(Beyond Pesticides, December 6, 2013) In a new study exploring gene-environment interactions, researchers find that individuals with a genetic mutation linked to Parkinson’s disease are more likely to develop the neurodegenerative disease if they are exposed to pesticides. The study, Isogenic Human iPSC Parkinson’s Model Shows Nitrosative Stress-Induced Dysfunction in MEF 2-PGC1α Transcription, identifies the molecule that protects neurons from pesticides, ties genetic mutation to pesticide exposure, and demonstrates that low dose exposure can cause Parkinson’s disease. The study, conducted by researchers at the Massachusetts Institute of Technology and the Sanford-Burnham Medical Research Institute in La Jolla, CA, supports previous epidemiological and animal studies that demonstrate the link between pesticide exposure and neurological damage, using human stem cells as a model. “For the first time, we have used human stem cells derived from Parkinson’s disease patients to show that a genetic mutation combined with exposure to pesticides creates a ‘double hit’ scenario, producing free radicals in neurons that disable specific molecular pathways that cause nerve-cell death,” says lead author Stuart Lipton, M.D., Ph.D., professor and director at the Sanford-Burnham’s Medical Research Institute. Using skin cells from Parkinson’s patient who already possess the genetic mutation linked to the disease, researchers transformed […]

(Beyond Pesticides, October 3, 2013) According to new research, residents are more highly exposed to organophosphate and pyrethroid pesticides in New York City (NYC) than in the U.S. overall.  Researchers from the city’s Department of Health and Mental Hygiene reviewed the 2004 NYC Health and Nutrition Examination Survey (NYC HANES) to compare its pesticide exposure patterns in an urban environment with the nation as a whole. The NYC HANES includes a biomonitoring component to evaluate pesticide exposures by measuring concentrations of organophosphate and pyrethroid metabolites in urine. According to the authors, the findings underscore the importance of considering pest and pesticide burdens on cities, where a dense population results in a single exposure source affecting many people at the same time when regulating pesticide use. Organophosphate metabolites were measured in the urine of 882 New Yorkers, while 1,452 residents were tested for pyrethroid metabolites. As the researchers explain, the building density and disrepair in parts of NYC likely increased the chances of a pest infestation, which in turn can lead to the reliance on indoor pesticide use. By the 1980’s, organophosphates were the most common class of insecticides in the U.S., and were used indoors until the early 2000’s when […]

(Beyond Pesticides, May 30, 2013) New research published in the journal Neurology further supports the causative link between pesticide exposure and Parkinson’s disease. Emanuel Cereda, M.D., Ph.D., of the IRCCS university Hospital San Matteo Foundation in Pavia, Italy, and coauthor Gianni Pezzoli, M.D., analyzed 104 studies published between 1975 and 2011 to determine the link between pesticides and solvents to Parkinson’s disease. The researchers analyzed exposure using information on proximity to large farms likely to use pesticides, likelihood of well water consumption, and occupations that cause greater exposure to pesticides and solvents used to kill weeds, insects, fungus, and rodents. Overall, researchers found exposure to pesticides increased the risk of developing the disease by 33%  to 80%.   Some pesticides were considered to be of higher risk than others, with weed killers like paraquat and fungicides maneb and mancozeb causing twice the risk for development of Parkinson’s disease. While risk increased the longer people were exposed to pesticides, researchers indicate there is still a need for further research on the chemical threshold for harm to the brain. The study builds on recent research that has linked Parkinson’s disease to pesticide exposure. In a 2011 article published in the journal Molecular […]

(Beyond Pesticides, May 9, 2013) A review of the scientific literature of the toxic effects of glyphosate, one of the most popular weed killers in the U.S. and the active ingredient in Roundup, links the herbicide  to a wide range of diseases and suggests  that more research is needed. The review, conducted by a scientist at Massachusetts Institute of Technology (MIT), looks at the mechanisms through which the adverse effects may be happening and points to  the chemical’s inhibition of cytochrome P450 (CYP) enzymes, which plays the crucial role of detoxifying xenobiotics. Thus, glyphosate can enhance the negative effects of other environmental toxicants on the body. Authors argue that this has been a critically overlooked component in research on glyphosates’ toxicity to mammals. We “have hit upon something very important that needs to be taken seriously and further investigated,” Stephanie Seneff, PhD, lead author and research scientist at MIT, told Reuters. Not surprisingly, Monsanto, the developer of Roundup, the leading product containing glyphosate, has attempted to discredit the study, claiming that its product has a long track record of being safe – read Another Bogus “Study.” However, Beyond Pesticides has assembled  extensive documentation on the human health and environmental risks […]

(Beyond Pesticides, April 29, 2013) Dow AgroSciences, one of the nation’s largest pesticide makers, along with various food companies, have persuaded several members of Congress to endorse a bill that directs the Environmental Protection Agency (EPA) to reverse a proposed phase out of sulfuryl fluoride, a highly toxic food fumigant and potent greenhouse gas. If passed, the bill would make the U.S. one of only two western nations to allow sulfuryl fluoride on food, increase the number of American children ingesting unsafe levels of fluoride, and create a food poisoning risk for consumers who  purchase food that contains permissible levels of the fumigant. The  Pest Free Food Supply Act, H.R. 1496, sponsored by Rep. Tom Graves (R-GA) and 14 others, seeks to prevent the proposed  phase out  of sulfuryl fluoride from taking effect. The phase out, which EPA proposed in January 2011, was prompted by a  joint petition from the Fluoride Action Network (FAN), Environmental Working Group (EWG) and Beyond Pesticides. In seeking to prevent the phase out from taking effect, the bill’s sponsors have adopted Dow’s widely discredited talking points on the safety and necessity of sulfuryl fluoride fumigation. The public should know: ”¢ Of the few western nations […]

(Beyond Pesticides, January 8, 2013) Neurologists at the University of California, Los Angeles (UCLA) have published their latest research linking pesticide exposure to Parkinson’s disease. Appearing in the online edition of PNAS, the UCLA scientists’ work details the series of events that can occur after individuals are exposed to the pesticide benomyl, which was phased out in 2001. Researchers believe their findings on the series of events the pesticide sets in motion could be applicable even to Parkinson’s patients who have not been exposed to benomyl. According to scientists, exposure to benomyl prevents the enzyme aldehyde dehydrogenase (ALDH) from keeping in check a naturally occurring toxin in the brain called 3,4-Dihydroxyphenylacetaldehyde (DOPAL). Without ALDH regulating DOPAL, the toxin accumulates, damages neurons, and increases an individual’s risk of developing Parkinson’s disease. Researchers postulate that this process may be occurring in people with Parkinson’s who were never exposed to pesticides. The findings of this research provide insight into possible treatments to slow the disease, such as developing new drugs to protect ALDH activity. Although the exact cause of Parkinson’s is still unknown, until this research scientists were focusing in on the protein a-synuclein as a pathway to the disease. The protein, present […]

(Beyond Pesticides, December 10, 2012) Long-term low-level exposure to organophosphate pesticides produces lasting damage to neurological and cognitive functions, according to researchers at University College London (UCL). This research pulls data from 14 studies over the past 20 years, including more than 1,600 participants, in order to provide a quantitative analysis of the current literature on these dangerous chemicals. Lead author of the study, Sarah Mackenzie Ross, Ph.D., notes, “This is the first time anyone has analyzed the literature concerning the neurotoxicity of organophosphate pesticides, using the statistical technique of meta-analysis.” UCL’s systematic review, published in the journal Critical Reviews in Toxicology, comes to an unsettling conclusion about the hazards of constant low-level occupational exposure to organophosphates. The study notes, “The majority of well designed studies found a significant association between low-level exposure to [organophosphates] and impaired neurobehavioral function which is consistent, small to moderate in magnitude and concerned primarily with cognitive functions such as psychomotor speed, executive function, visuospatial ability, working and visual memory.” In other words, low-level exposure had significant detrimental effect on working memory and information processing. The researchers are hopeful that the results of their analysis will be used to inform governments performing reviews on the […]

(Beyond Pesticides, November 14, 2012) For years, scientists have shown that pesticide exposures are linked to the onset of Parkinson’s disease. Now a new study by researchers at University of California, Los Angeles, (UCLA) finds that exposure to pesticides and suffering a head injury are associated with a three-fold increase in one’s chances of developing Parkinson’s disease. Parkinson’s disease is the second most common neurodegenerative disease, and occurs when nerve cells in the substantia nigra region of the brain are damaged or destroyed and can no longer produce dopamine, a nerve-signaling molecule that helps control muscle movement. People with Parkinson’s disease have a variety of symptoms, including loss of muscle control, trembling and lack of coordination. Over time, symptoms intensify. At least one million Americans have Parkinson’s and about 50,000 new cases are diagnosed each year. The study, “Traumatic brain injury, paraquat exposure, and their relationship to Parkinson disease,” published in the journal Neurology surveyed more than 1,000 adults ages 35 and older who lived in central California. Some 357 of the participants were diagnosed with Parkinson’s disease. Participants with the disease were nearly twice as likely as those without the disease to report having had a head injury in […]

(Beyond Pesticides, June 29, 2012) New research from the McGill University Health Centre (MUHC) in Montreal suggests that pesticide exposure, as well as smoking, head injury, farming, and less education, may be a risk factor for a rare sleep disorder that causes people to kick or punch during sleep, according to a study entitled “Environmental risk factors for REM sleep behavior disorder: A multicenter case-control study” published in the June 27, 2012, online issue of Neurology, the medical journal of the American Academy of Neurology. People with the disorder, called REM sleep behavior disorder, do not have the normal lack of muscle tone that occurs during rapid eye movement (REM) sleep, causing them to act out their dreams. The movements can sometimes be violent, causing injury to the person or their bed partner. The disorder is estimated to occur in 0.5 percent of adults. “Until now, we didn’t know much about the risk factors for this disorder, except that it was more common in men and in older people,” said study author Ronald B. Postuma, MD, MSc, with the Research Institute at MUHC and a member of the American Academy of Neurology. “Because it is a rare disorder, it was […]

(Beyond Pesticides, June 15, 2012) Researchers at the Duke University School of Medicine have developed a laboratory screening system for detecting neurotoxic chemicals and successfully tested it on more than 1,400 potential toxicants. The study confirms the high toxic activity of the chemical piperonyl butoxide (PBO), a chemical “synergist” used to increase the potency of more than 700 insecticides, including synthetic pyrethroids widely used in mosquito and community spray programs and for home use. The study, entitled “The Insecticide Synergist Piperonyl Butoxide Inhibits Hedgehog Signaling: Assessing Chemical Risks,” was published in the May 2012 edition of the journal Toxicological Sciences. The testing shows that PBO disrupts a biological signaling system that is “critical in neurological development,” the researchers reported in the abstract of their paper. The study finds that the disruption of this critical pathway “may be the molecular basis for profound developmental defects in children exposed in utero to PBO.” Piperonyl butoxide is not itself classified as a pesticide, but companies combine it with insecticides to increase their potency. PBO came into widespread use when the U.S. Environmental Protection Agency (EPA) phased out chlorpyrifos and other organophosphate pesticides nearly a decade ago after determining that they posed a risk […]

(Beyond Pesticides, April 13, 2012) A study has found that the children of flower plantation workers in Ecuador are neurologically affected by the pesticide residues that their parents unwittingly carry home on their clothes, tools, and skin. The study documents significantly reduced activity for the essential enzyme acetycholinesterase (AChE) in children whose parents work on flower plantations compared to others whose parents do not. The two main classes of pesticides that the researchers identify as used in the region’s flower production, organophosphates and carbamates, are known to suppress the enzyme’s activity. AChE activity is crucial to healthy neurological functioning in humans and its suppression during childhood can hinder nervous system and cognitive development causing immediate and long-term impairment. In the study, Lower acetylcholinesterase activity among children living with flower plantation workers (Environ Res. 2012 Apr;114:53-9. Epub 2012 Mar 10), children whose parents work on a flower plantation are more than three times more likely to be in the group of lowest AChE activity. Additionally, the children who live the longest with a flower plantation worker are four times more likely to have lower enzyme activity than children who never live with a plantation worker. The researchers obtained their results by […]

(Beyond Pesticides, August 11, 2011) A combination of eleven different kinds of commonly used pyrethroids were tested on mice in a new study which found that, at real-world exposure levels, the insecticides can produce heightened toxicity that is equal to the sum of each insecticide’s individual effect. The mixture of similar-acting insecticides works by over-stimulating electronic channels in the mouse’s brain cells and eventually causing death. This study adds to the growing body of research on the toxicity of pesticide combinations in nature and showcases the need for policy change because the current risk assessment approach to regulating pesticides fails to look at chemical mixtures and synergistic effects. The U.S. Environmental Protection Agency (EPA) currently regulates on a chemical-by-chemical basis, but as this study demonstrates, interacting chemicals can have synergistic effects at very low levels, where a “chemical cocktail” of multiple interacting chemicals combine to have greater effects than expected. Pesticides can also have a cumulative “toxic loading” effect both in the immediate and long term. Researchers exposed mice brain cells to eleven different food-use pyrethroid insecticides either singly or in a mixture in the study entitled ”Additivity of pyrethroid actions on sodium influx in cerebrocortical neurons in primary culture.” […]

(Beyond Pesticides, June 28, 2011) Recent studies have linked Parkinson’s disease to pesticide exposure. In a new article published in the journal Molecular Neurodegeneration, researchers at the University of Missouri School of Medicine take some of the first steps toward understanding this link and unraveling the molecular dysfunction that occurs when proteins are exposed to environmental toxins. The study, “Oxidation of the cysteine-rich regions of parkin perturbs its E3 ligase activity and contributes to protein aggregation,” helps further explain recent NIH findings that demonstrate the link between Parkinson’s disease and two particular pesticides — rotenone and paraquat. “Fewer than 5 percent of Parkinson’s cases are attributed to genetics, but more than 95 percent of cases have unknown causes,” said Zezong Gu, MD, PhD, assistant professor of pathology and anatomical sciences. “This study provides the evidence that oxidative stress, possibly due to sustained exposure to environmental toxins, may serve as a primary cause of Parkinson’s. This helps us begin to unveil why many people, such as farmers exposed to pesticides, have an increased incidence of the disease.” Scientists previously understood that Parkinson’s is associated with oxidative stress, which is when electronically unstable atoms or molecules damage cells. The MU study yields […]

(Beyond Pesticides, May 31, 2011) A study has found that people whose workplaces were close to fields sprayed with chemicals — not just those who live nearby — are at higher risk of developing Parkinson’s disease (PD). The pesticide chemicals in question include two fungicides -maneb (in the ethylene bisdithiocarbamate (EDBC) family and ziram (in the dimethylthiocarbamate family)- and the herbicide paraquat that appear to raise the risk of developing the movement disorder. In a study published in the European Journal of Epidemiology, entitled, “Parkinson’s disease risk from ambient exposure to pesticides,” a team of researchers led by UCLA neurologist Beate Ritz, PhD found that exposures to the trio of pesticides are actually higher in workplaces located near sprayed fields than they were in residences. And the combination of exposure to all three pesticides, which act in different ways to harm brain cells involved in Parkinson’s disease, appears to be cumulative, the team led by Dr. Ritz concludes. The study found that the combined exposure to pesticides ziram, maneb and paraquat near any workplace increased the risk of Parkinson’s disease threefold, while combined exposure to ziram and paraquat alone was associated with an 80% increase in risk. The researchers estimate […]

(Beyond Pesticides, February 17, 2011) According to a recent investigative report, a company known for conducting scientific research for the pesticide industry has, in an attempt to refute research linking pesticides to Parkinson’s disease, paid a U.S. government agency, the National Institute for Occupational Safety and Health (NIOSH), to prove that certain pesticides are safe. According to the report, the company, Exponent Inc., is a member of CropLife America, a trade group that represents pesticide manufacturers, and also has worked regularly for Syngenta, which makes paraquat, one of the chemicals it is looking prove as safe. Specifically, the company is looking to refute the research which shows that even small amounts of agricultural chemicals, maneb and paraquat, when combined, can raise the risk of Parkinson’s disease. According to the report, managing scientist of Exponent, Laura McIntosh, PhD, said in an interview that the company donated the money and sought participation at NIOSH to enhance the credibility of its study of maneb and paraquat; they wanted to make their research “bulletproof.” NIOSH is a division of the Centers for Disease Control and Prevention (CDC). Generally, government agencies are supposed to be unbiased, and federal ethics rules prohibit employees from accepting money […]

(Beyond Pesticides, February 16, 2011) Many agricultural pesticides —including some previously untested and commonly found in food— disrupt male hormones, according to new tests conducted by British scientists. Meanwhile, U.S. researchers at the National Institutes of Health have found that people who used two specific varieties of pesticide were 2.5 times as likely to develop Parkinson’s disease. Pesticides Impact Male Hormones Evidence suggests that there is widespread decline in male reproductive health and anti-androgenic pollutants, also known as endocrine disruptors, may play a significant role. Thirty out of 37 pesticides tested by the researchers at the University of London altered male hormones, including 16 that had no known hormonal activity until now. There was some previous evidence for the other 14. Most are fungicides applied to fruit and vegetable crops, including strawberries and lettuce. The study, “Widely Used Pesticides with Previously Unknown Endocrine Activity Revealed as in Vitro Anti-Androgens,” is published in Environmental Health Perspectives. The British researchers screened the chemicals using in vitro assays, which use human cells to check whether the pesticides activate or inhibit hormone receptors in cells that turn genes on and off. Scientists, however, are uncertain what actually happens in the human body at the […]

(Beyond Pesticides, Aug 2, 2010) A new report conducted by an Ann Arbor, Michigan based coalition of health and environmental groups estimates that children’s exposure to toxic chemicals, including pesticides, cost Michigan billions of dollars each year. The study examines the costs associated with four environmentally related childhood diseases: lead poisoning, asthma, pediatric cancer, and neurodevelopmental disorders. Treating these four disorders costs the state of Michigan an average of $5.85 billion annually. The study, “The Price of Pollution: Cost Estimates of Environment-Related Childhood Disease in Michigan” was released in time for the US House Energy and Commerce Committee hearings on the Toxic Chemicals Safety Act of 2010, an overhaul of the 1976 Toxic Substances Control Act (TSCA). Using conservative estimates researchers consider direct costs such as medical treatment, as well as less direct costs such as parent wage losses. The study also notes the substantial emotional costs to families dealing with these potentially life threatening or debilitating conditions which cannot be quantified. Lead poisoning is found to be the most costly of the diseases studied, costing on average $4.85 billion annually, followed by childhood asthma, pediatric cancer, and neurodevelopmental disorders. These four disorders alone cost the state of Michigan 1.5% […]

(Beyond Pesticides, June 16, 2010) Men with certain genetic variations who were exposed to some toxic pesticides that are now largely banned run an increased risk of developing Parkinson’s disease, French scientists said Monday. In a study published in Archives of Neurology, entitled “Interaction Between ABCB1 and Professional Exposure to Organochlorine Insecticides in Parkinson Disease,” French researchers found that among men exposed to pesticides such as DDT, carriers of the gene variants are three and a half times more likely to develop Parkinson’s than those with the more common version of the gene. The scientists think the brains of people with the gene variant fail to flush out toxic chemicals as efficiently as those with common versions of the gene, suggesting that environmental as well as genetic factors are important in the risk of Parkinson’s. Alexis Elbaz, MD, PhD and Fabien Dutheil, PhD, of France’s National Institute for Health and Medical Research (INSERM) studied 101 men with Parkinson’s and 234 without the disease to look at links between organochlorine exposure and Parkinson’s disease. The study includes only men, and all of them had high levels of exposure to pesticides through their work as farmers. The scientists found the link was […]

(Beyond Pesticides, May 28, 2010) The repeated exposure to organophosphate and organochlorine insecticides can increase the risk of developing Alzheimer’s Disease (AD) or dementia later in life according to a new study published in the May issue of Neurology. The observational study entitled “Occupational exposure to pesticides increases the risk of incident AD” is one of very few studies to examine a link between pesticides and AD. Researchers lead by Kathleen M. Hayden, PhD of Duke University Medical Center examined residents 65 years and older from an agricultural community in Cache County Utah. Participants were assessed for cognitive ability at the inception of the study and again after 3, 7, and 10 years. Data showed that those repeatedly exposed to any pesticides were more likely to develop AD or dementia. Researchers found a higher incidence of AD among those exposed to organophosphates and organochlorines. The risk of AD associated with organophosphate exposure was slightly higher than the risk associated with organochlorines. Researchers also found an increase in dementia among those exposed to organophosphates or organochlorines; however this increase was not statistically significant. Dr. Hayden said that more research was necessary to determine a causal link. Organophosphates are known to reduce […]

(Beyond Pesticides, January 11, 2010) Yet another study has been published that further supports the causative link between pesticide exposure and Parkinson’s disease. The study, funded by the National Institute of Environmental Health Sciences (NIEHS), is published in the January issue of Epidemiology. The University of California, Los Angeles researchers looked at the association between Parkinson’s disease, organophosphate pesticides and the common gene variant, paraoxonase-1 gene Leu-Met 55 polymorphism (PON1-55 MM). The findings show that study participants with two copies of gene variant have a significantly increased risk of developing Parkinson’s disease when exposed to certain organophosphate pesticides used in agriculture. The population-based case-control study examined the DNA of 351 incident cases and 363 controls from three rural counties in California. The researchers then used pesticide usage reports and a geographic information system (GIS) approach to determine the study participants’ residential exposure to organophosphates. The PON1 gene codes for an enzyme that metabolizes organophosphate pesticides. Individuals with the variant MM PONI1-55 genotype that are exposed to organophosphates exhibit more than twice the risk of Parkinson’s disease compared to carriers of wildtype or heterozygous genotype and no exposure. In regards to exposure to diazinon, carriers of variant MM PONI-55 genotype show […]

(Beyond Pesticides, September 16, 2009) A new study published in the September issue of Archives of Neurology reports that the risk of Parkinsonism doubled with increased occupational exposure to pesticides, including eight agents associated with experimental Parkinsonism. These data add to the growing number of studies that lend credence to a causative role of certain pesticides in neurological disorders. The study, “Occupation and Risk of Parkinsonism: A Multicenter Case-Control Study,” set out to investigate occupations, specific job tasks, or exposures and risk of parkinsonism in collaboration with eight movement disorders centers in North America including, the Parkinson’s Institute, CA, Department of Neurology, Baylor College of Medicine and Department of Neurology, Beth Israel Medical Center, New York. The investigation focused on five occupations previously suggested as posing an increased risk of Parkinsonism: agriculture, education, healthcare, welding, and mining. This examination of toxicant exposures included solvents and pesticides putatively associated with Parkinsonism. 519 people with Parkinson’s disease and 511 similar people who did not have Parkinson’s were studied. Overall, the study finds that those whose jobs involve using pesticides are 80 percent more likely to develop the condition. The data reveals that any exposure to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) almost triples […]

(Beyond Pesticides, August 12, 2009) A new study examining the effects of the mosquito repellent DEET on insects, mice and human proteins reports that the chemical interferes with a prominent central nervous system enzyme. This effect is magnified when exposure to DEET is combined with exposure to certain other pesticides. Entitled, “Evidence for inhibition of cholinesterases in insect and mammalian nervous systems by the insect repellent deet,” and published in BioMed Central (BMC) Biology, the study utilized toxicological, biochemical and electrophysiological techniques to show that DEET is not simply a behavior-modifying chemical, but that it also inhibits cholinesterase activity in both insect and mammalian neuronal preparations. The researchers examined DEET’s effects on mosquitoes, cockroach nerves, mouse muscles, and enzymes purified from fruit flies and humans. Applications of DEET slowed or halted the actions of the enzyme acetylcholinesterase. This enzyme is crucial for regulating nerve impulses in both insects and mammals, and once its functions are disrupted, neuromuscular paralysis, leading to death by asphyxiation result. In humans, symptoms include headache, exhaustion and mental confusion together with blurred vision, salivation, chest tightness, and muscle twitching and abdominal cramps. The study also investigated the consequences of DEET interactions with carbamate insecticides on the […]

(Beyond Pesticides, August 7, 2009) A recent study published in the journal Environmental Health Perspectives has added to evidence that certain pesticides significantly increase one’s risk of developing Parkinson’s disease (PD). Researchers found that rural residents who drank private well water within 500 meters of fields sprayed with certain pesticides had an increased – up to 90 percent – risk of developing PD, and those with Parkinson’s “were more likely to have consumed private well water, and had consumed it on average 4.3 years longer.” The study evaluated more than 700 people, including carefully chosen controls, in Fresno, Kent, and Tulare counties. 17 percent reported drinking private well water between 1974 and 1999. Researchers focused on wells’ proximity to agricultural fields sprayed with pesticides, since private wells are not regulated, and many are shallow enough to be contaminated by pesticides seeping into groundwater. Researchers looked at 26 pesticides and six in particular, “selected for their potential to pollute groundwater or because they are of interest for PD, and to which at least 10% of our population were exposed.” Those are: diazinon, chlorpyrifos, propargite, paraquat, dimethoate, and methomyl. Propargite exposure was most closely correlated with incidence of PD, with a 90 […]