On-the-job pesticide exposure is linked to Parkinson's disease

Friday, October 09, 2009 by: S. L. Baker, features writer
Tags: pesticides, health news, Natural News

(NaturalNews) According to the National Institute of Neurological Disorders and Stroke, Parkinson's disease (PD) belongs to a group of conditions called motor system disorders which are the result of the loss of brain cells that produce the neurotransmitter dopamine. That's the critical key in the development of PD because dopamine's many functions in the brain include voluntary movement, cognition, learning, sleep, mood and more. So when PD strikes, it means dopamine in the body is disrupted and tremor, trembling, muscle rigidity, slowness of movement, sleep disruptions, dementia and a host of other problems can develop over time.

But what causes PD to strike in the first place? What happens to those dopamine producing brain cells that causes this cascade of symptoms? For most cases, doctors usually just say it is idiopathic -- meaning no one knows. But a growing body of research has accumulated over the past year that points to a particular class of toxins that seem to be behind at least a significant portion of Parkinson's disease suffering. The culprit? Pesticides.

Parkinson's disease and pesticides

Now comes yet another study showing an association between PD and pesticides. This one, just published in the Archives of Neurology, shows people whose occupations put them in contact with pesticides appear to have a dramatically increased risk of Parkinson's. It had some surprises -- occupations involving agriculture, education, health care, or welding were not associated with an increased risk of PD in this study but ever working in business and finance, legal occupations, construction or transportation and material moving was especially associated with a subtype of PD marked by gait disturbances.

Dr. Caroline M. Tanner of the Parkinson's Institute in Sunnyvale, California, and her research team studied 519 people suffering from with PD along with 511 controls who were the same age and sex and lived in the same location. The research subjects were questioned about their work history and exposure to toxic chemicals, including solvents and pesticides. The results showed that among people with Parkinson's disease, occupational pesticide exposure was associated with a significantly increased risk of the disease. Forty-four (8.5 percent) PD patients reported pesticide exposure on the job compared to 27 (5.3 percent) of the people in the control group.

The researchers point out in their study that while there is growing evidence suggesting a cause and effect association between pesticide use and PD, the term "pesticide" is broad and includes many chemicals and mechanisms of use. "Because few investigations have identified specific pesticides, we studied eight pesticides with high neurotoxic plausibility based on laboratory findings. Use of these pesticides was associated with higher risk of parkinsonism, more than double that in those not exposed," the scientists wrote. They found three specific, individual compounds that tripled the risk of PD: an organochloride (2,4-dichlorophenoxyacetic acid), an herbicide (paraquat) and an insecticide (permethrin). What's more, all three of these chemicals have already been shown in previous laboratory research to impact the dopamine producing brain cells that are affected by Parkinson's disease.

"This convergence of epidemiologic and laboratory data from experimental models of Parkinson's disease lends credence to a causative role of certain pesticides in the neurodegenerative process," the authors conclude. "Other pesticide exposures such as hobby gardening, residential exposure, wearing treated garments or dietary intake were not assessed. Because these exposures may affect many more subjects, future attention is warranted."

As previously covered by NaturalNews, another study earlier this year found the pesticide B-hexachlorocyclohexane (B-HCH) also appears to be a strong trigger for PD(https://www.naturalnews.com/026842_disease_Pa...). In addition, a University of California at Los Angeles (UCLA) study placed pesticides at the top of the list of probable causes of Parkinson's. That research, published in the American Journal of Epidemiology, showed exposure to a combination of two widely used pesticides increased the risk of PD by an incredible 75 percent (https://www.naturalnews.com/026177_disease_Pa...).

For more information::
http://www.ncbi.nlm.nih.gov/pubmed/19752299?...
http://www.ninds.nih.gov/disorders/parkinson...