A controversial study claims to have found a link between wearing make-up during pregnancy and lower IQ scores in children. Exposure to the highest levels of two phthalate chemicals led to a lowering of IQ scores at age seven by more than six points, US scientists found. The scientists claim the link remained after taking account of known factors that can influence child IQ, such as the mother’s intelligence and the quality of the home environment.
Phthalates are man-made chemicals thought to interfere with the natural hormones that are crucial to overall health. They are found in everything from PVC flooring and shower curtains to car dashboards – and may also be in our food. Tiny particles can enter our systems either through breathing or eating.
Researchers in the New York investigated four phthalates and demonstrated an association with two, known as DnBP and DiBP. Both are found in a wide range of consumer products including dryer sheets, vinyl fabrics, lipstick, hairspray, nail polish and some soaps. The magnitude of these IQ differences is troubling,’ said Professor Robin Whyatt, from Columbia University’s Mailman School of Public Health, who took part in the study.
‘A six or seven-point decline in IQ may have substantial consequences for academic achievement and occupational potential.’ The scientists assessed the pthalate exposure of 328 New York City women and their children, all of whom were from low-income communities. Break down chemicals from the compounds left after they had been processed in the body were measured in urine samples during the last three months of pregnancy.
Children of mothers whose exposure to DnBP and DiBP was in the top 25 per cent had IQ scores 6.6 and 7.6 points lower, respectively, than those of mothers exposed to the lowest concentrations. Associations were also seen for specific aspects of IQ, such as perceptual reasoning, working memory and processing speed.