Phthalates –– chemicals used to soften plastics, including plastic water bottles –– can disrupt human endocrine function. The endocrine glands produce and regulate hormones that manage our vital functions, such as reproduction, breathing, and thinking. Disrupting these bodily processes can lead to birth defects, cancer, or developmental problems in babies and children.¹⁰

Researchers, public health officials, policymakers, plastics industry representatives, and citizen organizations have long been debating whether and how much phthalates and other synthetic chemicals harm human health. Scientists have confirmed that phthalates can disrupt the endocrine system in rodents and are “ubiquitous in our world –– in plastics, nail polish, perfumes, toothbrushes, pesticides, paint, and the coating on time–release pills.” But, ethical issues aside, proving this in humans is more difficult. For example, when studying chemical exposure in the womb (or before birth), “determining the effect of any particular chemical on an individual is nearly impossible because it is so difficult to figure out which chemicals the individual’s mother was exposed to during pregnancy.” However, a researcher at the University of Rochester School of Medicine published the first study to link women’s prenatal phthalate exposure to measurable effects on the genital development of their male offspring. She favors further study “because the mothers of babies with the physical traits she observed had been exposed to levels of phthalates that, according to estimates from the Centers for Disease Control and Prevention, are present in the bodies of one–quarter of all American women.” ¹⁰

For footnotes, see our report, Take Back the Tap.