pesticides as endocrine disruptors

Several synthetic chemicals used as pesticides have the capacity to interfere with hormone action in the mammalian body. These chemicals are known as endocrine disruptors. Exposure to endocrine disruptors before birth can change the development of sexual organs, neuroendocrine system and behaviour. We are studying whether long term exposure to low doses of organophosphorus insecticide Chlormephos and herbicide Atrazine affects development and function of reproductive tract and brain. In Chlormephos study, adult male and female mice were exposed to 3,5 |jg/ml and 0,35 jg/ml of Chlormephos in the drinking water. No statistically significant differences between treated and control groups were found in any of the observed parameters that included several indicators of testis development and blood levels of reproductive hormones, suggesting that Chlormephos does not act as an endocrine disruptor in reproductive tract. Elevated plus maze test revealed increased anxiety like behaviour in mice exposed neonatally to higher dose of Chlormephos. Microarray analyses revealed some differences in expression of genes that might be involved in the anxiety-like behaviour but we could not confirm several of them using quantitative RT PCR. On the other hand, studies with Atrazine did reveal some endocrine effects of prenatal and neonatal exposure to Atrazine, although these studies are still on-going and the results are not conclusive, yet.