As if bringing another human being into this world wasn’t stressful enough, pregnant women are told to avoid many of life’s small pleasures: from eating sushi and hot dogs to petting cats and dying their hair.
While doctors have proven some of these prohibitions to be unnecessary, a new study shows that there are items many women use on a day-to-day basis that can affect their offspring.
Researchers at Columbia University’s Mailman School of Public Health say in the paper, published in the scientific journal PLOS one, that exposing a fetus in the late stages of pregnancy to the chemicals used to produce such common products as lipstick, hairspray, nail polish, dryer sheets, shower curtains, and some soaps can lower the child’s IQ by up to 7.6 points.
The chemicals, two phthalates—DnBP and DiBP—have already been banned in children’s toys in the United States. They can make their way into mothers’ bloodstreams when they eat or drink foods that have been in contact with containers and products containing them, or breathe in air that contains phthalate vapors or contaminated dust.
Using a sample of 328 mothers enrolled in prenatal care in New York City hospitals, and their children, the scientists measured the levels of the chemicals in the mothers’ urine in the third trimester of their pregnancies. The children took the IQ tests when they were 7 years old, and those whose mothers had a higher concentration of DnBP and DiBP in their system scored lower by 6.6 and 7.6 points, respectively.
Although the research does not prove that the chemicals were what caused the reduction in IQ, the scientists say the association is persistent. Other studies have shown that phthalates disrupt the actions of hormones, including testosterone and thyroid hormone. The researchers also did not determine how the chemicals were conveyed to the babies in utero, or what products the mothers had been exposed to.
The study’s senior author, Robin Whyatt, Professor of Environmental Health Sciences and deputy director of the Columbia Center for Children’s Environmental Health at the Mailman School told Science Daily that the magnitude of the IQ differences was “troubling.” He said that this sort of decline in IQ could have “substantial consequences for academic achievement and occupational potential.”
The researchers recommend that pregnant women stay away from scented products such as dryer sheets, and give up microwaving food in plastic containers. They also suggest avoiding altogether recyclable plastics designated with a 3, 6, or 7 in the US.
It all adds up to more reasons to use glass containers and reusable cotton bags. They’re not just better for your child, but also for the environment.