Potassium Dichromate Impact on some Biomarkers of Physiological Development (Vaginal Opening and Weight at Sexual Maturity) in Female Rats Related to Exposure Moment

The study was carried out on white Wistar female rats exposed to potassium dichromate (Cr VI) in different periods: in utero (28 female rats, derived from 20 exposed pregnant females, divided in four groups, one control - C and three experimental – E), in suckling and prepubertal period (in each stage, 28 offspring were divided in four groups: one C and three E). The levels of exposure were: E1 – 25 - LOAEL, E2 - 50 - 2XLOAEL, E3 - 75 -3XLOAEL ppm Cr VI in drinking water or through milk in suckling period. Exposure to Cr VI determined significant delay of vaginal opening (onset of puberty) in direct correlation with the exposure level and significant decrease of body weight in the moment of vaginal opening under the optimum weight and inversely correlated to exposure level. The most critical period of exposure for both biomarkers was in utero.