Herbicide and Pesticide Exposure Linked to Parkinson’s Disease

Parkinson's disease and farm workers

Photo Courtesy of National Farm Worker Ministry

By Case Adams, Naturopath

The possibility that Parkinson’s disease is linked with pesticide exposure has been suggested by naturalists and naturopaths, but there has been little proof. No longer.

A recent study from UCLA has confirmed that exposure to the herbicide Paraquat is linked with a heightened risk of Parkinson’s disease. This combines with other research finding that herbicides and pesticides increase the risk of Parkinson’s.

The researchers, from UCLA’s Fielding School of Public Health, studied 357 Parkinson’s disease cases along with 754 control subjects – adults from Central California. The researchers determined increased exposure to the herbicide Paraquat through geographic mapping of their home addresses, together with agricultural use of the chemical on nearby farms. The research found that those living closer to farms that sprayed the herbicide were found to have a 36% increased risk of Parkinson’s.

However, those who experienced a head injury combined with increased Paraquat exposure tripled their chances of having Parkinson’s disease.

Researchers from Mexico’s Unidad de Medicina Familiar also studied cases of Parkinson’s together with exposure to the herbicide Paraquat among Mexican workers. They also found a positive association between exposure to this chemical and Parkinson’s disease.

Paraquat is N,N′-dimethyl-4,4′-bipyridinium dichloride.

Learn safe detoxification methods.

Realnatural reported initial findings last year from the Louvain Center for Toxicology and Applied Pharmacology of Brussels’ Catholic University of Louvain on pesticide exposure and Parkinson’s. Here the researchers analyzed and calculated the data from twelve peer-reviewed clinical studies that investigated Parkinson’s disease together with pesticide exposure. They collected research conducted between 1985 and 2011.

Their meta-analysis found that all twelve studies individually and combined, established a link between pesticide exposure and Parkinson’s disease.

After calculating meta-data ratios and relative risk, the researchers found that Parkinson’s disease incidence as diagnosed by a neurologist was more than two-and-a-half times for those exposed to more pesticides compared to those less exposed. Other risk calculations showed the increased incidence of Parkinson’s disease to range from nearly double to 28% – which was the average of all cases studied.

But when the research focused upon farm workers involved in the growing of bananas, pineapples or sugarcane, the incidence of Parkinson’s disease more than doubled that of lower-exposure individuals.

The researchers concluded:

“The present study provides some support for the hypothesis that occupational exposure to pesticides increases the risk of Parkinson’s disease.”

Since this review study came out, other studies have investigated some of the worst pesticides, and the mechanisms by which they produce Parkinson’s disease.

A study from Korea’s Yonsei University studied the broad spectrum pesticide Rotenone – and how it damages nerve cells and pathways. The researchers found that Rotenone induces cell death in a process called with G2/M cell cycle arrest. G2/M cell cycle arrest blocks the process of mitosis that enables cells and their DNA to replicate – and more importantly among nerve cells – repair any DNA damage. Thus the insecticide basically blocks the ability of the nerve cell to repair itself – lending to the cells eventually dying off or mutating.

Meanwhile, researchers from UCLA’s David Geffen School of Medicine found that the fungicide Benomyl will block multiple cell processes. One of these blocks the production of aldehyde dehydrogenase (ALDH). This increases the dopamine metabolite 3,4-dihydroxyphenylacetaldehyde, which produces degeneration among neurons associated with the production of dopamine. One of the central dopamine-producing centers exists in the brain – the substantia nigra located within the midbrain.

When the nerve cells located in this region die off or become otherwise deranged, they stop producing dopamine and other neurotransmitters that help control coordination and movement throughout the body. A lack of these neurotransmitters will produce the shakiness and eventual loss of coordination characteristic amongst progressed Parkinson’s patients.

Is eating non-organic food worth risking the health of not only our children and family? Is it worth risking the health of farm workers who are exposed to these toxic chemicals every day? And what about spraying pesticides and herbicides around the house?


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Case Adams is a California Naturopath with a PhD in Natural Health Sciences, and Board Certified Alternative Medicine Practitioner. He has authored 26 books on natural healing strategies. “My journey into writing about alternative medicine began about 9:30 one evening after I finished with a patient at the clinic I practiced at over a decade ago. I had just spent the last two hours explaining how diet, sleep and other lifestyle choices create health problems and how changes in these, along with certain herbal medicines and other natural strategies can radically yet safely turn ones health around. As I drove home that night, I realized I needed to get this knowledge out to more people. So I began writing about health with a mission to reach those who desperately need this information. The strategies in my books and articles are backed by scientific evidence along with wisdom handed down through traditional medicines for thousands of years.” Case connects with the elements by surfing, hiking and being a beach bum.

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