Parkinson's and Pesticides

For those who have emailed sympathies about my broken arm, thanks. It is coming along, and happily, my doctor tells me I can expect to regain "98% of the use of the arm." He says I may never be able to hyperextend the elbow (straightening the arm to the point where the elbow actually pops inward) but, in the big picture, this is a short-term painful nuisance, nothing more.

This week I heard from a dear, old friend who is suffering from more than a painful nuisance. She has been diagnosed with Parkinson's. Coincidentally, the day we exchanged emails, a new study was published in the on-line journal BMC Neurology that helps cement the link between Parkinson's and pesticide exposure.

Most people think of pesticides as something farmers use and are exposed to, but consumers are as well, through the use of lawn & garden products and household insect repellents and antifungals. In this study, scientists did something a bit unique, looking within families at both Parkinson's sufferers and their relatives who don't show symptoms of the disease, studying the families of 319 Parkinson's sufferers, while controlling for age, sex, cigarette smoking, and caffeine consumption. What they found: "Overall, individuals with PD [Parkinson's] were significantly more likely to report direct pesticide application than their unaffected relatives."

The researchers started with a phone questionnaire, asking, "Have you ever applied pesticides to kill weeds, insects, or fungus at or, in your home, in your garden, or on your lawn?" They explained that, "Application of any pesticide chemical by spreading solid granules, spraying by hand, spraying by tractor, spraying by airplane, putting in irrigation water, or placing pest strips or traps, was considered a direct pesticide application".

Anyone who answered yes to the question was then questioned in more detail on the types of pesticides they remembered applying, when they applied it, how frequently they applied it, and other follow up questions. They also followed up with all participants on information about where they lived, where their drinking water came from, where they worked, and other pertinent questions to help define potential pesticide exposures.

The bottom line of their study: Individuals who reported either childhood or adult direct applications of pesticides were 1.61 times more likely to have Parkinson's than those who did not report pesticide use. In statistical terms that is quite significant. Think of it this way, if you apply or applied these chemicals at some point in your life, you are almost twice as likely to get Parkinson's as someone who has never applied them.

I don't know what my friend's exposure history might have been as a child or an adult. I think back to my own child, and remember getting the can of Raid to kill crickets chirping in the house. My husband remembers jabbing weeds in the family lawn with "kill sticks". We have both avoided pesticide applications of any type throughout our adulthoods, but one thing about exposures is that some can come back to haunt us decades after the exposure took place.