Possible reproductive toxicity of styrene in peripubertal male mice

Environmental estrogens (endocrine disruptive chemicals) have been shown to affect reproduction in wild life and it has been reported that maternal exposure to those chemicals has adverse effects on the male reproductive tract. However, little is known about the potential effects of prepubertal or pubertal exposure to environmental estrogens on the male reproductive tract. Here we examine plasma hormone levels of mice following 4-week oral administration of styrene. Plasma free testosterone levels were dramatically decreased following 4 weeks of styrene treatment compared with control group. No differences in plasma corticosterone and luteinizing hormone levels were seen between styrene and control groups. Thus, exposure to styrene around pubertal period may directly disrupt the male reproductive tract. These facts suggest that more detailed studies regarding assessment of the risk to the developing human testes from exposure to styrene and other environmental estrogens in prepubertal and pubertal period are warranted.