Endocrine disruptor include DDT, polychlorinated biphenyls (PCB's), bisphenol A (BPA), polybrominated diphenyl ethers (PBDE's), and a variety of phthalates. In fact, almost all plastic products, including those advertised as "BPA free", have been found to leach endocrine-disrupting chemicals. In a 2011, study it was found that some "BPA-free" products released more endocrine active chemicals than the BPA-containing products. Other forms of endocrine disruptors are phytoestrogens (plant hormones). Xenoestrogens are a type of xenohormone that imitates estrogen. Synthetic xenoestrogens include widely used industrial compounds, such as PCBs, BPA and phthalates, which have estrogenic effects on a living organism. Alkylphenols are xenoestrogens. The European
Endocrine disruptor BDE-47, affects the reproductive system and thyroid gland of female rats in doses of the order of those to which humans are exposed. Low concentrations of endocrine disruptors can also have synergistic effects in amphibians, but it is not clear that this is an effect mediated through the endocrine system. Critics have argued that data suggest that the amounts of chemicals in the environment are too low to cause an effect. A consensus statement by the Learning and Developmental Disabilities Initiative argued that "The very low-dose effects of endocrine disruptors cannot be predicted from high-dose studies, which contradicts the standard