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Sorry it took so long to report this news. It appeared in the front page of the the Democrat and Chronicle Rochester newspaper September 8th. It was not in the digital addition so we have to copy it here. UR DISCOVERS LINK TO PARKINSON'S STUDY IS THE FIRST TO TIE A BREW OF FARM CHEMICALS TO THE DISEASE. The neurological disorder Parkinson's disease has been linked for the first time to a combination of common agricultural pesticides. In the experiments on mice at the University of Rochester, low levels of herbicide paraquat and the fungicide maneb were injected four times in mice. The injections combined to adversely affect the nervous system, even after few weeks of exposure. Parkinson's is one of the family of chronic neurological disorders marked by trembling, rigid posture and pronounced muscle weakness. There is no cure. It is not inherited, so scientist for years have suspected an environmental agent, especially herbicides. Previous studies have also linked Parkinson's and herbicides, including paraquat, which in a class of pesticides called organophosphates, and fungicides-like maneb-that contain manganese. But the work by UR dean of medical research Deborah A Cory-Slechta is the first time combination of such chemicals has been liked to Parkinson's. "These compounds by themselves do not cause Parkinson's," she said. "They're risk factors that are part of a larger picture, in conjunction with the right genetic background." It's not the first research to measure the untoward synergy of combined chemicals, said Cory-Slechta. But it's the first to reproduce a syndrome that looks like Parkinson's and is the strongest links far) between Parkinson's and pesticides" UR researchers chose to study the interaction of paraquat and maneb because each chemical, at the high doses, weakens the brain's "dopamine" systems, which are necessary to pass along nerve signals related to muscle movement and coordination. And they chose the two because both chemicals are often used in combination on the same farm fields. Maps from the National Center for Food and Agricultural Policy, included in the study show the nationwide distribution of paraquat and maneb, in pounds per square mile of farmland. The maps show overlapping usage of the two chemicals along the northeast coastal corridor, in the Midwest and along the pacific coast. Those are the same areas marked by the highest rate of age adjusted mortality for Parkinson's. Stroke, brain cancer and other disease of the nervous system do not show similar geographic distributions, said Cory-Slechta. She cautioned that there is no data on human exposures to these pesticides. But the overlapping maps, she said "raise concerns we need to look at." Paraquat is a weed killer, usually sprayed aerial on cotton and food crops. Maneb is a fungicide common in farm and home garden applications .The U.S. Environmental Protection Agency's "breadbasket survey" has identified it as a common pesticide residue in processed and fresh foods. Paraquat has not been for identified. The UR studies, call into question the adequacy of current risk assessment guidelines for pesticide use. The effects of such chemicals on human health and typically studied separately and not in combination with other pesticides. Other mixtures of chemicals are likely to show the same "additive effects," which exaggerate toxicity in humans and which may cause illnesses beyond Parkinson's Cory-Slechta said. "The two (pesticides) we threw together for this study are just the tip of the iceberg," she said. "I'm a little bit concerned when people claim synergy like this" said Harold Harlan, an entomologist with the Virginia base National Pest Management Association. There's no system yet for assessing the health risks of multiple chemicals in combination, he said. But the EPA'S cumulative risk project" is taking the first steps to get beyond the single chemical risk model. By 2006, EPA scientist will finish reassessments of the risk of each of 900 active ingredients in the 20,000 pesticide products now on the US market. They will take into account how much of each chemical accumulates in food drinking water and air. And they'll measure how the members of certain chemical families interact with each other. "They've got a pretty full plate right now-it's a big first step said entomologist George Good director of Cornell University's pesticide management education program. Studies of the toxic effects of non related pesticides like paraquat and maneb could be "five, six, seven years down the road, he said ON THE WEB *To learn more about pesticides and Parkinson's disease visit the Environmental Protection Agency online at: www.envadvocates.org *For information on new risk assessments for pesticides, click on the Environmental Protection Agency: epa.gov/pesticides Donna Testa "William P. Taggart" wrote: > Environmental pesticides linked with Parkinson's <<...>> > This report provides further evidence of the effect of environmental > pesticides on Parkinson's disease (PD). Over a 10-year period, mortality > rates associated with PD and ischaemic heart disease were compared across 58 > Californian states, which had been ranked by pesticide use. > The investigators found that mortality from PD, as the underlying cause of > death, was 19-47% higher in states reporting the use of restricted > agricultural pesticides compared with PD mortality in states reporting no > use of restricted pesticides. > Although no dose-response relationship was observed, the risk of dying from > PD was correlated with percentage of land treated for the single year in > which this data was analysed. This research therefore provides evidence that > mortality from PD is correlated with environmental pesticide exposure. > Source: Ritz B & Yu F. International J Epidemiology 2000;29:323-329. Updated > September 2000.