Phthalates are chemicals used to make vinyl and other plastic materials soft and flexible. Phthalates are present in many different commonplace items, such as toys, food storage containers and wrappers, carpets, car interiors, and anything made of PVC.

Phthalates are classified by the EPA as a probable human carcinogen, meaning they most likely cause cancer at certain concentrations, and have been shown to damage the liver and testes of rodents. A few studies have shown that genital abnormalities in baby boys are connected to high concentrations of phthalates in their mothers’ urine. Abnormal male genital development is also connected to overexposure to phthalates during infancy. In 1999 the European Union imposed a ban on phthalates in toys for children under three, to prevent possible health problems. Many foods contain phthalates that leech from their plastic packaging, especially when food and plastic are heated together.