A new study of individuals treated for Parkinson’s disease in Louisiana found a clear correlation between the disease and the use of two types of herbicide and one pesticide in rural areas dominated by forestry, woodlands and pastures.
The study also found that Parkinson’s disease has become less common in areas of the state where cotton, corn and soybean farmers have switched to the use of the herbicide glyphosate, sold under the brand name of Roundup — although that product has recently been linked to some forms of cancer, which the study did not examine. Roundup is manufactured in Luling by the Bayer subsidiary Monsanto.
The peer-reviewed, open-access study by three LSU researchers was published online in the International Journal of Environmental Research and Public Health on Feb. 29.
Parkinson’s disease involves the progressive degeneration of the nervous system, and its symptoms include tremors, muscular rigidity, and slow, imprecise movements. It mostly affects middle-aged and elderly people, and its onset can take six to 10 years before symptoms are recognized.
The study found that in the seven-year period ending in 2012, the areas at greatest risk included large portions of Allen and Evangeline parishes, where between 35 and 46 individuals per 10,000 residents were treated for Parkinson’s in hospitals. That band of high risk stretched across the lower middle of the state from Beauregard Parish to Iberville Parish, where farm pastures and timberland are dominant.
The second greatest risk area for that time period runs in a band from Sabine Parish — on the Sabine River along the Texas border — northeast to West Carroll Parish. Again, much of the area is dominated by timber and pastureland, with the exception of West Carroll, where cotton, soybeans and sorghum are grown…