination with Indian Tribal Governments (65 FR 67249, November 6, 2000) do not apply to this rule. In addition, This rule does not impose any enforceable duty or contain any unfunded mandate as described under Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 104–4). This action does not involve any technical standards that would require Agency consideration of voluntary consensus standards pursuant to section 12(d) of the National Technology Transfer and Advancement Act of 1995 (NTTAA), Public Law 104–113, section 12(d) (15 U.S.C. 272 note). VII. Congressional Review Act The Congressional Review Act, 5 U.S.C. 801 et seq., generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of this final rule in the Federal Register. This final rule is not a ‘‘major rule’’ as defined by 5 U.S.C. 804(2). List of Subjects in 40 CFR Part 180 Environmental protection, Administrative practice and procedure, Agricultural commodities, Pesticides and pests, Reporting and recordkeeping requirements. Dated: March 24, 2008. Daniel C. Kenny, Acting Director, Registration Division, Office of Pesticide Programs. Therefore, 40 CFR chapter I is amended as follows: I PART 180—[AMENDED] 1. The authority citation for part 180 continues to read as follows: I Authority: 21 U.S.C. 321(q), 346a and 371. 2. Section 180.227 is amended by alphabetically adding the following commodities to the table in paragraph (a)(1) to read as follows: I 180.227 PO 00000 Dicamba; tolerances for residues. (a) General. (1) * * * Frm 00038 Fmt 4700 Sfmt 4700 Commodity Parts per million * * * * Corn, sweet, forage ........ Corn, sweet, kernel plus cob with husks removed ......................... Corn, sweet, stover ........ * * * * * * * * * 0.50 0.04 0.50 * * [FR Doc. E8–6674 Filed 4–1–08; 8:45 am] BILLING CODE 6560–50–S ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA–HQ–OPP–2007–0338; FRL–8356–7] Flonicamid; Pesticide Tolerance Environmental Protection Agency (EPA). ACTION: Final rule. AGENCY: SUMMARY: This regulation establishes tolerances for combined residues of flonicamid and its metabolites TFNA, TFNA-AM, and TFNG in or on Brassica, leafy greens, subgroup 5B; hop, dried cones; okra; radish, tops; turnip, greens; vegetable, root, except sugar beet, subgroup 1B; and vegetable, tuberous and corm, subgroup 1C. It also increases established tolerances for combined residues of flonicamid and its metabolites TFNA and TFNA-AM in or on cattle, fat; cattle, meat; egg; goat, fat; goat, meat; horse, fat; horse, meat; milk; poultry, fat; poultry, meat; poultry, meat byproducts; sheep, fat; and sheep, meat. Interregional Research Project Number 4 (IR–4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA). This regulation also removes existing tolerances for flonicamid and its metabolites on mustard greens and potatoes which are superseded by the new tolerances on ‘‘Brassica, leafy greens, subgroup 5B’’ and ‘‘vegetable, tuberous and corm, subgroup 1C,’’ respectively. DATES: This regulation is effective April 2, 2008. Objections and requests for hearings must be received on or before June 2, 2008, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION). ADDRESSES: EPA has established a docket for this action under docket identification (ID) number EPA–HQ– OPP–2007–0338. To access the electronic docket, go to https:// www.regulations.gov, select ‘‘Advanced Search,’’ then ‘‘Docket Search.’’ Insert E:\FR\FM\02APR1.SGM 02APR1

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[Federal Register Volume 73, Number 64 (Wednesday, April 2, 2008)]
[Rules and Regulations]
[Pages 17914-17918]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-6674]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2007-0325; FRL-8356-6]


Dicamba; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for combined residues 
of dicamba and its 5-hydroxy metabolite in or on corn, sweet, forage; 
corn, sweet, kernel plus cob with husks removed; and corn, sweet, 
stover. Interregional Research Project Number 4 (IR-4) requested these 
tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective April 2, 2008. Objections and 
requests for hearings must be received on or before June 2, 2008, and 
must be filed in accordance with the instructions provided in 40 CFR 
part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION ).

ADDRESSES: EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2007-0325. To access the 
electronic docket, go to https://www.regulations.gov, select ``Advanced 
Search,'' then ``Docket Search.'' Insert the docket ID number where 
indicated and select the ``Submit'' button. Follow the instructions on 
the regulations.gov website to view the docket index or access 
available documents. All documents in the docket are listed in the 
docket index available in regulations.gov. Although listed in the 
index, some information is not publicly available, e.g., Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the Internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available in the electronic docket at https://www.regulations.gov, or, 
if only available in hard copy, at the OPP Regulatory Public Docket in 
Rm. S-4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., 
Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m., 
Monday through Friday, excluding legal holidays. The Docket Facility 
telephone number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Susan Stanton, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-5218; e-mail address: stanton.susan@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

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

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

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

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, any person may file an objection to 
any aspect of this regulation and may also request a hearing on those 
objections. You must file your objection or request a hearing on this 
regulation in accordance with the instructions provided in 40 CFR part 
178. To ensure proper receipt by EPA, you must identify docket ID 
number EPA-HQ-OPP-2007-0325 in the subject line on the first page of 
your submission. All requests must be in writing, and must be mailed or 
delivered to the Hearing Clerk as required by 40 CFR part 178 on or 
before June 2, 2008.
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please submit a copy of 
the filing that does not contain any CBI for inclusion in the public 
docket that is described in ADDRESSES. Information not marked 
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA 
without prior notice. Submit this copy, identified by docket ID number 
EPA-HQ-OPP-2007-0325, by one of the following methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail: Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery: OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only 
accepted during the Docket's normal hours of operation (8:30 a.m. to 4 
p.m., Monday through Friday, excluding legal holidays). Special 
arrangements should be made for deliveries of boxed information. The 
Docket Facility telephone number is (703) 305-5805.

II. Petition for Tolerance

    In the Federal Register of May 9, 2007 (72 FR 26375) (FRL-8128-1), 
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition ((PP) 0E6209) 
by Interregional Research Project Number 4 (IR-4), 500 College Road 
East, Suite 201 W, Princeton, NJ 08540-6635. The petition requested 
that 40 CFR 180.227 be amended by establishing tolerances for combined 
residues of the herbicide dicamba, 3,6-dichloro-o-anisic acid, and

[[Page 17915]]

its metabolite, 3,6-dichloro-5-hydroxy-o-anisic acid, in or on corn, 
sweet, forage at 0.50 parts per million (ppm); corn, sweet, kernel plus 
cob with husks removed at 0.04 ppm; and corn, sweet, stover at 0.50 
ppm. That notice referenced a summary of the petition prepared by BASF 
Corporation, the registrant, which is available to the public in the 
docket, https://www.regulations.gov. There were no comments received in 
response to the notice of filing.

III. Aggregate Risk Assessment and Determination of Safety

    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a 
reasonable certainty that no harm will result from aggregate exposure 
to the pesticide chemical residue, including all anticipated dietary 
exposures and all other exposures for which there is reliable 
information.'' This includes exposure through drinking water and in 
residential settings, but does not include occupational exposure. 
Section 408(b)(2)(C) of FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical 
residue....'' These provisions were added to FFDCA by the Food Quality 
Protection Act (FQPA) of 1996.
    Consistent with FFDCA section 408(b)(2)(D), and the factors 
specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available 
scientific data and other relevant information in support of this 
action. EPA has sufficient data to assess the hazards of and to make a 
determination on aggregate exposure for the petitioned-for tolerances 
for combined residues of dicamba on corn, sweet, forage at 0.50 ppm; 
corn, sweet, kernel plus cob with husks removed at 0.04 ppm; and corn, 
sweet, stover at 0.50 ppm. EPA's assessment of exposures and risks 
associated with establishing the tolerance follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children.
    Dicamba has low acute toxicity via the oral, dermal and inhalation 
routes. It is an eye and dermal irritant but it is not a skin 
sensitizer. Following oral administration, dicamba is rapidly absorbed 
and excreted in urine and feces. Consistent neurotoxic signs (e.g., 
ataxia, decreased motor activity, impaired righting reflex and gait) 
were observed in many studies in rats and rabbits at high doses. 
Prenatal developmental toxicity studies in rats and rabbits showed no 
evidence (qualitative or quantitative) of increased susceptibility 
following in utero or post-natal exposure to dicamba. There was an 
increased incidence of abortion in the rabbit developmental toxicity 
study at doses that also showed maternal toxicity. In a 2-generation 
reproduction study, offspring toxicity was manifested as decreased pup 
body weight gain in all generations at a dose lower than the parental 
systemic toxicity NOAEL. Dicamba is classified as ``Not Likely to be 
Carcinogenic to Humans'' by the oral route. Mutagenicity studies did 
not demonstrate evidence of mutagenic potential for dicamba although 
some positive results were reported in published literature.
    Specific information on the studies received and the nature of the 
adverse effects caused by dicamba as well as the no-observed-adverse-
effect-level (NOAEL) and the lowest-observed-adverse-effect-level 
(LOAEL) from the toxicity studies can be found at https://
www.regulations.gov in the document Dicamba: Human-Health Risk 
Assessment for Proposed Section 3 New Uses on Sweet Corn. The 
referenced document is available in the docket established by this 
action, which is described under ADDRESSES, and is identified as EPA-
HQ-OPP-2007-0325-0004 in that docket.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, the toxicological level of concern (LOC) is derived 
from the highest dose at which no adverse effects are observed (the 
NOAEL) in the toxicology study identified as appropriate for use in 
risk assessment. However, if a NOAEL cannot be determined, the lowest 
dose at which adverse effects of concern are identified (the LOAEL) is 
sometimes used for risk assessment. Uncertainty/safety factors (UFs) 
are used in conjunction with the LOC to take into account uncertainties 
inherent in the extrapolation from laboratory animal data to humans and 
in the variations in sensitivity among members of the human population 
as well as other unknowns. Safety is assessed for acute and chronic 
risks by comparing aggregate exposure to the pesticide to the acute 
population adjusted dose (aPAD) and chronic population adjusted dose 
(cPAD). The aPAD and cPAD are calculated by dividing the LOC by all 
applicable UFs. Short-term, intermediate-term, and long-term risks are 
evaluated by comparing aggregate exposure to the LOC to ensure that the 
margin of exposure (MOE) called for by the product of all applicable 
UFs is not exceeded.
    For non-threshold risks, the Agency assumes that any amount of 
exposure will lead to some degree of risk and estimates risk in terms 
of the probability of occurrence of additional adverse cases. 
Generally, cancer risks are considered non-threshold. For more 
information on the general principles EPA uses in risk characterization 
and a complete description of the risk assessment process, see https://
www.epa.gov/fedrgstr/EPA-PEST/1997/November/Day-26/p30948.htm. A 
summary of the toxicological endpoints for dicamba used for human risk 
assessment can be found at https://www.regulations.gov in the document 
Dicamba: Human-Health Risk Assessment for Proposed Section 3 New Uses 
on Sweet Corn. The referenced document is available in the docket 
established by this action, which is described under ADDRESSES, and is 
identified as EPA-HQ-OPP-2007-0325-0004 in that docket.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to dicamba, EPA considered exposure under the petitioned-for 
tolerances as well as all existing dicamba tolerances in 40 CFR 
180.227. EPA assessed dietary exposures from dicamba in food as 
follows:
    i. Acute exposure. Quantitative acute dietary exposure and risk 
assessments are performed for a food-use pesticide, if a toxicological 
study has indicated the possibility of an effect of concern occurring 
as a result of a 1-day or single exposure. In estimating acute dietary 
exposure to dicamba, EPA used food consumption information from the 
U.S. Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide 
Continuing Surveys of Food Intake by Individuals (CSFII). As to residue 
levels in food, EPA assumed all foods for which there are tolerances 
were treated and contain tolerance-level residues. No anticipated 
residues or percent crop

[[Page 17916]]

treated (PCT) data were used in the acute dietary exposure assessment.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA 1994-1996 
and 1998 CSFII. As to residue levels in food, EPA assumed all foods for 
which there are tolerances were treated and contain tolerance-level 
residues. No anticipated residues or percent crop treated (PCT) data 
were used in the chronic dietary exposure assessment.
    iii. Cancer. Based on the results of carcinogenicity studies in 
rats and mice, EPA has concluded that dicamba is ``not likely to be 
carcinogenic to humans.'' Consequently, a quantitative cancer exposure 
and risk assessment is not appropriate for dicamba.
    2. Dietary exposure from drinking water. The residues of concern in 
drinking water include dicamba and its major degradate, DCSA. The 
Agency lacks sufficient monitoring data to complete a comprehensive 
dietary exposure analysis and risk assessment for dicamba and DCSA in 
drinking water. Because the Agency does not have comprehensive 
monitoring data, drinking water concentration estimates are made by 
reliance on simulation or modeling taking into account data on the 
environmental fate characteristics of dicamba and DCSA. Further 
information regarding EPA drinking water models used in pesticide 
exposure assessment can be found at https://www.epa.gov/oppefed1/models/
water/index.htm.
    Based on the Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCI-
GROW) models, the combined estimated environmental concentrations 
(EECs) of dicamba and DCSA for acute exposures are estimated to be 367 
parts per billion (ppb) for surface water and 0.016 ppb for ground 
water. The combined EECs for chronic exposures are estimated to be 13.8 
ppb for surface water and 0.016 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For acute dietary risk 
assessment, the water concentration value of 367 ppb was used to assess 
the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 13.8 ppb was used to 
assess the contribution to drinking water.
    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, and flea and tick control on pets).
    Dicamba is currently registered for use on residential sites, 
including home lawns and golf courses. EPA assessed residential 
exposure using the following assumptions: Residential handlers are 
likely to be exposed to dicamba residues via dermal and inhalation 
routes during handling, mixing, loading and applying activities. Based 
on the current use patterns, EPA expects duration of handler exposure 
to be short-term (1-30 days). EPA assessed several residential handler 
scenarios and found that handlers who mix/load and apply dicamba using 
a hose-end sprayer have the highest estimated exposures.
    There is also potential for short-term (1-30 days) post-application 
exposure of adults and children/toddlers on lawns and other turf areas 
previously treated with dicamba, as well as the potential for acute, 
episodic exposure of toddlers from ingestion of granules containing 
dicamba. EPA assessed short-term dermal exposure of adults doing 
yardwork; short-term dermal and incidental oral exposure of toddlers 
playing on treated turf; and acute toddler exposure from episodic 
granule ingestion. Post-application inhalation exposures are expected 
to be negligible and were, therefore, not assessed.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    Unlike other pesticides for which EPA has followed a cumulative 
risk approach based on a common mechanism of toxicity, EPA has not made 
a common mechanism of toxicity finding as to dicamba and any other 
substances and dicamba does not appear to produce a toxic metabolite 
produced by other substances. For the purposes of this tolerance 
action, therefore, EPA has not assumed that dicamba has a common 
mechanism of toxicity with other substances. For information regarding 
EPA's efforts to determine which chemicals have a common mechanism of 
toxicity and to evaluate the cumulative effects of such chemicals, see 
EPA's website at https://www.epa.gov/pesticides/cumulative.

D. Safety Factor for Infants and Children

    1.In general. Section 408(b)(2)(C) of FFDCA provides that EPA shall 
apply an additional tenfold (``10X'') margin of safety for infants and 
children in the case of threshold effects to account for prenatal and 
postnatal toxicity and the completeness of the database on toxicity and 
exposure unless EPA determines based on reliable data that a different 
margin of safety will be safe for infants and children. This additional 
margin of safety is commonly referred to as the FQPA safety factor. In 
applying this provision, EPA either retains the default value of 10X 
when reliable data do not support the choice of a different factor, or, 
if reliable data are available, EPA uses a different additional FQPA 
safety factor value based on the use of traditional UFs and/or special 
FQPA safety factors, as appropriate.
    2. Prenatal and postnatal sensitivity. The prenatal and postnatal 
toxicology database for dicamba includes rat and rabbit developmental 
toxicity studies and a 2-generation reproduction toxicity study in 
rats. There was no evidence (qualitative or quantitative) of increased 
susceptibility following in utero exposure in the developmental 
toxicity studies in rats and rabbits. There was evidence of increased 
sensitivity of the offspring following pre-/postnatal exposure in the 
2-generation reproduction study in rats. In that study, offspring 
toxicity was manifested as decreased pup body weight in all generations 
at a dose lower than the parental systemic toxicity NOAEL. However, 
there is low concern and there are no residual uncertainties for the 
increased susceptibility for the following reasons. The NOAEL of 45 
milligrams/kilogram/day (mg/kg) identified in this study was chosen for 
risk assessments for all routes and exposure durations other than acute 
oral exposures. Since this NOAEL is the lowest (most sensitive 
endpoint) in the dicamba toxicity database, and the dose response 
observed in the study is well defined, assuring that this dose is a 
clear NOAEL, use of the NOAEL and endpoint for risk assessment is 
protective for all observed toxic effects of the chemical. The endpoint 
(decreased pup body weight) is not expected to occur as a result of a 
single (acute) exposure and was, therefore, not deemed appropriate for 
assessing acute oral exposures.
    3. Conclusion. EPA has determined that reliable data show that it 
would be safe for infants and children to reduce the FQPA safety factor 
to 3X for acute oral exposures and to 1X for all other routes and 
durations of exposure. That decision is based on the following 
findings:
    i. The toxicity database for Dicamba is complete.
    ii. A developmental neurotoxicity study is not required. Consistent

[[Page 17917]]

neurotoxic signs (e.g., ataxia, decreased motor activity, impaired 
righting reflex and gait) were observed in many studies in rats and 
rabbits at high doses. After considering the available toxicity data, 
however, EPA determined that there is no need for a developmental 
neurotoxicity study or additional UFs to account for neurotoxicity for 
the following reasons:
    a. Although clinical signs of neurotoxicity were seen in pregnant 
animals, no evidence of developmental anomalies of the fetal nervous 
system were observed in the prenatal developmental toxicity studies, in 
either rats or rabbits, at maternally toxic doses up to 300 or 400 mg/
kg/day, respectively;
    b. There was no evidence of behavioral or neurological effects on 
the offspring in the 2-generation reproduction study in rats; and
    c. The ventricular dilation of the brain in the combined chronic 
toxicity and carcinogenicity study in rats was only observed in females 
at the high dose after two years' exposure. The significance of this 
observation is questionable, since no similar histopathological finding 
was seen in the subchronic neurotoxicity study.
    iii. There is no evidence that dicamba results in increased 
susceptibility in in utero rats or rabbits in the prenatal 
developmental toxicity studies. Although there is quantitative evidence 
of increased susceptibility in the 2-generation reproduction study in 
rats, the degree of concern is low, because there is a well established 
offspring toxicity NOAEL in the study and the risk assessment team did 
not identify any residual uncertainties after establishing toxicity 
endpoints and traditional UFs to be used in the risk assessment of 
dicamba for all routes and durations of exposure, except acute oral 
exposures.
    iv. EPA selected an endpoint from the acute neurotoxicity study in 
rats for use in assessing acute oral exposures. In this study, 
neurotoxicity was seen in both sexes at the lowest dose tested, 300 mg/
kg/day. Since a NOAEL was not established in the study, EPA has 
determined that an FQPA safety factor of 3X should be used in acute 
oral risk assessments for dicamba to account for uncertainty arising 
from the use of the LOAEL instead of a NOAEL. EPA has reduced the 
factor from 10X to 3X based on the following considerations. A 
comparison of the acute neurotoxicity (ACN) study with the rat 
developmental toxicity study that showed similar clinical signs and a 
NOAEL of 160 mg/kg/day after 10 days of treatment indicates that the 
NOAEL for the acute neurotoxicity study is unlikely to be more than 3- 
fold lower than the LOAEL (ACN LOAEL/3 = 100 mg/kg; rat developmental 
study NOAEL = 160 mg/kg). Therefore, it was determined that an 
uncertainty factor of 3X for extrapolation of LOAEL to NOAEL was 
adequate.
    v. There are no residual uncertainties identified in the exposure 
databases. The dietary food exposure assessments were performed based 
on 100%CT and tolerance-level residues. Conservative ground water and 
surface water modeling estimates were used. Similarly, conservative 
assumptions were used to assess post-application exposure of children 
as well as incidental oral exposure of toddlers. These assessments will 
not underestimate the exposure and risks posed by dicamba.

E. Aggregate Risks and Determination of Safety

    Safety is assessed for acute and chronic risks by comparing 
aggregate exposure to the pesticide to the aPAD and cPAD. The aPAD and 
cPAD are calculated by dividing the LOC by all applicable UFs. For 
linear cancer risks, EPA calculates the probability of additional 
cancer cases given aggregate exposure. Short-term, intermediate-term, 
and long-term risks are evaluated by comparing aggregate exposure to 
the LOC to ensure that the MOE called for by the product of all 
applicable UFs is not exceeded.
    1. Acute risk. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from food and water 
to dicamba will occupy 11% of the aPAD for infants less than 1 year 
old, the population with the greatest estimated exposure. Dicamba is 
currently registered for uses that could result in acute residential 
exposure of toddlers from episodic granule ingestion; however, the 
Agency has determined that it is not appropriate to aggregate acute 
dietary (food and water) and acute residential exposures for dicamba, 
since it is unlikely that high end dietary exposure would occur in the 
same day as high end oral residential exposure. High end oral 
residential exposure is aggregated with background dietary exposure in 
evaluating short-term risk (see Unit III.E.3.).
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to dicamba 
from food and water will utilize 6.7% of the cPAD for children, 1 to 2 
years old, the population group with the greatest estimated exposure. 
Based the use pattern, chronic residential exposure to residues of 
dicamba is not expected.
    3. Short-term risk. Short-term aggregate exposure takes into 
account residential exposure plus chronic exposure to food and water 
(considered to be a background exposure level). Dicamba is currently 
registered for uses that could result in short-term residential 
exposure and the Agency has determined that it is appropriate to 
aggregate chronic food and water and short-term exposures for dicamba.
    Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded that food, water, and residential 
exposures aggregated result in aggregate MOEs of 1,600 for adults and 
1,000 for children. The MOE for adults takes into consideration 
combined residential handler and postapplication exposures from doing 
yardwork on treated turf. The MOE for children includes combined 
postapplication dermal and incidental oral exposures of toddlers 
playing on treated turf.
    4. Intermediate-term risk. Intermediate-term aggregate exposure 
takes into account residential exposure plus chronic exposure to food 
and water (considered to be a background exposure level). Dicamba is 
not registered for use on any sites that would result in intermediate-
term residential exposure. Therefore, the aggregate risk is the sum of 
the risk from food and water, which do not exceed the Agency's level of 
concern.
    5. Aggregate cancer risk for U.S. population. Dicamba has been 
classified as ``not likely'' to be a human carcinogen and is, 
therefore, not expected to pose a cancer risk.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, or to infants and children from aggregate 
exposure to dicamba residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology is available to enforce the 
tolerance expression. Methods I and II (Gas Chromotography with 
Electron Capture Detection) in the Pesticide Analytical Manual (PAM) 
Volume II, are adequate for the enforcement of tolerances for residues 
of dicamba and its metabolite 5-OH dicamba in/on plant commodities and 
milk.

B. International Residue Limits

    There are no CODEX, Canadian or Mexican maximum residues limits

[[Page 17918]]

(MRLs) for residues of dicamba on sweet corn.

V. Conclusion

    Therefore, tolerances are established for combined residues of 
dicamba, 3,6-dichloro-o-anisic acid, and its metabolite, 3,6-dichloro-
5-hydroxy-o-anisic acid, in or on corn, sweet, forage at 0.50 ppm; 
corn, sweet, kernel plus cob with husks removed at 0.04 pm; and corn, 
sweet, stover at 0.50 ppm.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this rule has been 
exempted from review under Executive Order 12866, this rule is not 
subject to Executive Order 13211, Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, 
May 22, 2001) or Executive Order 13045, entitled Protection of Children 
from Environmental Health Risks and Safety Risks (62 FR 19885, April 
23, 1997). This final rule does not contain any information collections 
subject to OMB approval under the Paperwork Reduction Act (PRA), 44 
U.S.C. 3501 et seq., nor does it require any special considerations 
under Executive Order 12898, entitled Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994).
    Since tolerances and exemptions that are established on the basis 
of a petition under section 408(d) of FFDCA, such as the tolerance in 
this final rule, do not require the issuance of a proposed rule, the 
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et 
seq.) do not apply.
    This final rule directly regulates growers, food processors, food 
handlers, and food retailers, not States or tribes, nor does this 
action alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. As such, the Agency has determined that 
this action will not have a substantial direct effect on States or 
tribal governments, on the relationship between the national government 
and the States or tribal governments, or on the distribution of power 
and responsibilities among the various levels of government or between 
the Federal Government and Indian tribes. Thus, the Agency has 
determined that Executive Order 13132, entitled Federalism (64 FR 
43255, August 10, 1999) and Executive Order 13175, entitled 
Consultation and Coordination with Indian Tribal Governments (65 FR 
67249, November 6, 2000) do not apply to this rule. In addition, This 
rule does not impose any enforceable duty or contain any unfunded 
mandate as described under Title II of the Unfunded Mandates Reform Act 
of 1995 (UMRA) (Public Law 104-4).
    This action does not involve any technical standards that would 
require Agency consideration of voluntary consensus standards pursuant 
to section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272 
note).

VII. Congressional Review Act

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

List of Subjects in 40 CFR Part 180

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

    Dated: March 24, 2008.
Daniel C. Kenny,
Acting Director, Registration Division, Office of Pesticide Programs.

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Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

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

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

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2. Section 180.227 is amended by alphabetically adding the following 
commodities to the table in paragraph (a)(1) to read as follows:


180.227  Dicamba; tolerances for residues.

    (a) General.
    (1) * * *

------------------------------------------------------------------------
                      Commodity                        Parts per million
------------------------------------------------------------------------
                                * * * * *
Corn, sweet, forage..................................               0.50
Corn, sweet, kernel plus cob with husks removed......               0.04
Corn, sweet, stover..................................               0.50
                                * * * * *
------------------------------------------------------------------------

* * * * *
[FR Doc. E8-6674 Filed 4-1-08; 8:45 am]
BILLING CODE 6560-50-S
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