Pregnant? Pesticides Affect Your Child’s IQ

Reported April 25, 2011

(Ivanhoe Newswire) -- Moms-to-be who consume certain foods sprayed with pesticides may put their child at risk for having a lower IQ. Researchers at the University of California, Berkeley's School of Public Health found that prenatal exposure to organophosphate pesticides (used widely on food crops) is linked to lower intelligence scores at age 7.

Organophosphates (OP) are a class of pesticides that are well-known neurotoxicants. Chlorpyrifos and diazinon, two commonly used OP pesticides, have been phased out over the past decade, mainly due to the health risks they impose on children.
Researchers discovered that as OP levels increased in mothers during their pregnancy, IQ scores dropped in their children. Children with the highest levels of prenatal pesticide exposure scored seven points lower on IQ tests when compared to children who had the lowest levels of exposure.

Brenda Eskenazi, UC Berkeley professor of epidemiology and of maternal and child health, is quoted as saying: "That difference could mean, on average, more kids being shifted into the lower end of the spectrum of learning, and more kids needing special services in school."

Researchers at UC Berkeley, Mt. Sinai Medical Center, and Columbia University examined the children living in their respective locations; UC Berkeley focused on children in an agricultural center known as Salinas, and Columbia University looked at children in the urban environment of New York City.

An ongoing longitudinal study led by Eskenazi and her team of researchers began enrolling pregnant women in the study in 1999. Researchers at UC Berkeley and Mt. Sinai measured pesticide metabolites in the mother’s urine, and researchers at Columbia looked at umbilical cord blood for specific pesticides.

During pregnancy and after the children were born, study participants came to regular visits where staff at the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) asked them questions, and measured their children’s health and development.

The Wechsler Intelligence Scale for Children -- Fourth Edition (WISC-IV) was used to measure the mental development of the children at age 7. The test measured the children’s verbal comprehension, perceptual reasoning, working memory and processing speed. Each of the four subcategories saw significant decreases in scores associated with higher levels of pesticides when the mothers were pregnant, and these results remained consistent even after researchers considered maternal education, family income and exposure to other environmental contaminants.

Although the results of the study showed a significant correlation between childhood IQ and exposure to pesticides, any further exposure to OPs after birth did not impact IQ; this fact alone stresses the importance of fetal development.

The researchers strongly suggest consumers to reduce the use of pesticides in their homes, and to use bait stations instead of sprays if pesticide are needed. They also said that consumers should thoroughly wash fruits and vegetables and consider using a soft brush to scrub off residue left behind. Also, eating organic foods is an excellent way to avoid pesticide exposure.

Eskenazi is quoted as saying: "I'm concerned about people not eating right based on the results of this study. Most people already are not getting enough fruits and vegetables in their diet, which is linked to serious health problems in the United States. People, especially those who are pregnant, need to eat a diet rich in fruits and vegetables."


SOURCE: Environmental Health Perspectives, published online April 21, 2011