Abstract
Parabens are most wildly used in food, cosmetics and pharmaceutic products as preservatives caused of safety and cheap. we had examined that paraben had estrogenic activity through the in vivo and in vitro experiments in last year. We demonstrated that most of parabens(ethyl, butyl, propyl, isobutyl, isopropyl) increased significantly uterus weight as well as induced proliferation of MCF-7 cell and binding of estrogen receptor as endocrine disrupter compounds. In this study, we evaluated that whether parabens have effect on male reproductive system or not. the male rats were administrated parabens by oral injection then examined separation of preputial day for $PND23\simPND52$. As the results, most parabens delayed pubertal development compare to control group. The separation of preputial day of Butyl and Propyl parabens at high concentration were PND 44 days and PND 45days compared to control group as PND 40 days. Even though, parabens as endocrine disrupter wildly spread in food, cosmetics and pharmaceutic products, we didn't have the safe guideline. In abroad, they are re-evaluating safety assessment for parabens. In conclusion, parabens delayed pubertal development in juvenile parabens are consider as endocrine disrupter chemicals.