UNITED ST A TES ENVIRONMENT AL PROTECTION AGENCY 

WASHING TON, D.C. 20460 

MEMORANDUM 

Date: March 4, 2015 

OFFICE OF 

CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

SUBJECT: Momfluorothrin: Response to Registrant Comments from Sumitomo Chemical 

on the Human Health Risk Assessment (December 9, 2014; DP Barcode: 

D409621). 

PC Code: 016331 

Decision No.: 474816 

Petition No.: NA 

DP Barcode: D425171 

Registration No.: NA 

Risk Assessment Type: NA 

TXRNo.:NA 

Regulatory Action: Section 3 Registration 

Case No.: None 

CAS No.: NA 

MRID No.: NA 40 CFR: New Active Ingredient 

FROM: Monica Hawkins, Ph.D., M.P.H., Risk Ass 

Christopher Schlosser, Toxicologist 

Risk Assessment Branch VI 

THROUGH: Donna Davis, Acting Branch Chief 

Risk Assessment Branch VI 

Health Effects Division 

TO: Julie Chao, Risk Management Team 1 

Kahle Davis, Risk Management Team 25 

Marietta Echeverria, Chief 

Insecticide Rodenticide Branch 

Registration Division (7505P) 

ental Health Scientist ~ 

HED has received comments on the review of the human health risk assessment for Section 3 

Registration December 9, 2014; DP Barcode: D409621. 

EP A's Response: 

HED acknowledges the submitted corrections from Sumitomo Chemical. Since the requested 

revisions do not impact the risk calculations or conclusions from the December 9, 2014 risk 

assessment, no revision to the momfluorothrin risk assessment was undertaken at this time. 

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However, HED will incorporate the recommended changes into the next momfluorothrin risk 

assessment. 

Sumitomo's Comments: 

(1) 870.3100 90-day Oral Toxicity-Rat 

870.3150 90-day Oral Toxicity-Dog 

870.3700a Prenatal Developmental Toxicity Study - Rat 

870.4100 Chronic Toxicity-Rat 

870.4300a Carcinogenicity-Rat (Typo; see comment No. 10) 

870.4300b Carcinogenicity-Mouse 

870.6200 Acute Neurotoxicity Screening Battery -Rat 

870.6200 Subchronic Neurotoxicity Screening Battery -Rat 

870. 7800 Immunotoxicity-Rat 

The descriptions of "lack of stability data" in the last paragraph were incorrect. 

In these studies, stability of test substance was confirmed based on the data of expiry date. 

(2) P13. Comment 1st paragraph L3 

In addition to tremor, salivation but not impaired gait and muscular rigidity was observed in the 

acute neurotoxicity study. 

(3) P38-43. Typo Table A2.2 S-15632 => S-1563 

(4) P40. Typo Table A.2.2. Carcinogenicity (rat), Guideline No. : 870.4300 => 870. 4200 

(5) P40. Typo Table A.2.2. Carcinogenicity (rat), F:O, ... ,or 188 => F:O, ... ,or 182 

(6) P42. Typo 4th paragraph Ll, almost entirely=> at almost constant rate 

(7) P42. Typo 5th paragraph L6, 3.4893% => 3.483% 

(8) P46. Typo 870.3200 28-day dermal toxicity 1st paragraph L3, 

5days/week during a 28-day period=> 7days/week during a 28-day period 

(9) P49. Comment 6th paragraph L3 

However, delayed sexual maturation in females is considered treatment related as the effect was 

... =>However, delayed sexual maturation in females is considered treatment related although 

this was attribute to the retarded growth of the pups. As the effect was ... 

(10) P51. Typo A.4.5 Carcinogenicity, 870.4300a Combined Chronic 

Toxicity/Carcinogenicity -Rat=> 870.4200a Carcinogenicity -Rat 

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(11) P5 l. Comment Last paragraph L4, only reaching statistical significance in males. => not 

only males but also females. 

(12) P52. Typo Carcinogenicity-Mouse 1st paragraph L3, 673 => 639, 433 => 427, 934 ==> 

853 

(13) P55. Typo 4th paragraph Ll, absorption=> plasma 14C concentration 

(14) P55. Typo Last paragraph L2, parent compound=> 14C 

(15) P55. Typo Last paragraph L3, in male rats=> in both male and female rats 

(16) P56. Typo 6th paragraph L4, n=3 => n=4 

(17) P56. Typo with comment 7th paragraph L6, 3.5% => 3%, The value should be rounded to 

3% in accordance with the OECD guidance notes on dermal absorption to avoid a false 

impression of accuracy. 

(18) P58. Typo A.4.10 Mode of Action 3rd paragraph L4 and 8, CYP2Bl0 activity=> 

expression of CYP2B I 0 

(19) P59. Typo 2nd paragraph L2, ... in the rat=> in the mouse 

(20) P59. Typo 4th paragraph L3, ... in all rats=> in all mice 

(21) P59. Typo 4th paragraph LIO, ... for CYP2 =>for CYP2B 

(22) P60. Typo 3rd paragraph Ll3, Study Days 11-15 =>Study Days 8-11 and 11-15 

(23) P60. Typo 3rd paragraph LI 9, gene expression=> delete please (not examined in this 

study) 

(24) P60. Typo 3rd paragraph L22-24, ... a marked and significant ... CYP2A10. =>delete 

please (not examined in this study) 

(25) P60. Typo 4th paragraph L3, (2.8- => (2.9-

(26) P61. Typo 1st paragraph L 1, for 14 days => for 7 days 

(27) P61. Typo 4th paragraph L8 and 11, CYP2Bl/2 activity=> expression of CYP2Bl/2 

(28) P62. Typo 4th paragraph L8, 300 ppm=> 3000 ppm 

(29) P62. Comment 4th paragraph L9, in all groups=> not conducted animals in recovery 

group 

(30) P63. Typo 4th paragraph L7, UGP-glucuronosyltransferase =>UDPglucuronosyltransferase 

(31) P64. Typo 2nd paragraph L7, MRIDs .. .490200602 => 49020062 

(32) P64. Typo 3rd paragraph L8, CYP2B expression=> CYP2B (expression is not 

necessary) 

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(33) P64. Typo 4th paragraph L7, 2-8 fold=> 2.8-fold 

(34) · P64. Typo 4th paragraph L8, CYP2B expression=> CYP2B activity 

(35) P64. Typo 5th paragraph L3, diffused=> centrilobular 

(36) P65. Typo 3rd paragraph L4, 30000 ppm=> 3000 ppm 

(37) P66. Comment 2nd paragraph L3, 

Enlarged livers, diffuse hepatocellular hypertrophy and thyroid follicular cell hypertrophy were 

observed in 7/10 animals dosed with 10,000 ppm for 7 or 14 days.=> It is imprecise. Enlarged 

livers, diffuse hepatocellular hypertrophy and thyroid follicular cell hypertrophy were observed 

in 10 or 8/10, 10/10, and 7/10 animals dosed with 10,000 ppm for 7 or 14 days, respectively. 

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