The study, published in Environmental Health Perspectives [1], found that “exposure to a mixture of chemicals, some of which are endocrine disruptors, during sensitive periods, particularly pregnancy, is likely to affect children’s neurodevelopment,” explained lead author Claire Philippat, a researcher at INSERM and the University of Grenoble, in comments to AFP.
The research was conducted by an INSERM team at Grenoble Alpes University, in collaboration with the CNRS, Grenoble University Hospital, and the University of Granada in Spain. It draws on data from 380 mothers and their children enrolled in the Sepages cohort, combined with a model incorporating existing knowledge in this field.
Phthalates and bisphenols
The researchers assessed exposure to four phthalates (DEHP, DEP, DnBP and DiBP) and two bisphenols (A and S) using repeated urine samples collected from pregnant women and their babies — an approach that differs from many previous studies, which relied on a single sample.
They found associations between maternal exposure to these substances during pregnancy and children’s IQ scores at age three, measured using a standardized test.
“On average, IQ scores decreased by 2.86 points when exposure to all the substances in the mixture increased by one level,” said Rémy Slama, INSERM research director and a member of the research team, in a press release.
However, Philippat stressed that “this does not mean that every exposed child lost three IQ points, but rather that the average IQ score across the French population would be three points lower.”
“A loss of a few IQ points may seem insignificant for an individual child, but at the population level, it means more children experiencing difficulties, with consequences for schools, healthcare and the economy,” added Philippat.
Everyday chemicals
According to Philippat, these phthalates and bisphenols are “detected in almost the entire population.” They are ubiquitous in the environment and are used as additives in certain plastics, including PVC, found in flooring, shower curtains and some pipes. They can also be present in perfumes, cosmetics, varnishes and paints. Bisphenols are additionally used as ink developers in thermal paper, including cash register receipts, she explains. [2]
Reducing the use of certain cosmetics and limiting contact with food packaged in plastic, particularly when food is heated, can help reduce exposure. However, the researcher concludes that only “the regulation and restriction of substances proven to be harmful” can provide effective protection for the population.
A previous INSERM study found that reducing exposure to certain everyday products, including cosmetics, could rapidly and significantly lower urinary concentrations of certain chemical pollutants and endocrine disruptors, such as bisphenol A.
