Environmental contaminants considered endocrine disruptors have been shown to affect testis development and function but the mechanisms of action are not clear. We now have analyzed the effects on the transcriptome in testes of mice exposed to mono-(2-ethylhexyl)-phthalate (9.2; 46.3 or 92.7 mg/kg/d), zearalenone (1.3; 3.9 or 6.6 mg/kg/d), lindane (16.6; 32.2 or 64.4 mg/kg/d), bisphenol-A (0.16; 16 or 64 mg/kg/d) or 17β-estradiol (0.006; 0.012 or 0.048 mg/kg/d). The compounds were orally administered in the drinking water during distinct developmental periods: (A) mothers were exposed only during the two weeks before mating; (B) the exposure was continued during pregnancy until birth or (C) exposure was continued for a further four weeks after birth. Testes were studied at four weeks of age. Mono-(2-ethylhexyl)-phthalate and zearalenone, both produced specific alterations of gene signatures. Interestingly, this was irrespective of the concentration of the toxicant or the developmental period during which exposure occurred.