American researchers looked at 4,000 senior residents (aged 65 and older) of an agricultural county in Utah. The study participants were assessed for cognitive function (e.g. memory, attention span, and problem solving) at the start of the study was given at the outset and two other times over a six- to seven-year period and interviewed about exposure to environmental toxins such as pesticides.
The study results showed that pesticide exposure increases the likelihood of developing Alzheimer’s by 53%. The results were reported at the Alzheimer’s Association 2009 International Conference on Alzheimer’s Disease in Vienna, Austria last July.
Although Alzheimer’s has been closely linked to genetic factors, it hasn’t been clear while some individuals get and some not, regardless of genetic predisposition. Experts believe that environmental factors, e.g. pollutants and toxins may play a role.
Pesticides are environmental toxins that have been linked to a lot of chronic diseases including cancer. It may also have some long-term harmful effects on the nervous system that can lead to dementia and Alzheimer’s.
According to author Dr. Kathleen M. Hayden of Duke University Medical Center in Durham, N.C.
The researchers say that the use of pesticides has increased during the last 50 years, mainly in agriculture. It is estimated that in the US alone, more than 2 billion pounds of the 18,000 licensed pesticides are used and released into the environment.
Certain pesticides are believed to interfere with the production and release of acetylcholine, a neurochemical that plays a major role in memory.
The study results alone are not enough proof that pesticides cause Alzheimer’s. However, the association is so strong that it warrants further investigation of the role of environmental toxins (pesticides as well as others) in the pathogenesis of Alzheimer’s.
According to Dr. Ralph Nixon, vice chairman of the Medical and Scientific Advisory Council at the Alzheimer’s Association and an Alzheimer’s expert at New York University
“You can look at environmental toxins as being something that promotes the root cause of the disease, or as a second hit. If someone is already predisposed to Alzheimer’s due to genetics, cardiovascular disease, or some other risk factor, the environmental toxin may push their risk over the top,”