How Pesticides Can Cause Parkinson’s

Foreign chemicals may prevent brain from disposing of its own toxic waste

Many studies over the past decade have pointed to pesticides as a potential cause of Parkinson’s disease, a neurodegenerative condition that impairs motor function and afflicts a million Americans. Yet scientists have not had a good idea of how these chemicals harm the brain. A recent study suggests a possible answer: pesticides may inhibit a biochemical pathway that normally protects dopaminergic neurons, the brain cells selectively attacked by the disease. Preliminary research also indicates that this pathway plays a role in Parkinson’s even when pesticides are not involved, providing an exciting new target for drug development.

Past studies have shown that a pesticide called benomyl, which lingers in the environment despite having been banned in the U.S. in 2001 because of health concerns, inhibits the chemical activity of aldehyde dehygrogenase (ALDH) in the live. Researchers at the University of California, Los Angeles, U.C. Berkeley, The California Institute of Technology and the Greater Los Angeles Veterans Affairs Medical Center wondered whether pesticide might also affect levels of ALDH in PAL, a naturally forming toxic chemical, rendering it harmless.