Photo credit: Akash Kurdekar

A study published in the scientific journal Environmental International has detected a link between exposure to organochlorine pesticides and low cognitive scores in the elderly living in the United States. Cognitive function was assessed from 644 participants ages 60 – 85 from the National Health and Nutrition Examination Survey from 1999 to 2002 who did not display signs of overt dementia. Subjects were assessed for exposure to six organochlorine pesticides as well as organophosphate and pyrethroid pesticides. Researchers found that while exposure to non-persistent pesticides such as organophosphates and pyrethroids were not associated with changes in cognitive score, organochlorine pesticides were. Elders with high DDT, DDE, and β-hexachlorocyclohexane had two to three times higher risk for low cognition. Those in the top 5 percent or DDT exposure showed 6.5 times higher risk of low cognition. The authors conclude, “The potential role of background exposure to organochlorine pesticides in the development of dementia should be explored in future prospective studies”.