Researchers from the University of Granada and ibs.GRANADA link higher prenatal exposure to a mixture of plastic-related chemicals with lower IQ scores at age three. The reported difference averages three points per unit increase in the mixture.
Women in the French SEPAGES cohort provided as many as 42 urine samples during pregnancy, allowing researchers to track chemicals that can leave the body quickly. In an analysis of 380 mother-child pairs, the team assessed exposure through urinary measurements of 26 phthalate metabolites and phenols. Higher exposure to a mixture of plastic-related contaminants during the third trimester was linked to lower IQ scores at age three, measured with a standardized test.
The difference was approximately 2.86 IQ points for each unit increase in the mixture’s concentration, rounded to three points in the study’s summary. Researchers identified six priority chemicals in the mixture: bisphenols A and S, plus the phthalates DEHP, DEP, DnBP and DiBP. Four substances also showed statistical associations in individual analyses. The mixture result reflects combined exposure. It does not mean every child experienced the same change in IQ.
Researchers from the University of Granada (UGR) and the Granada Biosanitary Research Institute (ibs.GRANADA) conducted the work with France’s National Institute of Health and Medical Research (INSERM). Their findings appeared in Environmental Health Perspectives in 2026. The analysis drew on mothers and children in SEPAGES, a population-based French cohort established between 2014 and 2018 with funding from the European Research Council (ERC).
Urine samples were tested for endocrine disruptors such as bisphenol A (BPA) and phthalates. These substances are used in some food packaging and cans, as well as plastics and cosmetics. BPA is used in polycarbonate plastics and epoxy resins, including some can coatings. Food is a major route of exposure when BPA migrates from packaging into what people eat. Researchers accounted for the mothers’ age and weight, then adjusted for socioeconomic status. Maternal intelligence and lifestyle habits were also included in the analysis.
The result shows an association, not proof that the chemicals caused lower scores in individual children. To improve the exposure assessment, the team collected repeated samples rather than relying on one or a few collections in each trimester, as earlier studies had done. That matters because phthalates and bisphenols, along with their metabolites, can leave the body quickly. Claire Philippat of INSERM said repeated measurements provide a more precise assessment of exposure over time, a standard required by regulators such as the European Food Safety Authority (EFSA). EFSA evaluates chemicals that migrate from food-contact materials into food and drink using migration and toxicological data.
The researchers also reviewed toxicological and epidemiological evidence in a structured analysis. Their statistical models incorporated findings from previous international studies instead of relying solely on SEPAGES data. Ainhoa Pérez Cantero, a doctoral researcher at UGR, ibs.GRANADA and Hospital Universitario Clínico San Cecilio de Granada, said this broader evidence base supports the reported association.
The researchers say the findings matter beyond France. Vicente Mustieles, the study’s lead author and a Miguel Servet researcher at ibs.GRANADA, UGR and Hospital Universitario Clínico San Cecilio de Granada, said more than 90% of people in both France and Spain have measurable levels of these compounds in their urine. Spanish research from the multicentre birth cohort Infancia y Medioambiente (INMA) has also linked prenatal and childhood exposure to the same chemicals with neurodevelopmental changes.
The team recommends reducing exposure by limiting ultra-processed foods and keeping plastic containers or utensils away from food. Its advice is to choose glass or stainless steel and use fewer cosmetics. Where possible, seek products without fragrances or endocrine disruptors. EFSA also has guidance on data requirements for assessing the safety of bisphenols other than BPA and their derivatives, covering alternatives as well as BPA itself.
