UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D. C. 20460 OFFICE OF PREVENTION, PESTICIDES AND TOXIC SUBSTANCES TXR No. 0052456 MEMORANDUM DATE: 04/ 01/ 2004 SUBJECT: 106201. Toxicology Disciplinary Chapter for the Reregistration Eligibility Decision Document ( Tolerance Reassessment ( TRED))

PC Code: 106201 DP Barcode: D300298 TO: John W. Pates, Jr. Chemical Review Manager # 51 Reregistration Branch 1 Special Review and Reregistration Division ( 7508C)

FROM: Pamela M. Hurley, Toxicologist Reregistration Branch 3 Health Effects Division ( 7509C)

THRU: Catherine Eiden, Chief Reregistration Branch 3 Health Effects Division ( 7509C)

Background and Summary:

The Health Effects Division was asked to review and/ or update all the major toxicology studies conducted with Amitraz for a tolerance reassessment ( TRED) and prepare the toxicology chapter. The toxicology chapter is attached to this memorandum. 2 AMITRAZ PC Code: 106201 Toxicology Disciplinary Chapter for the Reregistration Eligibility Decision Document Date completed: April 1, 2004 Prepared by: Pamela M. Hurley form: FINAL June 21, 2000 3 TABLE OF CONTENTS 1.0 HAZARD CHARACTERIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.0 REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.0 DATA GAP( S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.0 HAZARD ASSESSMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1 Acute Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 Subchronic Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.3 Prenatal Developmental Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.4 Reproductive Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.5 Chronic Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.6 Carcinogenicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.7 Mutagenicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.8 Neurotoxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.9 Metabolism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 5.0 TOXICITY ENDPOINT SELECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.1 See Section 9.2 for Endpoint Selection Table. . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.2 Dermal Absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.3 Classification of Carcinogenic Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 6.0 FQPA CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 6.1 Special Sensitivity to Infants and Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 6.2 Recommendation for a Developmental Neurotoxicity Study . . . . . . . . . . . . . . . . 26 7.0 OTHER ISSUES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 8.0 REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 9.0 APPENDICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 9.1 Toxicity Profile Summary Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 9.1.1 Acute Toxicity Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 9.1.2 Subchronic, Chronic and Other Toxicity Tables . . . . . . . . . . . . . . . . . . . 31 9.2 Summary of Toxicological Dose and Endpoints for Amitraz for Use in Human Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 4 1.0 HAZARD CHARACTERIZATION The toxicological database for Amitraz is inadequate for assessment of risk to infants and children. Significant data gaps exist, which include an acceptable developmental rabbit study and multi generation reproduction study. There is also concern for neurotoxicity and developmental neurotoxicity. No studies are available which access potential neurotoxicity. Therefore, in order to fulfill the requirements for a new multi generation reproduction study, developmental neurotoxicity study and a mammalian neurotoxicity screening battery, a 2 generation reproduction study with additional components is required. To address the instability of the test material in the diet, this study is to be conducted by gavage, including the pups. The study will include an assessment for potential developmental neurotoxicity and for potential adult neurotoxicity. The adult neurotoxicity section will include assessment protocols from the mammalian subchronic neurotoxicity protocol. In addition to the studies required for FQPA, a requirement for a 28 day inhalation study has been placed on reserve pending future uses for amitraz.

Amitraz has a low acute toxicity in a wide number of species. It has been tested in mice, rats, guinea pigs, rabbits, dogs, baboons and domestic pigs by the oral, dermal and inhalation routes of exposure. In the Registration Standard ( TXR 005633), a pharmacotoxic profile suggests a depression of hypothalmic function. Clinical signs of toxicity include central nervous system depression, ataxia, ptosis, emesis, labored respiration, muscular weakness, tremors, hypothermia and bradycardia. These signs varied in severity depending upon the species. The dog appears to be the most sensitive species, with the baboon approximately 2.5 times less sensitive, followed by the rat and guinea pig ( 5 times less sensitive). The mouse appears to be the least sensitive ( 15 times less sensitive). Metabolism studies in humans indicate clinical signs similar to those observed in animals. These signs were reported within 90 to 160 minutes after ingestion and included sedation, dry mouth, disorientation, bradycardia, hypertension and hypothermia persisting up to 12 hours after dosing.

Metabolism studies have been conducted in the mouse, rat, cat, dog, baboon and man. The major metabolites of amitraz include N( 2,4 dimethylphenyl) N methylformamidine; 2,4 dimethylformanilide; 2,4 dimethylaniline; 4 amino 3 methylbenzoic acid; 4 formamido 3 methyl benzoic acid; 4 acetamido 3 methyl benzoic acid; and N, N bis 2,4 dimethylphenylformamidine. 2,4 dimethylaniline is included in the tolerance expression along with the parent.

Clinical signs of neurotoxicity and decreased body weights appear to be the major targets for amitraz. A comparison of the subchronic and chronic studies indicates that there does not appear to be any issues of cumulative toxicity ( i. e. no increased toxicity with a longer term of exposure). The dog is the most sensitive species, although the clinical signs appear early in the chronic study and do not reappear. Similar clinical signs are observed when amitraz is administered via all three routes of exposure: oral, dermal and inhalation. There does not appear to be any extra sensitivity in any one sex. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 5 There is no indication of developmental toxicity in the rat in either of two available studies ( one unacceptable study and an acceptable repeat study). Two studies are available in the rabbit; however, niether are acceptable due to deficiencies in either the study designs and/ or the studies themselves. In the first rabbit study, at a dose level where decreased body weight gains and abortions were observed in the does, decreased litter size, decreased implantations, increased postimplantation loss, abortions and decreased mean fetal body weight had been observed. However, the study needed to be repeated because there were too few litters available for analysis, limited data available in the report and an unclear method of dosing. No developmental toxicity was observed in the second rabbit study; however this study is not acceptable due to too few available litters in the two treated groups and pre existing maternal respiratory infections. In addition, this study was not tested at as high a dose as in the first study. In the repeat study, an apparent increase in early resorptions and percent postimplantation loss was seen at the highest dose tested; however, these increases were due to the fact that three does at this dose totally resorbed their litters ( 88% of the early resorptions were found in the three does which displayed total litter resorptions). It might be possible that developmental toxicity could be observed at a higher dose if a new study were conducted. In summary, there is no evidence ( quantitative or qualitative) of increased susceptibility following pre natal exposure to rats. However, evidence for susceptibility following pre natal exposure to rabbits could not be ascertained due to deficiencies in either the study designs and/ or study reports.

Two reproduction studies are available, a 1 generation and a 3 generation study. In the 1 generation reproduction study, at the same LOAEL, the parents exhibit a mean decrease in body weight gain whereas the pups exhibit a lower mean litter size at birth and on lactation day 4. In the 3 generation reproduction study, the parents exhibit a mean decrease in body weight gain during the F0 premating period at the LOAEL. At the parental NOAEL, the pups exhibit decreased survival and mean litter size during lactation. Unfortunately, neither study is unacceptable for regulatory purposes. In the 1 generation study, the animals are not tested over at least two generations, only limited information were provided and the purity of the test compound was not available. In the 3 generation reproduction study, again, limited data were provided, mating was not 1 male to 1 female, no data on reproductive organs were provided, litter data only provided for a few time points, and histopathology data were not provided. In summary, evidence for susceptibility following pre and/ or postnatal exposure to rats could not be ascertained due to many deficiencies in study designs and/ or study reports.

In rats, there is no indication of potential carcinogenicity for amitraz; however, in female mice amitraz induces significant dose related positive trends in hepatocellular adenomas, carcinomas and in combined adenomas/ carcinomas. Females also had a significant increase in the pair wise comparison of controls and the highest dose group in hepatocellular adenomas, carcinomas and in combined adenomas and/ or carcinomas. Male mice had a significant dose related positive trend in lung adenomas. In addition, males had a significant increase in the pair wise comparison of controls and the highest dose group in lung adenomas. Amitraz is classified as a Group C, possible human carcinogen. The Q 1* has been calculated to be 2.83 x 10 2 in human equivalents AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 6 using the 3/ 4' s scaling factor, reflecting the 1994 Agency policy. Amitraz has not been shown to induce gene mutations in either bacterial or mammalian cells, is not clastogenic in an in vitro study, does not induce unscheduled DNA synthesis in mammalian cells, and does not induce cell transformations in C3H/ 10T1/ 2 cells derived from mouse embyro fibroblasts under the conditions in which the studies were conducted.

2.0 REQUIREMENTS The requirements ( CFR 158.340) for Food Uses for Amitraz are in Table 1. Use of the new guideline numbers does not imply that the new ( 1998) guideline protocols were used. Table 1.

Test Technical Required Satisfied 870.1100 Acute Oral Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . 870.1200 Acute Dermal Toxicity . . . . . . . . . . . . . . . . . . . . . . 870.1300 Acute Inhalation Toxicity . . . . . . . . . . . . . . . . . . . . 870.2400 Primary Eye Irritation . . . . . . . . . . . . . . . . . . . . . . . 870.2500 Primary Dermal Irritation . . . . . . . . . . . . . . . . . . . . 870.2600 Dermal Sensitization . . . . . . . . . . . . . . . . . . . . . . . . yes yes yes yes yes yes yes yes yes yes yes yes 870.3100 Oral Subchronic ( rodent) . . . . . . . . . . . . . . . . . . . . . 870.3150 Oral Subchronic ( nonrodent) . . . . . . . . . . . . . . . . . . 870.3200 21 Day Dermal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 870.3250 90 Day Dermal . . . . . . . . . . . . . . . . . . . . . . . . . . . . No # 28 Day Inhalation . . . . . . . . . . . . . . . . . . . . . . . . . . 870.3465 90 Day Inhalation . . . . . . . . . . . . . . . . . . . . . . . . . . yes yes yes no reserve4 no yes1 yes2 no3 n/ a no n/ a 870.3700a Developmental Toxicity ( rodent) . . . . . . . . . . . . . . . 870.3700b Developmental Toxicity ( nonrodent) . . . . . . . . . . . . 870.3800 Reproduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . yes yes yes yes no3 no3 870.4100a Chronic Toxicity ( rodent) . . . . . . . . . . . . . . . . . . . . 870.4100b Chronic Toxicity ( nonrodent) . . . . . . . . . . . . . . . . . 870.4200a Oncogenicity ( rat) . . . . . . . . . . . . . . . . . . . . . . . . . . 870.4200b Oncogenicity ( mouse) . . . . . . . . . . . . . . . . . . . . . . . 870.4300 Chronic/ Oncogenicity ( rat) . . . . . . . . . . . . . . . . . . . yes yes yes yes yes yes1 yes yes1 yes yes 870.5100 Mutagenicity C Gene Mutation  bacterial . . . . . . . . . 870.5300 Mutagenicity C Gene Mutation  mammalian . . . . . . 870.5375 Mutagenicity C Structural Chromosomal Aberrations 870.5550 Mutagenicity C Other Genotoxic Effects . . . . . . . . . . yes yes yes no yes yes yes yes 870.6100a Acute Delayed Neurotox. ( hen) . . . . . . . . . . . . . . . . 870.6100b 90 Day Neurotoxicity ( hen) . . . . . . . . . . . . . . . . . . . 870.6200a Acute Neurotox. Screening Battery ( rat) . . . . . . . . . 870.6200b 90 Day Neuro. Screening Battery ( rat) . . . . . . . . . . . 870.6300 Develop. Neuro . . . . . . . . . . . . . . . . . . . . . . . . . . . . no no no yes yes

no no no 870.7485 General Metabolism . . . . . . . . . . . . . . . . . . . . . . . . 870.7600 Dermal Penetration . . . . . . . . . . . . . . . . . . . . . . . . . yes no yes yes AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Test Technical Required Satisfied 7 Special Studies for Ocular Effects Acute Oral ( rat) . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subchronic Oral ( rat) . . . . . . . . . . . . . . . . . . . . . . . . Six month Oral ( dog) . . . . . . . . . . . . . . . . . . . . . . . no no no n/ a n/ a n/ a 1 Satisfied by an acceptable combined chronic/ oncogenicity study in the rat 2 Satisfied by an acceptable chronic study in the dog 3 Available 21 day dermal and developmental studies in the rabbit and reproduction study in the rat unacceptable 4 The requirement for a 28 day inhalation study has been placed on reserve pending future uses for amitraz 3.0 DATA GAP( S)

° Prenatal developmental toxicity study in rabbits ( 870.3700)

° A two generation reproduction study which should be MODIFIED to include the following:

° Due to the concern for the lack of stability of the test material in the diet, treatment should be via oral ( gavage) administration.

° The potential for neurotoxicity in the developing fetuses should be evaluated according to the OPPTS Guideline § 870.6300.

° The potential for neurotoxicity in adults should be evaluated according to the OPPTS Guideline § 870.6200.

The HIARC determined that the 10X UF DB should be applied to dietary ( acute and chronic) and non dietary ( incidental oral, dermal and inhalation) risk assessments because the required studies may provide endpoints applicable for risk assessments.

° Reserved pending future uses for amitraz: a 28 day inhalation study which should follow the OPPTS Guidance 870.3465, with cessation of exposure at 28 days. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 8 4.0 HAZARD ASSESSMENT 4.1 Acute Toxicity Adequacy of data base for acute toxicity: The data base for acute toxicity is considered complete. No additional studies are required at this time. Amitraz is not severely acutely toxic by the oral, dermal and inhalation routes. The Toxicity Category for the dermal route is low ( Category II) because it was not tested higher than 200 mg/ kg. Clinical signs of toxicity include central nervous system depression, ataxia, ptosis, emesis, labored respiration, muscular weakness, tremors, hypothermia and bradycardia.

The standard acute toxicity data on Amitraz Technical are summarized below in Table 2.

Table 2. Acute Toxicity Data on AMITRAZ Guideline No./ Study Type MRID No. Results Toxicity Category 870.1100 Acute oral toxicity 00041539 LD 50: 531 mg/ kg ( M) 515 mg/ kg ( F) III 870.1200 Acute dermal toxicity 00040862 LD 50: > 200 mg/ kg II 870.1300 Acute inhalation toxicity 00029963 LC 50: 2.4 mg/ L III 870.2400 Acute eye irritation 00040861 Non irritating IV 870.2500 Acute dermal irritation 00040862 Non irritating IV 870.2600 Skin sensitization 00029965 Not a sensitizer under conditions of study N/ A 4.2 Subchronic Toxicity Adequacy of data base for subchronic toxicity: The data base for subchronic toxicity is considered incomplete. A new 28 day inhalation study is required. Available subchronic studies include 90 day feeding studies in rats and dogs, a 21 dermal study in rabbits and a 21 day inhalation study in rats. None of the subchronic studies are considered to be acceptable; however the data requirement for subchronic oral studies in rodents and nonrodents is satisfied by the acceptable chronic studies in dogs and rats. The studies are not acceptable for one or more of the following reasons: lack of individual animal data, no information provided on the test material, AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 9 including concentration analyses, too few animals tested per dose group, concurrent infections and limited microscopic examinations.

870.3100 90 Day Oral Toxicity  Rat In a 90 day oral toxicity study ( MRID 00051784) Amitraz (% a. i. and batch/ lot # not provided) was administered to 21 Ash Wistar rats/ sex/ dose ( 42 controls/ sex) by gavage in a dose volume of 0.5 ml/ kg 0.4% Cellosize solution at dose levels of 0, 3, 12, 50 and 200 mg/ kg bw/ day. The 50 mg/ kg/ day group received 50 mg/ kg/ day for 7 days, followed by 11 weeks untreated and then 50 mg/ kg/ day for 7 days. The 200 mg/ kg/ day group only received 200 mg/ kg/ day for 7 days. The remaining groups were treated for 90 days. Body weights, hematological and clinical chemistry values and organ weights were measured and microscopic examinations were conducted.

Animals in the 200 mg/ kg group were euthanized after seven days of dosing due to their poor condition. They were observed to be irritable and shed red tears immediately after dosing and were also hunched, lethargic, weak, emaciated and squealed when handled. Treatment for the 50 mg/ kg group was discontinued after 7 days due to similar signs of toxicity . These animals recovered within 7 days. When dosing was re instituted on week 13 of the study, the signs recurred; one male and one female died. Occasional irritability and excitability were reported in the 12 mg/ kg/ group. There were no clinical signs of toxicity in the 3 mg/ kg/ group.

Body weight and body weight gain were confounded by the deaths of the animals in the 200 mg/ kg/ day group and the discontinuation of treatment in the 50 mg/ kg group. Overall body weight gain was significantly reduced in the 12 mg/ kg/ day group males. The absolute weight of the majority of the organs from the 50 mg/ kg group were decreased, most likely due to the decrease in body weight; however, there were changes in some of the relative organ weights, especially at 50 mg/ kg/ day. No data were provided for the 200 mg/ kg group. Microscopic examination indicated the following: at 50 mg/ kg/ day, swollen acinar cells or loss of acinar cells in the salivary gland were increased. After a 3 week recovery period, swollen acini in the salivary gland remained and congestion of the spleen and early involution of the thymus were increased. At 50 mg/ kg/ day and above, congestion of the spleen, heart and pituitary; early thymic involution and vacuolation of the liver. At 200 mg/ kg/ day, fatty infiltration of the adrenals and epithelial degeneration and eosinophilia in the epithelium of the trachea were observed. The LOAEL is 12 mg/ kg/ day, based on irritability and excitability and reduced overall body weight gain. The NOAEL is 3 mg/ kg/ day.

This 90 day oral toxicity study in the rat is unacceptable guideline does not satisfy the guideline requirement for a 90 day oral toxicity study ( OPPTS 870.3100; OECD 408) in the rat. It is not upgradable. No individual animal data were submitted for either the clinical signs or the gross necropsy examinations and no information was provided on the test material. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 10 870.3150 90 Day Oral Toxicity  Dog In a 90 day oral toxicity study ( MRID 00040345) Amitraz (% a. i. and batch/ lot # not provided) was administered to 2 beagle dogs/ sex/ dose in capsules at dose levels of 0, 0.25, 1.0, or 4.0 mg/ kg bw/ day for 90 days. Clinical signs were monitored; body weight and temperature, hematology, clinical chemistry, urinalysis and organ weight parameters were measured; and gross and microscopic examinations were conducted.

At 1.0 mg/ kg/ day and above, transient central nervous system depression, decrease in pulse rate, increase in glucose in the urine, neutrophilia of the bone marrow, hypothermia, increases in absolute and relative liver weights and an increase in the extent of liver lesions were noted. At 4.0 mg/ kg/ day, ataxia, emesis and catarrhal conjunctivitis were also observed. The LOAEL is 1.0 mg/ kg/ day, based on CNS depression, decrease in pulse rate, increase in glucose in the urine, hypothermia, neutrophilia of the bone marrow and increased liver weights and extent of liver lesions. The NOAEL is 0.25 mg/ kg/ day.

This 90 day oral toxicity study in the dog is unacceptable guideline and does not satisfy the guideline requirement for a 90 day oral toxicity study ( OPPTS 870.3150; OECD 409) in a nonrodent species. The study is unacceptable because only 2 dogs/ sex/ dose were tested. It is not upgradable.

870.3200 21/ 28 Day Dermal Toxicity B Rabbit In a 21 day dermal toxicity study ( MRID 00029972), BTS 27 419 ( Amitraz in acetone: % a. i. and batch/ lot # not provided) was applied to the shaved skin of 4 New Zealand White rabbits/ sex/ dose at dose levels of 0, 50 or 200 mg/ kg bw/ day, 6 hours/ day for 5 days/ week during a 21 day period.

At 200 mg/ kg, sedation was observed in both sexes, starting after the second or third dose. In males, a slight to moderate erythematous reaction that persisted throughout the study was observed only in males and was accompanied by desquamation of the skin and subcutaneous hemorrhage in one male. This male died on the last day of treatment. The 3 surviving males steadily lost weight throughout the study. Three out of 4 of both sexes had decreased food consumption, beginning in either the first or second week and continuing until either death or study termination. Three females died on days 15, 17 and 20. Decreased testicular weights were observed. This decrease corresponded with tubular degeneration observed in the microscopic examinations.

At 50 mg/ kg/ day, the males were sedated, starting after the 3rd or 4th dose. Slight to moderate erythematous reactions were observed in the treated area of the skin. One male had some desquamation and subcutaneous hemorrhage during the final week of treatment. One male stopped eating shortly after the treatment commenced and was found dead on day 6. One of the 3 AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 11 surviving males lost weight while the other two showed little change in weight, even with decreased food consumption in the second and third weeks of dosing.

There were indications of infection ( bacterial and/ or parasitic) in a few animals in all groups. It is not known how this may have affected the outcome of the study.

The LOAEL is 50 mg/ kg/ day, based on clinical signs and a decrease in food consumption in males. The NOAEL cannot be determined.

The dermal irritation LOAEL is 50 mg/ kg/ day based on slight to moderate erythematous reactions in the treated area of the skin in 3 out of 4 males accompanied by some desquamation and subcutaneous hemorrhage in 1 of the 3 males. The dermal irritation NOAEL cannot be determined.

This 21 day dermal toxicity study in the rabbit is unacceptable guideline and does not satisfy the guideline requirement for a 21 day dermal toxicity study ( OPPTS 870.3200 ; OECD 410) in the rabbit. It is not upgradable. Too few animals were tested per dose group, there were concurrent infections and a lack of information on the substance tested and limited histopathological investigations were conducted.

870.3465 21 Day Inhalation B Rat In a subchronic inhalation toxicity study ( MRID 00029964) [ Amitraz, (% a. i., batch/ lot # not provided)] was administered to 6 CFHB rats/ sex/ concentration by dynamic whole body exposure at nominal concentrations of 0, 0.01, 0.1 or 1.0 mg dust/ L for 6 hours per day for 14 days over a period of 3 weeks. Analytical concentrations were not measured.

No treatment related effects were observed at 0.01 mg/ L. A decrease in body weight gain was observed in females ( 66% of the control group). No statistical data or standard deviations were provided. An examination of the individual animal data do not indicate any significant outliers; however, the mean body weight was 94% of the control group and no other parameters indicated any effects at this concentration level.

At 0.1 mg/ L and above, the animals showed signs of mild dyspnea with occasional sneezing; intermittent blinking and licking of lips; hyposensitivity to noise; hypersensitivity to touch and aggressive behavior. Decreases in body weight gain were observed in both sexes ( 54 and 49% of control for males and females, respectively).

At 1.0 mg/ L, dyspnea and eye irritation were more severe. Labored movements, increased nasal secretion and polyuria with brown discoloration of the urine were noted during exposures. In several rats, slight coma and body tremors were observed following exposure. Decreases in body weight and body weight gain were observed in both sexes when compared to the control group. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 12 The rats lost weight at this dose level. There was a significant reduction of packed cell volume ( hematocrit), hemoglobin and erythrocyte count and an increase in the number of neutrophils in both sexes. A low mean corpuscular hemoglobin content and decrease in the number of lymphocytes was found in the blood of male rats. There was also a significant reduction in total protein levels in both sexes. In males, a low albumin concentration and a decreased albumin/ globulin ratio were observed. In females, a low urea level and a fall in the alpha and beta fractions of globulins were noted.

No treatment related macroscopic or microscopic lesions were observed at any concentration level.

The LOAEL is 0.1 mg/ L/ day, based on clinical signs of toxicity ( irritation and neurological signs) and decreases in body weight and body weight gain. The NOAEL is 0.01 mg/ L/ day.

This subchronic inhalation toxicity study in the rat is unacceptable non guideline and does not satisfy the guideline requirement for a subchronic inhalation study OPPTS 870.3465; OECD 413 in the rat. It is not upgradable. Since analytical concentrations were not measured and the purity of the test material was not reported, the actual concentration of the test material is unknown.

4.3 Prenatal Developmental Toxicity Adequacy of data base for Prenatal Developmental Toxicity: Although two rat and two rabbit studies have been conducted, the data base for prenatal developmental toxicity is incomplete. A new developmental study in the rabbit is required. Both the developmental toxicity studies in rabbits are unacceptable. In the first rabbit study, at a dose level where decreased body weight gains and abortions were observed in the does, decreased litter size, decreased implantations, increased postimplantation loss, abortions and decreased mean fetal body weight were observed. This study had too few litters, limited data and an unclear method of dosing. No developmental toxicity in rabbits was observed in the repeat study; however, this study was not tested at as high a dose as the first study. It might be possible that developmental toxicity would be observed at a higher dose. This study is classified as unacceptable because of underlying respiratory disease in the does and because of too few litters in two of the treated groups.

No developmental toxicity was observed in either of the two rat studies. The first study was classified as unacceptable because there was very limited data and the dosage period was from gestation days 8 20 which excludes some important gestation days. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 13 870.3700a Prenatal Developmental Toxicity Study  Rat In a developmental toxicity study ( MRID 00029959) amitraz (% a. i and, batch/ lot # not provided) was administered to 11 13 Boots Wistar rats/ dose by gavage ( assumed) in 0.4% cellulose at dose levels of 0, 1, 3, or 12 mg/ kg bw/ day from days 8 through 20 of gestation.

No treatment related maternal effects were observed; however, in a 1 generation reproduction study where rats ( same strain, laboratory and year) were administered the test material by gavage from gestation day 1 through lactation day 21, dams receiving 12 mg/ kg/ day gained 20% less weight than the control group during gestation. Utilizing data from that study ( MRID 00029960), the maternal LOAEL is 12 mg/ kg bw/ day, based on decrease in body weight gain . The maternal NOAEL is 3 mg/ kg bw/ day.

The developmental LOAEL is undetermined. The developmental NOAEL is 12 mg/ kg bw/ day ( HDT).

The developmental toxicity study in the rat is classified unacceptable guideline; and does not satisfy the guideline requirement for a developmental toxicity study ( OPPTS 870.3700; OECD 414) in the rat. Very limited data were provided, the purity of the test substance was not provided and the dosage period was from gestation days 8 20 which excludes some important gestation days.

870.3700a Prenatal Developmental Toxicity Study  Rat In a developmental toxicity study ( MRID 44265902) Amitraz ( 99.7% a. i., batch/ lot # CR 20575/ 3) was administered to three groups of 24 mated female Sprague Dawley Crl: CD( SD) BR rats/ dose in 1% w/ v methyl cellulose in distilled water by gavage at dose levels of 0, 7.5, 15, or 30 mg/ kg bw/ day in 10 mL/ kg bw from days 6 through 15 of gestation. The control group was given the vehicle ( 1% w/ v methylcellulose in distilled water) only.

Maternal toxicity was manifested in the mid and high dose groups by decreases in body weight ( 5% and 8%, respectively), body weight gain ( 11% and 21%, respectively; uterine weights not taken into account) and food consumption ( high dose only, 16% less than controls). At 15 mg/ kg/ day, the decreases in body weight and body weight gain were borderline but were enough to consider 15 mg/ kg/ day as a LOAEL. The maternal LOAEL is 15.0 mg/ kg bw/ day, based on decreases in body weight and body weight gain. The maternal NOAEL is 7.5 mg/ kg bw/ day.

Dilated ureters and renal pelvic cavitation were observed in all groups, including controls. On a fetal basis, an increase in the incidence of dilated ureters was observed at 30 mg/ kg/ day ( 65% compared to 46.4% in the control group, p< 0.01). However, these were observed in 23 litters versus 21 litters in the control group and are thus not considered to be toxicologically significant. Again, on a fetal basis, increases in bilateral renal pelvic cavitation at both 15 and 30 mg/ kg/ day ( 2.9% in controls versus 5.7% and 7.1% at 15 and 30 mg/ kg/ day, respectively) were observed. In AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 14 this case, 6 litters were affected in the control group versus 10 and 11 litters affected at 15 and 30 mg/ kg/ day, respectively. These incidences were not statistically significant, although were likely close to an effect level. When dilated ureters and renal pelvic cavitation grouped together, the incidences are similar to those observed for dilated ureters alone. If the rats had been treated at higher dose levels, it is likely that a clear effect level would have been observed.

The developmental LOAEL is greater than 30 mg/ kg/ day. The developmental NOAEL is 30 mg/ kg/ day.

The developmental toxicity study in the rat is classified Acceptable Guideline and satisfies the guideline requirements for a developmental toxicity study ( OPPTS 870.3700; § 83 3a) in the rat.

870.3700b Prenatal Developmental Toxicity Study  Rabbit In a developmental toxicity study ( MRID 00029961) amitraz (% a. i and, batch/ lot # not provided) was administered to 8 10 New Zealand White rabbits/ dose by gavage ( assumed) in 0.4% cellulose at dose levels of 0, 1, 5, or 25 mg/ kg bw/ day from days 6 through 18 of gestation.

No treatment related maternal effects were observed at either 1 or 5 mg/ kg/ day. At 25 mg/ kg/ day, the does gained less weight than the control group and 4 does aborted. The maternal LOAEL is 25 mg/ kg bw/ day, based on decrease in body weight gain and abortions. The maternal NOAEL is 5 mg/ kg bw/ day.

No treatment related developmental effects were observed at either 1 or 5 mg/ kg/ day. At 25 mg/ kg/ day, decreased litter size, decreased implantations, increased postimplantation loss and decreased mean fetal body weight were observed. The developmental LOAEL is 25 mg/ kg bw/ day, based on decreased litter size, decreased implantations, increased postimplantation loss, abortions and decreased mean fetal body weight. The developmental NOAEL is 5 mg/ kg bw/ day.

The developmental toxicity study in the rabbit is classified unacceptable guideline; and does not satisfy the guideline requirement for a developmental toxicity study ( OPPTS 870.3700; OECD 414) in the rat. Very limited data were provided, there is no indication that gavage dosing was used ( it is assumed), there was a limited number of litters available for analysis ( too few does) and the purity of the test substance was not provided.

870.3700b Prenatal Developmental Toxicity Study  Rabbit In a developmental toxicity study ( MRID 44265901) Amitraz ( 99.7% a. i., batch/ lot # CR 20575/ 3) was administered to three groups of 16 mated female New Zealand White rabbits/ dose in 1% w/ v methyl cellulose in distilled water by gavage at dose levels of 0, 3, 6, or 12 mg/ kg bw/ day in 2 AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 15 mL/ kg bw from days 7 through 19 of gestation. The control group was given the vehicle ( 1% w/ v methylcellulose in distilled water) only.

At 12 mg/ kg/ day, mortality was increased, with two does sacrificed moribund after they aborted their litters. The does lost a mean body weight of 0.06 kg or 2% of the mean body weight early in the dosing period ( between days 7 and 13) during which the control group gained 140 grams ( 4% of the mean body weight). Later in the dosing period ( between days 13 and 19, the 12 mg/ kg/ day group gained 140 grams ( 4% of the mean body weight). Although these values are small when compared to the overall mean weight of the does and no statistical analyses were conducted, it appears that the high dose induces a mild treatment related effect, especially since there is a rebound effect following the dosing period. Food consumption during the treatment period was decreased 26% when compared to controls. Clinical signs included post dosing langor ( 100% of the animals in this group displayed this finding), polypnea ( 94%) and squinting ( 75%). Three of the does totally resorbed their litters. No doe in any other group displayed a total litter resorption. At 6 mg/ kg/ day, post dosing langor ( 94%), polypnea ( 75%) and squinting ( 25%) were observed. At 3 mg/ kg/ day, the same clinical signs were observed: post dosing languor ( 75%), polypnea ( 25%) and squinting ( 13%). These clinical signs were not observed in the control group.

Deaths were observed in all groups, including controls. There was considerable gavage error. Unfortunately, maternal toxicity was confounded by indications that the animals were likely suffering from a respiratory illness throughout the study. The animals appear to have been ill from the start, even in the control group. There was a high incidence of rhinorrhea and fur staining of the paws. Necropsy results revealed a high incidence of abnormal contents in the thoracic cavity and lungs ( colored fluid, white semi solid foci on pleura, other changes) in all groups, including controls. Some of the results from these animals may be attributable to gavage administration.

The maternal LOAEL is 3.0 mg/ kg bw/ day, based on clinical signs in all treated groups. Decreases in body weight gain and food consumption were observed at the highest dose level ( 12 mg/ kg/ day). The maternal NOAEL is not established.

There were no indications of developmental toxicity; however, in two of the treated groups, there were a limited number of litters available for an adequate analysis. The number of available litters ranged from 9 to 14 for each treated and control group. An apparent increase in early resorptions and percent postimplantation loss was seen at 12 mg/ kg/ day; however, these increases were due to the fact that three does at this dose totally resorbed their litters ( 88% of the early resorptions at 12 mg/ kg/ day were found in the three does which displayed total litter resorptions). Examination of body weight gain and food consumption in the animals displaying total litter resorptions indicates that the total litter resorptions were likely due to maternal toxicity rather than a direct effect on the embryo/ fetus.

The developmental LOAEL is greater than 12 mg/ kg bw/ day, the highest dose tested. The developmental NOAEL is 12 mg/ kg bw/ day. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 16 The developmental toxicity study in the rabbit is classified unacceptable guideline and does not satisfy the guideline requirement for a developmental toxicity study ( OPPTS 870.3700; OECD 414) in nonrodents. Deficiencies include: too few litters in two of the treated groups and preexisting maternal illness which may have confounded the results.

4.4 Reproductive Toxicity Adequacy of data base for Reproductive Toxicity: The data base for reproductive toxicity is considered incomplete. Both 1 generation and 3 generation reproduction studies are available. The 1 generation study is unacceptable because it is not a guideline study, it provides limited information and the purity of the test material is unknown. The 3 generation study is considered to be unacceptable because very limited data were provided, mating was not 1 male to 1 female ( only 10 males used/ dose group/ generation), no data on reproductive organs were provided, litter data were only provided for a few time points, and histopathology data were not provided.

870.3800 Reproduction and Fertility Effects  Rat In a 1 generation reproduction study ( MRID 00029960) BTS 27419 ( Amitraz ( purity and batch number not provided) was administered to 13 Boots Wistar rats/ sex/ dose ( 14 in the high dose) by gavage ( assumed) at dose levels of 0,1, 3 or 12 mg/ kg bw/ day in a volume of 1 ml/ 100 g body weight from gestation days 1 through lactation day 21.

At 12 mg/ kg/ day, the dams gained a mean of 20% ( p< 0.001) less weight than the control group. No maternal effects were observed in any other treated group. No information was provided on males. The maternal systemic LOAEL is 12 mg/ kg bw/ day, based on decrease in body weight gain. The maternal systemic NOAEL is 3 mg/ kg bw/ day.

At 12 mg/ kg/ day, there was a slightly lower mean litter size at birth and on lactation day 4 ( p < 0.01). By lactation day 21, mean litter size was comparable to the control group. The offspring LOAEL is 12 mg/ kg bw/ day. The offspring NOAEL is 3 mg/ kg bw/ day. Note: The NOAEL is lower than the original DER because the slightly lower mean litter sizes support the NOAEL, LOAEL and effects observed in the multi generation reproduction study ( MRID 00029962).

No reproductive effects were observed.

This study is unacceptable non guideline and does not satisfy the guideline requirement for a multi generation reproduction study ( OPPTS 870.3800; OECD 416) in the rat. It is only one generation, only provides limited information and does not provide the purity of the test compound.

870.3800 Reproduction and Fertility Effects  Rat AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 17 In a 3 generation reproduction study ( MRID 00029962) BTS 27 419 ( Amitraz ( 99.8% a. i., batch/ lot # 2099DR) was administered to 10 male and 20 female Boots Wistar rats/ dose in the diet at dose levels of 0, 15, 50, or 200 ppm ( equivalent to 0, 1.29, 4.36, or 16.41 mg/ kg bw/ day for males and 1.58, 5.09 or 20.05 mg/ kg bw for females). One litter was produced per generation.

At 16.41/ 20.05 mg/ kg/ day, the F0 parents gained less mean body weight than the control group during the premating period ( 7% in males, 14% in females; statistically significant in females). Body weights were not reported during either the gestation or lactation periods. Body weight values were not measured at this dose level in succeeding generations because of a nearly complete loss of the high dose group during the F1 generation. No other parental effects were observed in any of the treated groups.

The parental systemic LOAEL is 200 ppm ( 16.41 mg/ kg bw/ day in males, 20.05 mg/ kg bw/ day in females), based on decreased body weight gain during the F0 premating period. The parental systemic NOAEL is 50 ppm ( 4.36 mg/ kg bw/ day in males, 5.09 mg/ kg bw/ day in females).

At 16.41/ 20.05 mg/ kg/ day, there was an almost complete loss of pups in the F1 generation during the lactation period ( 5 remaining pups versus 115 remaining pups in the control group). In addition, there was a reduction in mean litter size on day 1 ( 6.7 pups/ litter versus 7.9 pups/ litter in the control group). At 4.36/ 5.09 mg/ kg/ day, in each generation, there was a higher number of pup deaths than in the control group. By day 21, the mean litter size was smaller but was not statistically significantly smaller until the final generation ( p < 0.05).

The offspring LOAEL is 50 ppm ( 4.36/ 5.09 mg/ kg bw/ day), based on decreased survival and mean litter size during lactation. The offspring NOAEL is 15 ppm ( 1.29/ 1.58 mg/ kg bw/ day).

This study is unacceptable guideline and does not satisfy the guideline requirement for a 3 generation reproductive study ( OPPTS 870.3800); OECD 416 in the rat. Very limited data were provided, mating was not 1 male to 1 female ( only 10 males used/ dose group/ generation), no data on reproductive organs were provided, litter data were only provided for a few time points, and histopathology data were not provided. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 18 4.5 Chronic Toxicity Adequacy of data base for chronic toxicity: The data base for chronic toxicity is considered complete. No additional studies are required at this time. Clinical signs, indicative of neurotoxicity were observed in both dogs and rats. In rats, excitable, nervous and aggressive behavior were observed but in dogs, signs of CNS depression and a dose related decrease in body temperature were observed. The dog appears to be the most sensitive species; however, it should be noted that dosing was provided via gelatin capsules in the dog whereas in the rat it was through the diet.

870.4100a ( 870.4300) Chronic Toxicity B Rat In a combined chronic / carcinogenicity study ( MRID 00044585) BTS 27 419 ( 97.8 99.8 % a. i, batch/ lot #' s 2093DH, 2099DH) was administered to 40 Ash Wistar SPF rats/ sex/ dose in the diet at dose levels of 0, 15, 50, or 200 ppm ( equivalent to 0, 0.77/ 0.97, 2.5/ 3.13 or 10.18/ 12.59 mg/ kg bw/ day, males/ females, respectively) for 2 years.

There was no treatment related effect on survival. The number of rats reported as excitable, nervous or aggressive was increased in the 50 ( females) and 200 ppm groups ( males and females); the females were more frequently affected. Body weight gain was decreased in the 200 ppm group at weeks 0 12 for both males and females, weeks 12 24 for females, and weeks 24 36 and 0 104 for males. Food consumption was reduced in both the males and females in the 200 ppm group at the beginning of treatment but then was comparable to the control group. There were no treatment related effects on clinical pathology parameters or necropsy findings. The incidence of tumors was comparable between the treated and control groups. The LOAEL is 200 ppm ( males, 10.18 mg/ kg/ day based on clinical signs and decreased body weight gain) and 50 ppm ( females, 3.13 mg/ kg/ day based on clinical signs). The NOAEL is 50 ppm ( males, 2.5 mg/ kg/ day) and 15 ppm ( females, 0.97 mg/ kg/ day).

At the doses tested, there were no treatment related increases in tumor incidence when compared to controls. Dosing was considered adequate based on clinical signs and decreased body weight gain.

This chronic/ carcinogenicity study in the rat is acceptable guideline and satisfies the guideline requirement for a chronic/ carcinogenicity study OPPTS 870.4300); OECD 453] in the rat.

870.4100b Chronic Toxicity  Dog In a chronic toxicity study ( MRID 00044586) Amitraz ( 97.8 99.8 % a. i. and batch/ lot #' s 2093DH and 2099DH) was administered to 4 beagle dogs/ sex/ dose in gelatin capsules at dose levels of 0, 0.1, 0.25, or 1.0 mg/ kg bw/ day) for 2 years. Clinical signs were monitored; body weight and AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 19 temperature, hematology, clinical chemistry, urinalysis and organ weight parameters were measured; and gross and microscopic examinations were conducted.

At 1.0 mg/ kg/ day, all 8 dogs had CNS depression on the first two days of dosing; however, the data on clinical signs were not submitted. There was a dose related decrease in body temperature after dosing that lasted approximately 6 hours; however, body temperatures essentially remained in the normal range. The LOAEL is 1.0 mg/ kg/ day, based on CNS depression during the first two days of dosing. The NOAEL is 0.25 mg/ kg/ day.

This chronic study in the dog is acceptable guideline and satisfies the guideline requirement for a chronic oral study [ OPPTS 870.4100, OECD 452] in the dog.

4.6 Carcinogenicity Adequacy of data base for Carcinogenicity: The data base for carcinogenicity is considered complete. No additional studies are required at this time. Amitraz is not carcinogenic in the rat under the conditions of the study; however, it is considered to be carcinogenic in the mouse, inducing hepatocellular adenomas, carcinomas and combined adenomas and/ or carcinomas in females and lung adenomas in males. Dose levels were considered to be adequate in both studies.

870.4200a Carcinogenicity Study  rat See 870.4100a ( 870.4300) Chronic Toxicity B Rat 870.4200b Carcinogenicity ( feeding)  Mouse In a carcinogenicity study ( MRID 00139552) Amitraz ( 88.2 100.8% a. i., batch #' s 34732Y, 52221, 56105) was administered to 100 control and 75 treated B6C3F1 mice/ sex/ dose in the diet at dose levels of 0, 25, 100 or 400 ppm ( equivalent to 0, 2.31/ 2.63, 9.61/ 10.77, or 44.65/ 50.13 mg/ kg bw/ day) for 104 weeks.

At 2.31/ 2.63 mg/ kg/ day and above, a dose related increase in the incidence of hyperplastic nodules, basophilic and telangiectatic foci was observed in the liver of females, accompanied by an increased incidence of stomach hyperkeratosis and spleen hematopoiesis in males.

At 9.61/ 10.77 mg/ kg/ day and above, hyperactivity and aggressive behavior were observed in males during the first 12 weeks of the study. Cutaneous lesions, as evidence of fighting were also observed. By week 52, mean body weight gain was reduced by 29% in males and 32% in females ( p< 0.01). A 6% decrease in food consumption was observed in males during weeks 1 12 at both the mid and high dose levels ( p< 0.05) and during weeks 13 25 at the mid dose level ( p< 0.01). An increase in food consumption was recorded at the high dose level in males during weeks 26 104 ( 9 13%). In females, 5 11% decreases in food consumption were observed during weeks 1 19 AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 20 ( p< 0.05), followed by increases in food consumption during weeks 31 58 and 93 104. The bone marrow myeloid/ erythroid ratio was significantly reduced ( p< 0.001) in females ( 22% and 26% at the mid and high dose levels, respectively).

At 44.65/ 50.13 mg/ kg/ day, piloerection and hunched posture were observed in males during weeks 2 4. Food utilization was lower for both sexes during the first 24 weeks of the study ( approximately 35% 42% lower). Mean body weight gain was reduced by week 52 in males and females ( 29% and 32%, respectively, p< 0.01). The bone marrow myeloid/ erythroid ratio was significantly reduced ( p< 0.001) in males ( 24%).

Males had a significant positive trend in mortality with incremental doses of amitraz.

The LOAEL is 2.31/ 2.63 mg/ kg/ day, based on a dose related increase in the incidence of hyperplastic nodules, basophilic and telangiectatic foci in the liver of females, accompanied by an increased incidence of stomach hyperkeratosis and spleen hematopoiesis in males. The NOAEL is less than 2.31/ 2.63 mg/ kg/ day.

In females there were significant dose related positive trends in hepatocellular adenomas, carcinomas and in combined adenomas/ carcinomas. Females also had a significant increase in the pair wise comparison of controls and the highest dose group in hepatocellular adenomas, carcinomas and in combined adenomas and/ or carcinomas. Males had a significant dose related positive trend in lung adenomas. In addition, males had a significant increase in the pair wise comparison of controls and the highest dose group in lung adenomas. Reduction in body weight gain and a significant positive trend in mortality in male mice suggest that the highest dose tested was excessive. In females, however, the highest dose was high but not excessive since it was not life threatening.

This carcinogenicity study in the mice is acceptable guideline and satisfies the guideline requirement for a carcinogenicity study [ OPPTS 870.4200; OECD 451] in mice.

4.7 Mutagenicity Adequacy of data base for Mutagenicity: The data base for mutagenicity is considered adequate based on the 1991 mutagenicity guidelines. Amitraz does not appear to be mutagenic under the conditions of the assays in which it was tested: reverse mutation in Salmonella typhimurium ( Ames), forward mutation in mouse lymphoma cells, in vitro structural chromosome aberration assay in human lymphocytes and in a cell transformation assay in C3H/ 10T1/ 2 cells derived from mouse embyro fibroblasts.

Gene Mutation AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 21 Guideline # 870.5100, Salmonella reverse gene mutation ( Ames) MRID 00161009 Acceptable Guideline Dose range: 33

g/ plate to 10 mg/ plate Negative up to 10 mg/ plate, with or without metabolic activation.

Guideline # 870.5300, Forward Gene Mutation Assay ( mouse L5178Y lymphoma cells) MRID 00161008 Acceptable Guideline Negative at 0.06 20

g/ ml with and without activation. HDT is highest non cytotoxic dose.

Cytogenetics Guideline # 870.5375, In vitro Structural Chromosome Aberration Assay ( human lymphocytes) MRID 41795101 Acceptable Guideline Dose range: 5  20

g/ ml without metabolic activation and 3  30

g/ ml with activation Negative up to cytotoxic and/ or insoluble concentrations.

Other Genotoxicity Guideline # 870.5550 UDS Assay ( Human Embryonic Lung Fibroblast) MRID 00161011 Acceptable Guideline Dose range: 20  300

g/ ml Negative up to cytotoxic concentrations, with and without metabolic activation.

Guideline # N/ A Morphological Transformation ( C3H/ 10T1/ 2 cells derived from mouse embyro fibroblast) MRID 00161010 Acceptable Guideline Dose range: 12.5  37.5

g/ ml with S 9; 5  15

g/ ml without S 9. Negative up to cytotoxic concentrations, with and without activation. MRID 00161010 4.8 Neurotoxicity Adequacy of data base for Neurotoxicity: No neurotoxicity studies have been conducted. Evidence of neurotoxicity following exposure to Amitraz is indicated in multiple studies across species. In both the subchronic and chronic oral studies in dogs, signs of CNS depression were observed and a decrease in pulse rate and hypothermia were noted in the subchronic study. In both the subchronic and chronic oral studies in the rat, irritability, nervousness and/ or excitability were observed. In the rabbit developmental toxicity study, clinical signs that were considered to be related to treatment included langor and polypnea. These signs could be evidence of neurotoxicity. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 22 870.6100 Delayed Neurotoxicity Study  Hen A delayed neurotoxicity study in the hen has not been conducted. This study is not currently required for amitraz.

870.6200 Acute Neurotoxicity Screening Battery An acute mammalian neurotoxicity study has not been conducted.

870.6200 Subchronic Neurotoxicity Screening Battery A subchronic mammalian neurotoxicity study has not been conducted.

870.6300 Developmental Neurotoxicity Study A developmental neurotoxicity study has not been conducted.

4.9 Metabolism Adequacy of data base for metabolism: The data base for metabolism is considered to be complete. No additional studies are required at this time. Extensive metabolism studies have been conducted with amitraz in several species, including humans, baboons, dogs, rats, and mice. In all species, amitraz was rapidly hydrolyzed in the stomach, following oral administration, to form at least six metabolites. Metabolites BTS 27,271 ( N( 2,4 dimethylphenyl) N methylformamidine) and 27919 ( 2,4 dimethylformanilide), both of which are formed via hydrolysis at the C N [ Nmethylmethanimidamide bond) are the primary metabolites of amitraz. Excretion of metabolites occurred mainly in the urine over 48 hours ( 62% 82% in all species) and to a lesser extent in feces ( 9% 39%), with no unchanged parent compound observed in urine. The proportion of various metabolites recovered in the urine of all species was also similar. The highest levels of 14C tissue residues in animals were found in the liver, bile, kidney, adrenal glands, and pigmented areas of the eye over 3 to 4 days. The executive summar of the most representative metabolism studies are summarized in the following paragraphs.

870.7485 Metabolism  Rat Two male and two female Sprague Dawley rats ( 135 250g) per dose level were administered a single dose of radiolabeled 14C amitraz in corn oil by gavage 1, 10 or 100 mg/ kg body weight ( MRID 00161004). Twenty four hour collections of urine samples were subjected to metabolite isolation and identification. No sex differences were apparent in the proportion of the various metabolites recovered in the 24 hour urine samples. The metabolic process was saturated at the 100 mg/ kg level. The proportion of BTS27271 increased with a corresponding decrease in the amount of polar material observed at the 100 mg/ kg level. At the 10 mg/ kg level and below, a AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 23 decrease in the amount of BTS27271 and an increase in the polar fraction was reported. No unchanged parent material ( BTS 27419) was found in the urine. The major metabolites were N ( 2,4 dimethylphenyl) N methyl formamidine ( BTS 27271), 4 formamido 3 methyl benzoic acid ( BTS 39098), 4 acetamido 3 methyl benzoic acid ( FBC 31158) and a polar fraction. The polar fraction was labile to acid hydrolysis, yielding conjugates of 4 amino 3 methylbenzoic acid ( BTS 28369), N( 2,4 dimethylphenyl) N methyl formamidine ( BTS 27271), 4 formamido 3 methyl benzoic acid ( BTS 39098) and 4 acetamido 3 methyl benzoic acid ( BTS 31158).

Amitraz ( 94%), labeled ( 14C) in the  2 methyl position and the metabolite, BTS 27271, labeled ( 14C) in the phenyl ring were each administered by gavage at a dose level of 5.0 mg/ kg body weight to two male Sprague Dawley rats ( 150 200g; Knowles and Benezet). The rats were placed in metabolism cages for collection of urine and feces at 3, 8, 12, 24, 48 and 96 hours. Tissue equivalents ( ppb) of amitraz and BTS 27271 were determined in brain, heart, intestine, kidney, liver, lung, spleen and blood. Peak levels of amitraz elimination in the urine were reached within 8 hours with 78% of the dose accounted for in the urine and 9% in the feces by 98 hours. Peak levels of BTS 27271 in the urine were reached within 24 hours with 89% accounted for in the urine and 4% in the feces by 96 hours. The highest residues of amitraz and BTS 27271 were reported in the liver at 137.7 and 182.6 ppb, respectively. Blood residue levels were 17.9 ppb for amitraz and not detectable for BTS 27271. Kidney residue levels were comparable with 18.0 and 24 ppb for amitraz and BTS 27271, respectively. Degradation products of amitraz and it's metabolite, BTS 27271 were similar.

870.7600 Dermal Absorption  Rat Ten male rats were dosed via the dermal route with the M82 formulation of amitraz diluted in water at a dose of 91 micrograms/ cm2 a. i. ( MRID 42133501). The application site was shaved and washed with acetone 24 hours before dosing. After dosing the site was protected with a nonocclusive device and the animals were placed individually in metabolism cages for collection of total urine and feces. After ten hours of exposure, the application site of each animal was washed quantitatively with soap and water and the animals were returned to metabolism cages. At 24 hours post dosing, 5 animals were euthanized and the application site skin, digestive tract and the remaining carcass were collected for analysis. The remaining five animals were carried for five days postdosing, with total urine and fecal samples for each 24 hour period, and then terminated as above. The mean percent of dose available for risk assessment purposes is shown in the following table. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 24 Dermal Absorption Study in Rats: Mean Percent of Dose Available for Risk Assessment 24 Hours (%) 120 Hours (%)

Treatment Site 2.98 1.41 Total Absorbed 3.69 6.56 Total 6.67 7.79 5.0 TOXICITY ENDPOINT SELECTION 5.1 See Section 9.2 for Endpoint Selection Table.

5.2 Dermal Absorption Dermal Absorption Factor: 8 % from a dermal absorption study the M82 formulation of amitraz diluted in water at a dose of 91 micrograms/ cm2 a. i. in the rat The dermal absorption factor is required for dermal risk assessments ( all durations) since oral doses were selected for these exposure periods.

5.3 Classification of Carcinogenic Potential 5.3.1 Amitraz was not found to be a carcinogen in rats under the conditions of the study. In female mice there were significant dose related positive trends in hepatocellular adenomas, carcinomas and in combined adenomas/ carcinomas. Females also had a significant increase in the pair wise comparison of controls and the highest dose group in hepatocellular adenomas, carcinomas and in combined adenomas and/ or carcinomas. Male mice had a significant doserelated positive trend in lung adenomas. In addition, males had a significant increase in the pairwise comparison of controls and the highest dose group in lung adenomas.

5.3.2 Classification of Carcinogenic Potential The HED Cancer Peer Review Committee met on October 31, 1990 and determined that Amitraz should be classified as a Group C, possible human carcinogen.

5.3.3 Quantification of Carcinogenic Potential The Q 1* was calculated to be 2.83 x 10 2 in human equivalents, based upon the combined hepatocellular adenomas and carcinomas in female mice. A 3/ 4' s cross species scaling factor was utilized for the calculation. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 25 6.0 FQPA CONSIDERATIONS 6.1 Special Sensitivity to Infants and Children The HIARC cannot conclude whether or not there is any concern for pre and/ or postnatal toxicity resulting from exposure to Amitraz because neither the rabbit developmental nor the rat reproduction studies are acceptable and they have too many deficiencies.

There is no evidence ( quantitative or qualitative) of increased susceptibility following pre natal exposure to rats. However, evidence for susceptibility following pre natal exposure to rabbits or following pre and/ or postnatal exposure to rats could not be ascertained due to many deficiencies in study designs and/ or study reports.

There are no concerns for residual uncertainty for pre natal toxicity in the available developmental toxicity study in rats.

The HIARC determined that despite the lack of acceptable rabbit developmental and rat reproduction studies, there are no residual uncertainties for pre and/ or post natal toxicity based on the following considerations:

° Although susceptibility could not be ascertained in rabbits, the results of the two unacceptable studies show that developmental effects occurred at doses higher than the doses that caused maternal toxicity.

° A 10X database uncertainty factor ( UF DB) is required due to an incomplete database ( i. e. lack of acceptable rabbit developmental toxicity and two generation reproduction studies).

° At present, the endpoint of concern ( neurotoxicity) for the overall risk assessment is based on the " apparent" sensitive species ( dogs).

° The dose ( 0.25 mg/ kg/ day) selected for the overall risk assessments is approximately 20 fold lower than the lowest developmental NOAEL in the unacceptable rabbit studies and 5 fold lower than the offspring NOAEL in the unacceptable three generation reproduction study.

Based on the above data, no special FQPA safety factor ( i. e. 1X) is required since there are no residual uncertainties for pre natal toxicity as discussed above.

The Special FQPA Safety Factor recommended by the HIARC assumes that the exposure databases ( dietary food, drinking water, and residential) are complete and that the risk assessment for each potential exposure scenario includes all metabolites and/ or degradates of concern and does not underestimate the potential risk for infants and children AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 26 6.2 Recommendation for a Developmental Neurotoxicity Study The HIARC concluded that there is concern for developmental neurotoxicity resulting from exposure to Amitraz.

A. Evidence that suggest requiring a Developmental Neurotoxicity study:

° The available toxicity database indicates that clinical signs of CNS toxicity are observed in rats, dogs and possibly rabbits.

B. Evidence that do not support a need for a Developmental Neurotoxicity study:

° None.

Based on the weight of evidence presented, the HIARC is requiring a combined 2 generation reproduction study in the rat with components assessing for potential developmental and adult neurotoxicity. The HIARC recommended that the study design for the required two generation reproduction study should be MODIFIED to include the following:

° Due to the concern for the lack of stability of the test material in the diet, treatment should be via oral ( gavage) administration.

° The potential for neurotoxicity in the developing fetuses should be evaluated according to the OPPTS Guideline § 870.6300.

° The potential for neurotoxicity in adults should be evaluated according to the OPPTS Guideline § 870.6200.

The HIARC determined that the 10X UF DB should be applied to dietary ( acute and chronic) and non dietary ( incidental oral, dermal and inhalation) risk assessments because the required studies may provide endpoints applicable for risk assessments.

7.0 OTHER ISSUES Amitraz is not stable in the diet ( TXR Nos. 012646 and 005633). The current endpoints are based on a gavage study. In the dietary studies, due to significant degradation, the animals are likely more exposed to the degradation products than to the parent. These degradation products also happen to be significant animal and plant metabolites. Therefore, in the diet, humans are more likely to be exposed to the degradation product than to the parent. The dermal and inhalation endpoints are also based on a gavage study. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 27 Since it is possible that humans may more likely be exposed to the technical material via the dermal and inhalation routes because they will be directly exposed without a chance for significant degradation, the gavage study may be more appropriate as the study of choice for these routes ( the dermal and inhalation studies are not acceptable).

8.0 REFERENCES 00029959 Sutton, M. M. ( 19??) BTS 27 419: Teratogenicity in the Rat: Report No. TX 73028. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 I)

00029960 Sutton, M. M. ( 19??) BTS 27 419: Effect on Pregnancy, Parturition and Care of the Young in Rats: Report No. TX 73031. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 J)

00029961 Sutton, M. M. ( 19??) BTS 27 419: Teratogenicity in the Rabbit: Report No. TX 73029. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 K)

00029962 Sutton, M. M. ( 19??) BTS 27 419: Multigeneration Feeding Test in Rats: Report No. TX 73036. ( Unpublished study received Apr 9,1980 under 43142 EX 1; submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 L)

00029963 Berczy, Z. S.; Binns, R.; Newman, A. J. ( 1972) Acute Inhalation Toxicity to the Rat of BTS 27419: Report No. 4971/ 72/ 406. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; prepared by Huntingdon Research Centre, submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 M)

00029964 Berczy, Z. S.; Binns, R.; Street, A. E.; et al. ( 1973) Subacute Inhalation Toxicity to the Rat of BTS 27419: Report No. 5454/ 72/ 850. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; prepared by Huntington Research Centre, submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 N)

00029965 Sutton, M. M. ( 1971) BTS 27 419: Contact Sensitisation ? sic| in the Guinea Pig. ( Unpublished study received Apr 9, 1980 under 43142 EX 1; submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 O)

00029972 Sutton, M. M. ( 1977) BTS 27 419: Three Week Dermal Toxicity to Rabbits: Report No. TX 73026. ( Unpublished study received Apr 9,1980 under 43142 EX 1; AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 28 submitted by Boots Hercules Agrochemicals Co., Wilmington, Del.; CDL: 099368 V)

00040345 Patton, D. S. G.; Williams, G. A. H. ( 1973) BTS 27 419: 90 Day Toxicity Study in Dogs: P 71547. ( Unpublished study received Oct 7, 1974 under 5G1558; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 094252 AN)

00040861 Sutton, M. M.; Metcalf, W. ( 1972) BTS 27 419. Eye Irritancy in the Rabbit: TXM72037. ( Unpublished study received Oct 7, 1974 under 5G1558; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 094254 H)

00040862 Sutton, M. M.; Williams, P. A. ( 1972) BTS 27 419: Acute Dermal Toxicity to Rabbits: YM72011. ( Unpublished study received Oct 7,1974 under 5G1558; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 094254 I)

00041539 Shaw, J. W. ( 1973) BTS 27 419: Acute Oral Toxicity to Male and Female Rats: TXM 73041. ( Unpublished study received Jun 24, 1976 under 6F1817; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 096419 AE)

00044585 Sutton, M. M.; Offer, J. ( 1973) BTS 27 419: Carcinogenicity and Long Term Toxicity Study in Rats: Report TX 73043. ( Unpublished study received Jun 24, 1976 under 6F1817; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 096417 A)

00044586 Morgan, H. E.; Patton, D. S. G.; Turnbull, G. J. ( 19??) BTS 27 419: Two Year Oral Toxicity Study in Dogs: TX 73035. ( Unpublished study received Jun 24, 1976 under 6F1817; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 096415 A)

00051784 Sutton, M. M.; Williams, G. A. H. ( 1971) BTS 27 419: 90 Day Toxicity Study in Rats. ( Unpublished study received Jun 24, 1976 under 6F1817; submitted by Upjohn Co., Kalamazoo, Mich.; CDL: 096418 A)

00139552 Colley, J.; Dawe, S.; Heywood, R.; et al. ( 1983) Amitraz: 104 Week Tumorigenicity Study in Mice: HRC Report No. BTS 153/ 8262/ A; T233. Final report. ( Unpublished study received Jan 5, 1984 under 1023 59; prepared by FBC, Ltd., Eng., submitted by Upjohn Co., Kalamazoo, MI; CDL: 252098 A; 252099; 252100; 252101; 252102)

00161004 Campbell, J.; Needham, D. ( 1984) The Metabolism of [ Carbon 14] Amitraz by Male and Female Rats: Study No. 3L: Report No. METAB/ 84/ 2. Unpublished study prepared by FBC Ltd., Chesterford Park Research Station. 32 p. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 29 00161008 McGregor, D.; Riach, C. ( 1983) Technical Amitraz: Mouse Lymphoma Mutation Assay: IRI Project No. 730923: Report No. 2669. Unpublished FBC Study No. TOX 83016 prepared by Inveresk Research International. 48 p.

00161009 McGregor, D.; Prentice, R. ( 1983) Technical Amitraz: Ames Bacterial Mutagenicity Test: IRI Project No. 730918: Report No. 2590. Unpublished FBC Study No. TOX 83015 prepared by Inveresk Research International. 25 p.

00161010 McGregor, D.; Riach, C. ( 1983) Technical Amitraz: Induction of Morphological Transformation in C3H/ 10T1/ 2 Cells: IRI Project No. 730698: Report No. 2625. Unpublished FBC Study No. TOX 83001 prepared by Inveresk Research International. 23 p.

00161011 McGregor, D.; Riach, C. ( 1983) Technical Amitraz: Unscheduled DNA Synthesis in Human Embryonic Cells: IRI Project No. 730703: Report No. 2634. Unpublished FBC Study No. TOX 83002 prepared by Inveresk Research International. 19 p.

41795101 Brooker, P.; Akhurst, L.; Gray, V. ( 1988) T300 Technical Amitraz Metaphase Chromosome Analysis of Human Lymphocytes Cultured in vitro: Lab Project Number: TOX/ 88/ 179 154. Unpublished study prepared by Huntingdon Research Centre. 23 p.

42133501 Challis, I. ( 1990) M82 Amitraz: Dermal Absorption of Amitraz in the Rat: Lab Project Number: TOX/ 90/ 179 178. Unpublished study prepared by Schering Agrochemicals Ltd. 41 p.

44265901 McIntyre, M. ( 1987) Technical Amitraz: Teratogenicity Study in the Rabbit: Lab Project Number: 5536 194/ 13: TOX/ 86157: 194/ 13. Unpublished study prepared by Hazleton UK. 124 p.

44265902 McIntyre, M. ( 1987) Technical Amitraz: Teratogenicity Study in the Rat: Lab Project Number: 5562 194/ 11: TOX/ 86156: T 279. Unpublished study prepared by Hazleton UK. 121 p.

No MRID Knowles, C. O. and H. J. Benezet. ( 1981) Excretion Balance, Metabolic Fate and Tissue Residue Following Treatment of Rats with Amitraz and N'( 2,4 Dimethylphenyl) N Methylformanidine ( BTS 27271). J. Environ. Sci. Health B16( 5), 547 555. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 30 9.0APPENDICES Tables for Use in Risk Assessment AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 31 9.1 Toxicity Profile Summary Tables 9.1.1 Acute Toxicity Table  See Section 4.1 9.1.2 Subchronic, Chronic and Other Toxicity Tables Guideline No./ Study Type MRID No. ( year)/ Classification / Doses Results 870.3100 90 Day oral toxicity rodents 00051784 ( 1971) Unacceptable Guideline 0, 3, 12, 50, 200 mg/ kg/ day by gavage NOAEL = 3 mg/ kg/ day LOAEL = 12 mg/ kg/ day based on irritability, excitability and reduced overall body weight gain. No individual animal data for clinical signs and gross necropsy.

870.3150 90 Day oral toxicity in dogs 00040345 ( 1973) Unacceptable Guideline 0, 0.25, 1.0, 4.0 mg/ kg/ day ( capsules) NOAEL = 0.25 mg/ kg/ day LOAEL = 1.0 mg/ kg/ day based on CNS depression, decrease in pulse rate, increase in glucose in urine, hypothermia, neutrophilia of bone marrow, increased liver weights and increased extent of liver lesions. Too few animals.

870.3200 21/ 28 Day dermal toxicity 00029972 ( 1973) Unacceptable Guideline 0, 50 200 mg/ kg/ day NOAEL = Cannot be determined LOAEL = 50 mg/ kg/ day based on clinical signs ( sedation) and a decrease in food consumption in males. Too few animals, concurrent infections, lack of information on the substance tested and limited histopathology.

870.3465 90 Day inhalation toxicity 00029964 ( 1973) Unacceptable Non guideline 0, 0.01, 0.1, 1.0 mg dust/ L; 6 hrs/ day for 14 days over a period of 3 weeks. NOAEL = 0.01 mg/ L/ day LOAEL = 0.1 mg/ L/ day ( nominal) based on clinical signs of toxicity ( irritation and neurological signs) and decreases in body weight and body weight gain. Limited individual animal data; analytical exposure concentrations not measured; purity of test material not reported and reporting incomplete in terms of the study protocol and environmental conditions. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Guideline No./ Study Type MRID No. ( year)/ Classification / Doses Results 32 870.3700a Prenatal developmental in rats 00029959 ( 1973) Unacceptable Guideline 0, 1, 3, or 12 mg/ kg/ day: GD days 8  20 Maternal NOAEL = 3 mg/ kg/ day LOAEL = 12 mg/ kg/ day based on decreases in body weight gain. Developmental NOAEL = 12 mg/ kg/ day LOAEL = > 12 mg/ kg/ day [ HDT]. Very limited data, dosage period was from gestation days 8 20.

870.3700a Prenatal developmental in rats 44265902 ( 1987) Acceptable Guideline 0, 7.5, 15 or 30 mg/ kg/ day Maternal NOAEL = 7.5 mg/ kg/ day LOAEL = 15.0 mg/ kg/ day based on decreases in body weight and body weight gain. Developmental NOAEL = 30 mg/ kg/ day LOAEL = > 30 mg/ kg/ day [ HDT].

870.3700b Prenatal developmental in rabbits 00029961 ( 1973) Unacceptable Guideline 0, 1, 5, 25 mg/ kg/ day Maternal NOAEL = 5 mg/ kg/ day LOAEL = 25 mg/ kg/ day based on decrease in body weight gain and abortions Developmental NOAEL = 5 mg/ kg/ day LOAEL = 25 mg/ kg/ day based on decreased litter size, decreased implantations, increased postimplantation loss, abortions and decreased mean fetal body weight. Too few litters, limited data, unclear method of dosing.

870.3700b Prenatal developmental in rabbits 44265901 ( 1987) Unacceptable Guideline 0, 3, 6, 12 mg/ kg/ day Maternal NOAEL = not established LOAEL = 3.0 mg/ kg/ day based on clinical signs. Developmental NOAEL = 12 mg/ kg/ day LOAEL = > 12 mg/ kg/ day ( HDT). Too few litters in two treated groups and pre existing maternal respiratory infections. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Guideline No./ Study Type MRID No. ( year)/ Classification / Doses Results 33 870.3800 Reproduction and fertility effects ( 1 generation) 00029960 ( 1973) Unacceptable, Non guideline 0,1, 3 or 12 mg/ kg/ day from GD 1  lactation day 21. Parental/ Systemic NOAEL = 3 mg/ kg/ day LOAEL = 12 mg/ kg/ day based on decreased body weight gain. Reproductive NOAEL = 12 mg/ kg/ day LOAEL > 12 mg/ kg/ day ( HDT). Offspring NOAEL = 3 mg/ kg/ day LOAEL = 12 mg/ kg/ day based on lower mean litter size at birth and on lactation day 4.

870.3800 Reproduction and fertility effects ( 3 generations) 00029962 ( 1973) Unacceptable Guideline 0, 1.29/ 1.58, 4.36/ 5.09, 16.41/ 20.05 mg/ kg/ day ( M/ F) Parental/ Systemic NOAEL = 4.36/ 5.09 ( M/ F) mg/ kg/ day LOAEL = 16.41/ 20.05 ( M/ F) mg/ kg/ day based on decreased body weight gain during the F0 premating period.. Reproductive NOAEL = 16.41/ 20.05 ( M/ F) mg/ kg/ day LOAEL > 16.41/ 20.05 ( M/ F) mg/ kg/ day ( HDT). Offspring NOAEL = 1.29/ 1.58 ( M/ F) mg/ kg/ day LOAEL = 4.36/ 5.09 ( M/ F) mg/ kg/ day based on decreased survival and mean litter size during lactation. Limited data provided, mating was not 1 male to 1 female, no data on reproductive organs provided, litter data only provided for a few time points, and histopathology data not provided.

870.4100b Chronic toxicity dogs 00044586 ( 1973) Acceptable Guideline 0, 0.1, 0.25, 1.0 mg/ kg/ day ( capsule) NOAEL = 0.25 mg/ kg/ day LOAEL = 1.0 mg/ kg/ day based on CNS depression during first two days of dosing.

870.4300 Chronic Toxicity/ Carcinogenicity rats 00044585 ( 1973) Acceptable Guideline 0, 0.77/ 0.97, 2.5/ 3.13, 10.18/ 12.59 mg/ kg/ day ( M/ F) NOAEL = 2.5/ 0.97 ( M/ F) mg/ kg/ day LOAEL = 10.18/ 3.13 ( M/ F) mg/ kg/ day based on clinical signs ( M and F) and decreased body weight gain ( M). No evidence of carcinogenicity. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Guideline No./ Study Type MRID No. ( year)/ Classification / Doses Results 34 870.4300 Carcinogenicity mice 00139552 ( 1983) Acceptable Guideline 0, 2.31/ 2.63, 9.61/ 10.77, 44.65/ 50.13 mg/ kg/ day ( M/ F) NOAEL = < 2.31/ 2.63 ( M/ F) mg/ kg/ day LOAEL = 2.31/ 2.63 ( M/ F) mg/ kg/ day based on dose related incidence of hyperplastic nodules, liver foci, stomach hyperkeratosis and spleen hematopoiesis. Evidence of carcinogenicity: hepatocellular adenomas, carcinomas and combined; and lung adenomas, probably at dose levels above MTD.

Reverse Gene Mutation in Salmonella typhimurium 870.5100 00161009 ( 1983) Acceptable Guideline 33, 100 and 333

g/ plate and 1, 3.3 and 10 mg/ plate Negative up to 10 mg/ plate, with and without metabolic activation.

Forward Gene Mutation in mouse lymphoma cells 870.5300 00161008 ( 1983) Acceptable Guideline 0.06, 0.2, 0.6, 2, 6 or 20

g/ ml Negative at 0.06 20

g/ ml with and without metabolic activation. HDT is highest noncytotoxic dose.

In Vitro Cytogenetics ( Human Lymphocytes) 870.5375 41795101 ( 1988) Acceptable Guideline 5, 10, 20

g/ ml without metabolic activation and 3, 15, 30

g/ ml with activation Negative up to cytotoxic and/ or insoluble concentrations.

UDS Assay ( Human Embryonic Lung Fibroblast) 870.5550 00161011 ( 1983) Acceptable Guideline 20, 60, 100, 140, 180, 220, 260, 300

g/ ml Negative up to cytotoxic concentrations, with and without metabolic activation.

Cell Transformation ( no guideline #) 00161010 ( 1983) Acceptable Nonguideline 12.5, 25 and 37.5

g/ ml with S 9; 5, 10 and 15

g/ ml without S 9. Negative up to cytotoxic concentrations, with and without metabolic activation. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Guideline No./ Study Type MRID No. ( year)/ Classification / Doses Results 35 870.7485 Metabolism and pharmacokinetic s MRID 00161004 ( 1984)/ Acceptable No sex differences in proportion of various metabolites recovered in 24 hour urine samples. Metabolic process saturated at the 100 mg/ kg level. No unchanged parent material found in the urine. Major metabolites: N( 2,4 dimethylphenyl) Nmethyl formamidine, 4 formamido 3 methyl benzoic acid, 4 acetamido 3 methyl benzoic acid and a polar fraction. The polar fraction was labile to acid hydrolysis, yielding conjugates of 4 amino 3 methylbenzoic acid, N( 2,4 dimethylphenyl) N methyl formamidine, 4 formamido 3 methyl benzoic acid and 4 acetamido 3 methyl benzoic acid.

870.7485 Metabolism and pharmacokinetic s No MRID: Knowles, C. O. and H. J. Benezet. ( 1981) / Acceptable Peak levels of amitraz reached in urine within 8 hours: 78% of the dose in the urine and 9% in the feces by 98 hours. Peak levels of metabolite BTS 27271 reached in urine within 24 hours: 89% of the dose in the urine and 4% in the feces by 96 hours. Highest residues of amitraz and BTS 27271 reported in the liver. Blood residue levels were 17.9 ppb for amitraz and not detectable for BTS 27271. Kidney residue levels were comparable with 18.0 and 24 ppb for amitraz and BTS 27271, respectively. Degradation products of amitraz and its metabolite, BTS 27271 were similar.

870.7600 Dermal penetration MRID 42133501 ( 1990)/ Acceptable The mean percent of dose absorbed: treatment site ( 2.98% at 24 hours, 1.41% at 120 hours); total absorbed ( 3.69% at 24 hours, 6.56% at 120 hours); total ( 6.67% at 24 hours, 7.79% at 120 hours). AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter 36 9.2 Summary of Toxicological Dose and Endpoints for Amitraz for Use in Human Risk Assessment Exposure Scenario Dose Used in Risk Assessment, UF Special FQPA SF* and Level of Concern for Risk Assessment Study and Toxicological Effects Acute Dietary ( General population including infants and children) NOAEL = 0.25 mg/ kg/ day UF = 1000 Acute RfD = 0.00025 mg/ kg/ day FQPA SF = 1 aPAD = acute RfD FQPA SF = 0.00025 mg/ kg/ day Chronic oral study in the dog ( capsule) LOAEL = 1.0 mg/ kg/ day based on CNS depression during the first two days of dosing.

Chronic Dietary ( All populations) NOAEL= 0.25 mg/ kg/ day UF = 1000 Chronic RfD = 0.00025 mg/ kg/ day FQPA SF = 1 cPAD = chronic RfD FQPA SF = 0.00025 mg/ kg/ day Chronic oral study in the dog ( capsule) LOAEL = 1.0 mg/ kg/ day based on CNS depression during the first two days of dosing.

Short and Intermediate  Term Incidental Oral ( 1 30 days and 1 6 months) NOAEL= 0.25 mg/ kg/ day Residential LOC for MOE = 1000 Occupational = NA Chronic oral study in the dog ( capsule) LOAEL = 1.0 mg/ kg/ day based on CNS depression during the first two days of dosing.

Dermal ( All Durations) Oral NOAEL = 0.25 mg/ kg/ day ( dermal absorption rate 8%) Residential LOC for MOE = 1000 Occupational LOC for MOE = 100 Chronic oral study in the dog ( capsule) LOAEL = 1.0 mg/ kg/ day based on CNS depression during the first two days of dosing.

Inhalation ( All Durations) Oral NOAEL= 0.25 mg/ kg/ day ( inhalation absorption rate = 100%) Residential LOC for MOE = 1000 Occupational LOC for MOE = 100 Chronic oral study in the dog ( capsule) LOAEL = 1.0 mg/ kg/ day based on CNS depression during the first two days of dosing. AMITRAZ/ MARCH/ 2004 RED Toxicology Chapter Exposure Scenario Dose Used in Risk Assessment, UF Special FQPA SF* and Level of Concern for Risk Assessment Study and Toxicological Effects 37 Cancer ( oral, dermal, inhalation) Q1* = 2.83 x 10 2 Group: C Combined hepatocellular adenomas and carcinomas in female mice.

UF = uncertainty factor, FQPA SF = Special FQPA safety factor, NOAEL = no observed adverse effect level, LOAEL = lowest observed adverse effect level, PAD = population adjusted dose ( a = acute, c = chronic) RfD = reference dose, MOE = margin of exposure, LOC = level of concern, NA = Not Applicable NOTE: The Special FQPA Safety Factor recommended by the HIARC assumes that the exposure databases ( dietary food, drinking water, and residential) are complete and that the risk assessment for each potential exposure scenario includes all metabolites and/ or degradates of concern and does not underestimate the potential risk for infants and children.


[Federal Register Volume 85, Number 231 (Tuesday, December 1, 2020)]
[Notices]
[Pages 77212-77213]
[FR Doc No: 2020-26474]

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OECA-2013-0316; FRL--10017-65-OMS]

Information Collection Request Submitted to OMB for Review and
Approval; Comment Request; NSPS for Onshore Natural Gas Processing
Plants (Renewal)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: The Environmental Protection Agency has submitted an
information collection request (ICR), NSPS for Onshore Natural Gas
Processing Plants (EPA ICR Number 1086.12, OMB Control Number 2060-
0120), to the Office of Management and Budget (OMB) for review and
approval in accordance with the Paperwork Reduction Act. This is a
proposed extension of the ICR, which is currently approved through
January 31, 2021. Public comments were previously requested, via the
Federal Register, on May 12, 2020 during a 60-day comment period. This
notice allows for an additional 30 days for public comments. A fuller
description of the ICR is given below, including its estimated burden
and cost to the public. An agency may neither conduct nor sponsor, and
a person is not required to respond to, a collection of information
unless it displays a currently valid OMB control number.

DATES: Additional comments may be submitted on or before December 31,
2020.

ADDRESSES: Submit your comments, referencing Docket ID Number EPA-HQ-
OECA-2013-0316, to: (1) EPA online using www.regulations.gov (our
preferred method), or by email to<EMAIL_ADDRESS>or by mail to:
EPA Docket Center, Environmental Protection Agency, Mail Code 28221T,
1200 Pennsylvania Ave. NW, Washington, DC 20460; and (2) OMB via email
to<EMAIL_ADDRESS>Address comments to OMB Desk Officer
for EPA.
    EPA's policy is that all comments received will be included in the
public docket without change including any personal information
provided, unless the comment includes profanity, threats, information
claimed to be Confidential Business Information (CBI), or other
information whose disclosure is restricted by statute.

FOR FURTHER INFORMATION CONTACT: Patrick Yellin, Monitoring,
Assistance, and Media Programs Division, Office of Compliance, Mail
Code 2227A, Environmental Protection Agency, 1200 Pennsylvania Ave. NW,
Washington, DC 20460; telephone number:<PHONE_NUMBER>; fax number:
(202) 564-0050; email address<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: Supporting documents, which explain in
detail the information that the EPA will be collecting, are available
in the public docket for this ICR. The docket can be viewed online at
www.regulations.gov, or in person at the EPA Docket Center, WJC West,
Room 3334, 1301 Constitution Ave. NW, Washington, DC. The telephone
number for the Docket Center is<PHONE_NUMBER>. For additional
information about EPA's

public docket, visit: http://www.epa.gov/dockets.
    Abstract: Owners and operators of affected onshore natural gas
processing plants are required to comply with reporting and record
keeping requirements for the General Provisions (40 CFR part 60,
subpart A), as well as for the specific requirements at 40 CFR part 60,
subparts KKK and LLL. Owners or operators of the affected facilities
must submit a one-time-only report of any physical or operational
changes, initial performance tests, and periodic reports and results.
Owners or operators are also required to maintain records of the
occurrence and duration of any startup, shutdown, or malfunction in the
operation of an affected facility, or any period during which the
monitoring system is inoperative. These reports are used by EPA to
determine compliance with these same standards.
    Form Numbers: None.
    Respondents/affected entities: Owners and operators of onshore
natural gas processing plants that that commenced construction,
reconstruction, or modification after January 20, 1984, and on or
before August 23, 2011.
    Respondent's obligation to respond: Mandatory (40 CFR part 60,
subpart KKK and 40 CFR part 60, subpart LLL).
    Estimated number of respondents: 362 (total).
    Frequency of response: Semiannually.
    Total estimated burden: 67,500 hours per year. Burden is defined at
5 CFR 1320.3(b).
    Total estimated cost: Total labor costs are $7,990,000 (per year),
which includes $68,400 in annualized capital/startup and/or operation &
maintenance costs.
    Changes in the Estimates: There is an adjustment decrease in the
total estimated burden as currently identified in the OMB Inventory of
Approved Burdens. This increase is not due to any program changes. The
change in the burden and cost estimates occurred because the number of
respondents subject to these requirements has decreased as those
respondents modify their sources and become subject to another NSPS
standard. As sources subject to NSPS Subparts KKK and LLL modify, they
become subject to NSPS Subpart OOOOa and cease being subject to NSPS
Subparts KKK and LLL. There is also a decrease in the estimated number
of respondents subject to NSPS Subpart LLL. This is due to a re-
examination of the Agency's ECHO database of sources subject to Subpart
LLL with a NAICS code of 211130 (natural gas extraction) and reporting
SO2 emissions.

Courtney Kerwin,
Director, Regulatory Support Division.
[FR Doc. 2020-26474 Filed 11-30-20; 8:45 am]
BILLING CODE 6560-50-P


[Federal Register Volume 87, Number 153 (Wednesday, August 10, 2022)]
[Notices]
[Page 48744]
[FR Doc No: 2022-17118]

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SECURITIES AND EXCHANGE COMMISSION

[Investment Company Act Release No. 34664; File No. 812-15350]

Runway Growth Finance Corp., et al.

August 4, 2022.
AGENCY: Securities and Exchange Commission (``Commission'' or ``SEC'').

ACTION: Notice.

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    Notice of application for an order (``Order'') under sections 17(d)
and 57(i) of the Investment Company Act of 1940 (the ``Act'') and rule
17d-1 under the Act to permit certain joint transactions otherwise
prohibited by sections 17(d) and 57(a)(4) of the Act and rule 17d-1
under the Act.

SUMMARY OF APPLICATION: Applicants request an order to amend a previous
order granted by the Commission that permits certain business
development companies (``BDCs'') and closed-end management investment
companies to co-invest in portfolio companies with each other and with
certain affiliated investment entities.

APPLICANTS: Runway Growth Finance Corp., Runway Growth Finance L.P.,
Runway Growth Capital LLC, RWAY IP Holdings LLC and Runway Growth
Finance Opportunities Fund I LP.

FILING DATES: The application was filed on June 15, 2022 and amended on
July 29, 2022.

HEARING OR NOTIFICATION OF HEARING: An order granting the requested
relief will be issued unless the Commission orders a hearing.
Interested persons may request a hearing on any application by emailing
the SEC's Secretary at [email protected] and serving the
Applicants with a copy of the request by email, if an email address is
listed for the relevant Applicant below, or personally or by mail, if a
physical address is listed for the relevant Applicant below. Hearing
requests should be received by the Commission by 5:30 p.m. on August
29, 2022, and should be accompanied by proof of service on applicants,
in the form of an affidavit or, for lawyers, a certificate of service.
Pursuant to rule 0-5 under the Act, hearing requests should state the
nature of the writer's interest, any facts bearing upon the
desirability of a hearing on the matter, the reason for the request,
and the issues contested. Persons who wish to be notified of a hearing
may request notification by emailing the Commission's Secretary at
[email protected].

ADDRESSES: The Commission: [email protected]. Applicants:
Thomas B. Raterman at [email protected]. Steven B. Boehm, Esq. and
Anne G. Oberndorf, Esq., Eversheds Sutherland (US) LLP, at
[email protected].

FOR FURTHER INFORMATION CONTACT: Bruce R. MacNeil, Senior Counsel, or
Kaitlin C. Bottock, Branch Chief, at<PHONE_NUMBER> (Division of
Investment Management, Chief Counsel's Office).

SUPPLEMENTARY INFORMATION: For Applicants' representations, legal
analysis, and conditions, please refer to Applicants' first amended and
restated application, dated July 29, 2022, which may be obtained via
the Commission's website by searching for the file number at the top of
this document, or for an Applicant using the Company name search field,
on the SEC's EDGAR system. The SEC's EDGAR system may be searched at,
at http://www.sec.gov/edgar/searchedgar/legacy/companysearch.html. You
may also call the SEC's Public Reference Room at<PHONE_NUMBER>.

    For the Commission, by the Division of Investment Management,
under delegated authority.
J. Matthew DeLesDernier,
Deputy Secretary.
[FR Doc. 2022-17118 Filed 8-9-22; 8:45 am]
BILLING CODE 8011-01-P


[Federal Register: May 24, 2006 (Volume 71, Number 100)]
[Notices]
[Page 29934]
[DOCID:fr24my06-64]

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DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Docket No. RP04-523-011]

Southern Natural Gas Company; Notice of Refund Report

May 16, 2006.
    Take notice that on May 1, 2006, Southern Natural Gas Company
(Southern) tendered for filing a refund report in compliance with the
Commission's letter order dated April 20, 2006.
    Any person desiring to protest this filing must file in accordance
with Rule 211 of the Commission's Rules of Practice and Procedure (18
CFR 385.211). Protests to this filing will be considered by the
Commission in determining the appropriate action to be taken, but will
not serve to make protestants parties to the proceeding. Such protests
must be filed on or before the date as indicated below. Anyone filing a
protest must serve a copy of that document on all the parties to the
proceeding.
    The Commission encourages electronic submission of protests in lieu
of paper using the ``eFiling'' link at http://www.ferc.gov. Persons

unable to file electronically should submit an original and 14 copies
of the protest to the Federal Energy Regulatory Commission, 888 First
Street, NE., Washington, DC 20426.
    This filing is accessible on-line at http://www.ferc.gov, using the

``eLibrary'' link and is available for review in the Commission's
Public Reference Room in Washington, DC. There is an ``eSubscription''
link on the Web site that enables subscribers to receive e-mail
notification when a document is added to a subscribed docket(s). For
assistance with any FERC Online service, please e-mail
<EMAIL_ADDRESS>or call<PHONE_NUMBER> (toll free). For

TTY, call<PHONE_NUMBER>.
    Comment Date: 5 p.m. Eastern Time on May 23, 2006.

Magalie R. Salas,
Secretary.
[FR Doc. E6-7890 Filed 5-23-06; 8:45 am]

BILLING CODE 6717-01-P