Publication Year



endocrine system, fertility, estrogen, embryonic development, biology, xenopus laevis


Biology | Cell and Developmental Biology | Endocrinology | Physiology


Over the past forty years observations have been made that suggest something is going wrong in the environment. Decreased fertility and hatching success have been observed in birds, fish, and mammals; demasculinization and feminization have been seen in male fish and birds, and defeminization and masculinization have been seen in female fish and gastropods; and there may have been a decrease in the male sperm count in humans. These abnormalities point to a disruption of the endocrine system. The endocrine system elaborately coordinates the secretion of hormones in the body. It is hypothesized that many of the pollutants present in the environment mimic the hormone estrogen. When animals are exposed to these pollutants during development, development is disrupted and deleterious health effects occur.