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SUMMARY: This notice announces the filing of a pesticide petition proposing regulations establishing tolerances for residues of the insecticidal fluorine compounds cryolite and/or synthetic cryolite (sodium aluminum fluoride or sodium aluminofluoride) in or on potatoes and in processed potato waste. This notice includes a summary of the petition that was prepared by the petitioner, The Cryolite Task Force.
DATES: Comments, identified by the docket control number [PF-712] must be received on or before April 11, 1997.
ADDRESSES: By mail, submit written comments to: Public Response and Program Resources Branch, Field Operations Division (7506C), Office of Pesticide Programs, Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. In person, bring comments to: Rm. 1132 CM #2, 1921 Jefferson Davis Highway, Arlington, VA 22202.
Comments and data may also be submitted electronically by sending electronic mail (e-mail) to: opp-docket@epamail.epa.gov. Electronic comments must be submitted either in ASCII format (avoiding the use of special characters and any form of encryption) or in WordPerfect in 5.1 file format. All comments and data in electronic form must be identified by the docket control number [PF-712]. Electronic comments on this notice may be filed online at many Federal Depository Libraries. The official record for this rulemaking, as well as the public version described above, will be kept in paper form. Additional information on electronic submissions can be found in Unit II. of this document.
Information submitted as a comment concerning this notice may be claimed confidential by marking any part or all of that information as ``Confidential Business Information'' (CBI). Information so marked will not be
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disclosed except in accordance with procedures set forth in 40 CFR part 2. No CBI should be submitted through e-mail. A copy of the comment that does not contain CBI must be submitted for inclusion in the public record. Information not marked confidential may be disclosed publicly by EPA without prior notice.
FOR FURTHER INFORMATION CONTACT: William Jacobs, Acting, Product Manager 14, Registration Division, Office of Pesticide Programs, Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. Office location, telephone number, and e-mail address: Rm. 219, CM #2, 1921 Jefferson Davis Highway, Arlington, VA 22202. (703) 305-6600; e- mail: jacobs.william@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: EPA has received a pesticide petition from The Cryolite Task Force c/o Gowan, P.O. Box 5568, Yuma, AZ 85366. The petition proposes, pursuant to section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, to amend 40 CFR 180.145 to renew the regulations that established tolerances for the insecticidal fluorine compounds cryolite and/or synthetic cryolite in or on potatoes at 2.0 parts per million (ppm) and processed potato waste at 22 ppm.
EPA has determined that the petition contains data or information regarding the elements set forth in section 408(d)(2); however, EPA has not fully evaluated the sufficiency of the submitted data at this time or whether the data supports granting of the petition. Additional data may be needed before EPA rules on the petition.
As required by section 408(d) of the FFDCA, as recently amended by the Food Quality Protection Act (FQPA) (Pub. L. 104-170), The Cryolite Task Force included in the petition a summary of the petition and authorization for the summary to be published in the Federal Register in a notice of receipt of the petition. The summary represents the views of The Cryolite Task Force; EPA is in the process of evaluating the petition. As required by section 408(d)(3), EPA is including the summary as a part of this notice of filing. EPA may have made minor edits to the summary for purposes of clarity.
This submission amends petitions PP 9F3739 and FAP 1H5604 by providing the additional information specified by the FQPA. A permanent tolerance is proposed for residues of the insecticide sodium aluminofluoride (cryolite and/or synthetic cryolite) in or on the raw agricultural commodities (RAC) potatoes, as provided by the new FFDCA section 408. In addition, the petitioner proposes that EPA establish a permanent tolerance for residues of cryolite in processed potato waste, as provided under the new FFDCA section 408.
Time-limited tolerances for residues of sodium aluminofluoride (cryolite and/or synthetic cryolite) in/on potatoes and processed potato waste were initially granted on May 5, 1993. These tolerances expired on May 6, 1996. A time limitation was required initially for these regulations because a chronic dog feeding study and a two- generation rat reproduction study were outstanding. These two studies were submitted and were found acceptable in reviews dated April 13, 1994 (chronic dog) and February 24, 1995 (rat reproduction). In the Federal Register of May 8, 1996 (61 FR 20781) (FRL-5362-6), EPA proposed establishing permanent tolerances of 2 ppm and 22 ppm for residues of cryolite in/on potatoes and processed potato waste, respectively. A 30-day comment period was specified by the Agency for these proposed regulations. However, prior to publication of final regulations, the FQPA specified additional requirements for tolerance petitions. This submission amends PP 9F3739 and FAP 1H5604 by providing the additional information specified.
A. Residue Data
A Reregistration Eligibility Decision (RED) was issued for cryolite in August 1996. As documented in the May 8, 1996 Federal Register and reiterated in the RED, the Agency has determined that plant residues are inorganic surface residues of cryolite, measured as total fluoride; and that the residue of concern in animals also is total fluoride.
Provisions in the FQPA which are relevant to degradates or metabolites of pesticide chemical residues are not applicable to elemental fluorine.
Data previously reviewed by EPA show background levels of fluoride in untreated potatoes ranging from 0.14 ppm to 0.31 ppm. Levels of fluoride found in treated potatoes ranged from 0.18 ppm to 0.94 ppm.
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of cryolite which are measured as fluoride.
B. Toxicological Data
The cryolite RED concluded that the toxicological data base was adequate for a reregistration eligibility decision for numerous crop uses, including potatoes. No additional toxicology requirements were specified in the RED. The cryolite residue of toxicological concern is fluoride; and health effects identified for fluoride in humans and animals are skeletal and dental fluorosis. Dental fluorosis (mottling of tooth enamel) is not considered to be an adverse effect.
Further, the Agency has determined that although fluoride accumulation is demonstrated in a number of studies, the accumulation itself is not considered an adverse effect.
In a 90-day rat feeding study (MRID 00158000), cryolite was tested at dose levels of 0, 50, 5,000, and 50,000 ppm (corresponding to 0, 3.8, 399.2, and 4,172.3 mg/kg/day in males and 0, 4.5, 455.9, and 4,758.1 mg/kg/day in females). The NOEL was 50 ppm (3.8 mg/kg/day) for effects other than fluoride accumulation. The LOEL was 5,000 ppm (399.2 mg/kg/day) based on lesions observed in the stomach. Fluoride accumulated at all dose levels in this study. Cryolite was tested in a 90-day dog feeding study (MRID 00157999) at dose levels of 0, 500, 10,000, and 50,000 ppm (corresponding to 0, 17,368, and 1,692 mg/kg/ day). The NOEL was 10,000 ppm (368 mg/kg/day). The LOEL was 50,000 ppm (1,692 mg/kg/day) for effects other than fluoride accumulation. Fluoride accumulation occurred at all dose levels.
A 21-day subchronic dermal toxicity study in rabbits (MRID 41224801) is considered invalid because it is likely that cryolite was ingested by the test animals during the study. For this reason, the systemic dermal NOEL and LOEL could not be determined from this study. EPA noted in the RED that an additional subchronic dermal study is not necessary, because based on its chemical/physical properties, cryolite would not be absorbed through the skin to any appreciable extent.
The following specific chronic/oncogenicity studies are included in the cryolite toxicology data base:
A 2-year bioassay in B6C3F1 mice (HED DOC No. 009682) was conducted by the National Toxicology Program (NTP) using sodium fluoride as the test material at dose levels of 0, 25, 100, and 175 ppm, in water, representing 0, 2.4, 9.6, and 16.7 mg/kg/day in males and 0, 2.8, 11.3, and 18.8 mg/kg/day in females. The NOEL was less than 25 ppm (2.4 mg/ kg/day). The LOEL was 25 ppm (2.4 mg/kg/day) based on attrition of the teeth in males, discoloration and mottling of the teeth in males and females, and increased bone fluoride in both sexes. NTP considered that there was no evidence of carcinogenic activity in male and female mice.
A 2-year bioassay in F344/N rats (HED DOC No. 009682) also was conducted by the NTP using sodium fluoride as the test material at dose levels of 0, 25, 47, 100, and 175 ppm, in water, representing 0, 1.3, 5.2, and 8.6 mg/kg/day in males and 0, 1.3, 5.5, and 9.5 mg/kg/day in females. Osteosarcoma of the bone was observed only in 1 male of 50 (1/ 50) in the 100 ppm group and in 3 of 80 (3/80) males in the 175 ppm group. The NOEL was less than 25 ppm (1.3 mg/kg/day). The LOEL was 25 ppm (1.3 mg/kg/day) based on mottling of teeth, dentine incisor dysplasia, increased serum, urine and bone fluoride levels in males and females and incisor odontoblast and incisor ameloblast degeneration in males. NTP considered that there was ``equivocal evidence'' of carcinogenic activity in male rats in this study and ``no evidence'' of carcinogenic activity in female rats.
EPA concluded in the May 8, 1996 Federal Register and reiterated in the cryolite RED that the NTP studies utilizing sodium fluoride in lieu of cryolite satisfy the guideline study requirements for both the rodent chronic feeding study and the rat carcinogenicity study. Fluoride has been identified as the residue of toxicological concern in cryolite and synthetic cryolite and these compounds act as free fluoride. It should be noted that the NTP studies, which utilized freely soluble NaF represent a worst-case toxicological scenario on a ppm basis compared to what would be expected with cryolite per se, from which fluoride ion dissociation is much more limited.
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A 1-year chronic dog feeding study (MRID 42575101) was conducted with cryolite at dose levels of 0, 3,000, 10,000, and 30,000 ppm, representing 0, 95, 366, and 1,137 mg/kg/day in males and 0, 105, 387, and 1,139 mg/kg/day in females (in terms of fluoride, the doses are 0, 51, 198, and 614 mg F/kg/day for males and 0, 57, 209, and 615 mg F/kg/ day for females). The NOEL was less than 3,000 ppm (95 mg/kg/day in males and 105 mg/kg/day in females). The LOEL was 3,000 ppm based on increases in emesis, nucleated cells in males, renal lesions, and a decrease in urine-specific gravity in females.
The National Research Council (NRC) has reviewed the potential for reproductive effects from fluoride per se. In the report Health Effects of Ingested Fluoride, the NRC concluded that:
There have been reports of adverse effects on reproductive outcomes associated with high levels of fluoride in many animal species. In most of the studies, however, the fluoride concentrations associated with adverse effects were far higher than those encountered in drinking water. The apparent threshold concentration for inducing reproductive effects was 100 mg/L in mice, rats, foxes and cattle; 100-200 mg/L in minks, owls and kestrels; and over 500 mg/L in hens. Based on these findings, the subcommittee concludes that the fluoride concentrations associated with adverse reproductive effects in animals are far higher than those to which human populations are exposed. Consequently, ingestion of fluoride at current concentrations should have no adverse effects on human reproduction.
In addition, it should be noted that national and international regulatory organizations (U.S. EPA Office of Water, U.S. DHHS, the Canadian Government, and the World Health Organization) have assessed potential health risks from exposure to fluoride. EPA has concluded that the endpoints and estimated effect levels documented by these organizations are similar and that the health effects of fluoride in animals and humans include dental and skeletal fluorosis. Endocrine effects have not been recognized as toxicological endpoints for fluoride by any worldwide regulatory authority.
C. Aggregate Exposure
However, fluoride is intentionally supplemented to drinking water for prevention of dental caries and may also be present at natural background levels. The U.S. Public Health Service recommends an optimal fluoride concentration of 0.7 to 1.2 mg/L to prevent dental caries and minimize dental fluorosis.
Fluoride levels in public drinking water are regulated under the Safe Drinking Water Act. A Maximum Concentration Limit (MCL) of 4.0 mg/ L (0.114 mg/kg/day) has been established. EPA has previously estimated that levels of fluoride in/on food from the agricultural use of cryolite plus fluoride levels in U.S. drinking water supplies results in a daily dietary intake of fluoride of approximately 0.095 mg/kg/day. This is substantially less than the Maximum Concentration Limit (MCL) of 4.0 mg/L (0.144 mg/kg/day), a level which provides no known or anticipated adverse health effect as determined by the Surgeon General.
As noted in the May 8, 1996 Federal Register and reiterated in the RED, the Agency has concurred with the findings
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of the Surgeon General that adverse health effects have not been found in the U. S. population below 8 mg F/L (0.23 mg/kg/day).
The residue of toxicological concern in cryolite is fluoride. Although fluoride supplements in drinking water are not considered to be pesticidal substances, the dietary contribution of drinking water to overall fluoride exposure has been discussed elsewhere in this summary. Current tolerances for insecticidal fluorine-containing compounds are limited to cryolite and synthetic cryolite. For this reason, consideration of potential cumulative effects of residues from pesticidal substances other than sodium aluminofluoride with a common mechanism of toxicity are not applicable.
E. Safety Determination
These data show clearly that no additional margin of safety is required for exposure of infants and children to cryolite. The developmental NOEL ranges from more than 166x (rabbit) to more than 16,000x (rat) for the maximum combined exposure of infants and children to residues of fluoride from all agricultural uses of cryolite plus drinking water. The reproductive NOEL is about 256x greater than maximum combined exposure of infants and children to residues of fluoride.
F. International Tolerances
No Codex, EC or other international tolerances are in effect for cryolite; thus, potential dietary exposure to fluoride from the agricultural use of cryolite on crops would not include imported foodstuffs.
Electronic comments can be sent directly to EPA at: opp-docket@epamail.epa.gov
Electronic comments must be submitted as an ASCII file avoiding the use of special characters and any form of encryption.
The official record for this rulemaking, as well as the public version, as described above will be kept in paper form. Accordingly, EPA will transfer all comments received electronically into printed, paper form as they are received and will place the paper copies in the official rulemaking record which will also include all comments submitted directly in writing. The official rulemaking record is the paper record maintained at the address in ``ADDRESSES'' at the beginning of this document.
List of Subjects
Environmental protection, Administrative practice and procedure, Agricultural commodities, Pesticides and pests, Reporting and recordkeeping requirements.
Dated: February 24, 1997. Peter Caulkins, Acting Director, Registration Division, Office of Pesticide Programs. [FR Doc. 97-6015 Filed 3-11-97; 8:45 am] BILLING CODE 6560-50-F