Ovarian toxicity of 4-phenylcyclohexene in female B6C3F1 mice

Abstract

4-Phenylcyclohexene (4PC), a contaminant released from latex adhesives used to produce carpet, is structurally similar to the ovarian toxicant, 4-vinylcyclohexene (VCH). VCH causes depletion of primary ovarian follicles in mice. Our aim was to determine if the related compound, 4PC, also causes ovarian damage. Groups of B6C3F1 mice were given either: sesame seed oil (vehicle control), 3 mmole/kg 4PC (4PC-3), 6 mmole/kg 4PC (4PC-6), or 6 mmole/kg VCH (positive control), ip, daily for 30 days. Vaginal smears were done daily to determine the stage of estrus. On day 31, the mice were killed and the ovaries were fixed and stained. The numbers of primary and secondary follicles were significantly reduced in the VCH treated mice, but not in 4PC treatment groups. The number of estrous cycles/30 days was significantly reduced in VCH and 4PC-6 treated groups. This study suggests that although the substitution of a phenyl group (4PC) for a vinyl substituant (VCH) on the cyclohexene ring appears to eliminate the follicular loss, monitoring of the estrous cycles may be an early indication of an adverse reproductive effect for 4PC.