Phthalates found in plastics could block hormone involved in sexual, cognitive function. Men, women and children exposed to high levels of phthalates – endocrine–disrupting chemicals found in plastics and some personal care products – tended to have reduced levels of testosterone in their blood compared to those with lower chemical exposure, according to a new study published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).