Researchers found health impacts at exposure levels that are 8,000 times lower than some regulatory limits.
“Safe” limits on human exposure to phthalates set by national and international regulatory authorities may not adequately protect public health, according to a new analysis published in the journal Environmental Health on Monday.
The study, synthesizing dozens of human studies, drew significant associations between phthalate exposure and human reproductive, neurodevelopmental, behavioral, hormonal, and metabolic health problems. It also underpins the need for reassessing regulatory standards with up-to-date science.
A group of chemicals widely used in the plastic industry to soften plastic products, phthalates are omnipresent in modern life. From rubber duckies to garden hoses to fast food burgers, phthalates can easily sneak into our bodies and disrupt our endocrine system by heisting hormone receptors—such as the estrogen receptors or the retinoic acid X receptors—and messing with gene expression switches. Human and animal studies have linked phthalates to a wide range of health impacts, including birth and reproduction problems, impaired brain development, diabetes, and cancer.
“We know that the exposure [to phthalates] is quite broad,” Maricel Maffini, an independent public health consultant based in the U.S. and the lead author of the paper, told EHN. “We were trying to figure out whether the doses that regulators considered safe for people to be exposed to are still protective.” The study was funded by Swiss conservation nonprofit, MAVA Foundation, and Food Packaging Forum, a Zurich-based science communication nonprofit focused on food packaging materials and their impacts on health.
This paper focused on five what Maffini called “worst-offender” phthalates: benzyl butyl phthalate (BBP), diisobutyl phthalate (DIBP), dibutyl phthalate (DBP), dicyclohexyl phthalate (DCHP), and bis(2-ethylhexyl) phthalate (DEHP).
To investigate the health impacts, the authors extracted data from 38 previously published papers where any of the five chemicals or their metabolites were shown to have a statistically significant association with a health outcome. They then extrapolated the level for each phthalate linked to the adverse health effects and compared them with phthalates’ safe limits set by the European Chemicals Agency, which proposes phthalate regulations to the European Commission, and the U.S. Consumer Protection Safety Commission, whose phthalate ban in the U.S. has only been limited to children’s toy or child care articles.
Environmental Health News, 17 November 2021