What chemicals are endocrine disruptors in birds?
Actually, very few have been tested in birds. DDT, its metabolite DDE and other organochlorine pesticides and some forms of PCBs show endocrine effects and effects on hormonally controlled traits in birds. Many studies have shown altered hormone concentrations that accompany impaired reproduction (when exposed to petroleum crude oil or parathion for example) but often these studies cannot say if altered hormone levels result from the exposure directly or because reproduction is impaired in other ways. More recent studies in fish and mammals have found hormone level effects resulting from exposure to vinclozolin and other fungicides, or pthalate esters, an industrial chemical. How is the exposure to, or effects of, endocrine disruptors measured? This is an area of great interest for the research community right now. For the action of sex steroids on development of reproductive function, the best way to demonstrate a functional effect is to expose breeding birds and then test the breedin
