The complexity of human biology makes it impossible to know for certain if endocrine disruption accounts for human penile deformities. Toxicologists point out that an overall assessment of risk must include other factors in addition to exposure including absorption, metabolism, excretion, bioaccumulation and other chemical interactions (Harrison et al., 1997). Many skeptics observe lack of analytic ability to document contaminant levels during critical windows of exposure (Safe, 2000). Further, the environmental estrogens studied (DDT, PCB and bis-phenol A) are quite weak compared to the well studied potent estrogen DES which did not cause penile deformities (Joffe, 2001). While environmental estrogens may be unlikely in contributing to penile deformities, the antiandrogens (phthalates, vinclozolin and DDE) are more plausible is this regard, as maleness is critically dependent upon androgen action. Observers note that, in general, the environmental concentrations of persistent organochlorine compounds have been decreasing over the past two decades. Some feel that our current levels of exposure are too low and the potency of the anti-androgens too weak to account for any significant developmental genital effect (Williams et al., 2001). Caution and restraint are always reasonable in matters of data intrepretation. Past researchers were reassured that pthtalate esters were quite safe when they first were assessed for possible harmful effects on male fertility. Unfortunately it took different models, analyzing transgenerational effects, before it became crystal clear that these compounds can dramatically affect male genital development following experimental maternal exposure at dosages and concentrations currently present in most women. We can not now be so reassured that our male development is unaffected by any of the over 65,000 manmade organochlorine compounds on the planet. Multiple observations from diverse disciplines provide credible evidence that proliferation of xenobiotic chemicals can cause potentially disastrous unintended consequences for the male gender, and upon reflection, our species.