When researchers compared the blood tests of people with Alzheimer’s disease with tests performed on healthy people, they were shocked to find quadruple amounts of a dangerous toxin in the Alzheimer’s folks. If you encounter this chemical, your brain may be in danger.
The case-control study analyzed blood from more than 160 people and discovered that, on average, a metabolite of DDT (dichlorodiphenyltrichloroethane), the banned pesticide, was four times higher in the blood of Alzheimer’s patients.
“This is one of the first studies identifying a strong environmental risk factor for Alzheimer’s disease,” says researcher Allan Levey, M.D., Ph.D., director of Emory’s Alzheimer’s Disease Research Center and chair of neurology at Emory University School of Medicine. “The magnitude of the effect is strikingly large — it is comparable in size to the most common genetic risk factor for late-onset Alzheimer’s.”
Even though use of DDT is illegal in the U.S. today, it can persist in the environment and may be on food that is imported from other countries.
“We are still being exposed to these chemicals in the United States, both because we get food products from other countries and because DDE (a DDT metabolite) persists in the environment for a long time,” says researcher Jason Richardson.
The scientists think that in the brain, both DDT and DDE can lead to the buildup of the proteins that stimulate the formation of damaging plaque. The plaque, containing beta-amyloid, contributes to the brain destruction of Alzheimer’s.
In the U.S., DDT has been banned since 1972. In 2006, the World Health Organization advocated the use of DDT to fight mosquitoes in Africa that carry malaria.