DDT exposure linked to Alzheimer’s disease: “A new study links exposure to the insecticide DDT with Alzheimer’s disease.” Researchers found that 80% of patients with Alzheimer’s had evidence of exposure to the pesticide, which was widely used from the 1940s to 1972 to kill mosquitos that cause malaria. About 70% of people without Alzheimer’s also had evidence of DDT exposure, but the levels of DDE, a breakdown product of DDT, “were nearly four times higher in the blood of people with Alzheimer’s.” DDT was banned by the Environmental Protection Agency in 1972 due to concerns about the risk to wildlife, but “DDT persists in the environment and in human blood and tissue.