Differing estrogenic activities for the enantiomers of o, p'-DDT in immature female rats.

Female rats (20-21 days) were given single intraperitoneal injections of (+/-)-o,p'-DDT, (--)-o,p'-DDT, or (+)-o,p'-DDT. At 18 h their uteri were excised and the estrogen sensitive parameters, uterine wet weight, and uterine glycogen content were measured. For o,p'-DDT, the levo enantiomer is the more active estrogen in immature female rats. Optical resolutions of other racemic environmental xenobiotics may be important in the evaluation of their biological effects.