<6>A ~ Task Force 

Document Control Office 

Office of Pollution Prevention and Toxics 

Room 6428 

U.S. Environmental Protection Agency 

1200 Pennsylvania Ave., N.W. 

Washington, DC 20460 

P.O. Box 331, Millwood, VA 22646 (540) 837-1 602 

October 27, 2014 

Re: Testin& Consent Order for Ethylene Dichloride; 

Dear Sirs: 

Analysis of Data for Determination of Second Generation Study 

(Docket No. OPPT-2003-0010) 

. The extended one-generation drinking water reproductive toxicity study for ethylene dichloride in rats has 

reached the stage to decide whether there is a need to go further with a second generation analysis based on the 

triggers defined in the OECD guideline. We have already provided the available unaudited data to EPA to 

review which includes: behavior data, developmental landmarks and survival to weaning data, nipple/areola and 

anogenital distance data, balanopreputial separation, summary of organ weight data for males and females, 

individual organ weight data for males and females, most current body weight and body weight changes for 

males and females (F 1 ), necropsy findings for pups, the draft pathology report with FO pathology tables, 

historical control summary of reproductive performance, pup survival indices, pup body weights, pup organ 

weights, developmental landmarks, male and female organ weights, sperm concentration and morphology. 

We observed a noticeable difference between the experimental control (45.4+/-2.55) and high dose (47.1+/-

2.54) mean balanopreputial separation time. However, this was not statistically significant, it was less than two 

days, and when compared to mean historical controls (45.6 +/-1.59) the high dose value was closer to the 

historical mean value than the experimental dose value. Additionally, there appeared to be a trend in decrease 

body weight with dose which was not statistically significant. This was was likely attributed to decreases in 

water consumption due to possible palatability issues, as well as a decrease in food consumption, and not related 

to developmental toxicity. There was also a noticeable difference between mean anogenital distance in males 

(control 4.05+/-.467) and high dose ( 4.25+/-.164) and females (controls 2.11 +/-.239) and high dose 

(2.20+/-.148) which were not statistically significant. The high dose experimental means were also closer to 

historical control values (males 4.17+/-.374) (females 2.25+/-.210). 
There were no significant/relevant dose-related differences found with regard to the other toxicological data 

examined., Furthermore, balanopreputial separation is not assessed in the typical second generation because the 

pups are sacrificed before sexual maturation. 

Based on these data there are no meaningful dose-related effects and a second generation would not likely 

contribute to the assessment of the developmental toxicity of ethylene dichloride. If you have questions 

regarding our interpretation of the data, a teleconference should be scheduled immediately, since the cut-off date 

for initiating the second generation study is October 3181

• 

Sincerely, 

Peter E.Voytek, Manager HAP Task Force 

cc: Jim Lamb 

Jacque Maurisson 

Jeff Char lap 

John E. Schaeffer 

Jim Bus 

Caffey Norman, Esq