Three independent studies published simultaneously in EHP reach similar conclusions

Newswise — (RESEARCH TRIANGLE PARK, NC) Three independent investigations published online April 21 ahead of print in the peer-reviewed journal Environmental Health Perspectives (EHP) have reached similar conclusions, associating prenatal exposure to organophosphate (OP) pesticides with IQ deficits in school-age children. The fact that three research groups reached such similar conclusions independently adds considerable support to the validity of the findings.

The three studies were conducted at the University of California, Berkeley, School of Public Health; the Mailman School of Public Health at Columbia University; and Mount Sinai School of Medicine. All three involved cohorts of women enrolled during pregnancy. The Berkeley and Mount Sinai investigators measured OP pesticide metabolites in the pregnant women’s urine, while the Columbia investigators measured the OP pesticide chlorpyrifos in umbilical cord blood. Intelligence tests were administered to children of these mothers between ages 6 and 9 years at Mount Sinai and at age 7 years at Berkeley and Columbia.

Although the study findings are not directly comparable, all three investigations found evidence linking prenatal OP pesticide exposures with adverse effects on cognitive function that continued into early childhood. “It is well known that findings from individual epidemiologic studies may be influenced by chance and other sources of error. This is why researchers often recommend their results be interpreted with caution until they are supported by similar findings in other study populations,” said EHP Editor-in-Chief Hugh A. Tilson. “As a group, these papers add substantial weight to the evidence linking OP pesticides with adverse effects on cognitive development by simultaneously reporting consistent findings for three different groups of children.”

Each investigation was funded in part by the National Institute of Environmental Health Sciences and U.S. Environmental Protection Agency as part of the Children's Environmental Health and Disease Prevention Research Centers program. Additional funding came from other government and private sources.

The three articles will be available online April 21, free of charge.

“Prenatal Exposure to Organophosphates, Paraoxonase 1, and Cognitive Development in Childhood” will be available at http://ehponline.org/article/info:doi/10.1289/ehp.1003183. Study coauthors include Stephanie M. Engel, James Wetmur, Jia Chen, Chenbo Zhu, Dana Boyd Barr, Richard L. Canfield, and Mary S. Wolff.

“Prenatal Exposure to Organophosphate Pesticides and IQ in 7-Year-Old Children” will be available at http://ehponline.org/article/info:doi/10.1289/ehp.1003185. Study coauthors include Maryse F. Bouchard, Jonathan Chevrier, Kim G. Harley, Katherine Kogut, Michelle Vedar, Norma Calderon, Celina Trujillo, Caroline Johnson, Asa Bradman, Dana Boyd Barr, and Brenda Eskenazi.

“7-Year Neurodevelopmental Scores and Prenatal Exposure to Chlorpyrifos, a Common Agricultural Pesticide” will be available at http://ehponline.org/article/info:doi/10.1289/ehp.1003160. Study coauthors include Virginia Rauh, Srikesh Arunajadai, Megan Horton, Frederica Perera, Lori Hoepner, Dana B. Barr, and Robin Whyatt.

EHP is published by the National Institute of Environmental Health Sciences, National Institutes of Health, Public Health Service, U.S. Department of Health and Human Services. EHP is an open-access journal, and all content is available free online at http://www.ehponline.org/. Brogan & Partners Convergence Marketing handles marketing and public relations for the publication and is responsible for creation and distribution of this press release.

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