Monday, June 25, 2018 by Isabelle Z.
We all know that pesticide exposure is bad, whether it comes from the food you eat or you happen to live or work on a farm. You might think you can get away with a few non-organic fruits here and there or that a couple hours working on the farm won’t be enough to hurt you. Unfortunately, this line of reasoning could come back to haunt you as a new study shows that even low-level exposure to pesticides can raise your risk of Parkinson’s disease.
Researchers from the University of Guelph reached this conclusion after studying the stem cells of people with Parkinson’s disease who had a genetic mutation in the synuclein gene, which is highly associated with a greater risk of the illness. They compared this to normal stem cells that they had introduced the mutation into using gene editing.
They used these stem cells to create dopamine-producing neurons like those affected when a person has Parkinson’s and then exposed them to two commonly used agrochemicals: maneb and paraquat. Upon exposure, the mitochondria in the cells weren’t able to get where they needed to go within the cell, which had the effect of depleting the neurons’ energy.
This problem occurred below the doses that the EPA has identified as the lowest observed effect level in the neurons of people with Parkinson’s and those with the introduced genetic risk factor. It took a higher dose to impair the function of normal neurons, however.
Study author Scott Ryan remarked that those who are predisposed to Parkinson’s are more vulnerable to low-level agrochemical exposure than others and thus have a higher risk of developing the disease. This, he said, partly explains why those who live in agricultural areas have a higher risk of Parkinson’s.
Just how much greater is the risk? According to Ryan, those exposed to these chemicals have a 250 percent higher risk of going on to develop Parkinson’s than the general population.
Scientists have known that chemical exposure was an influencing risk for Parkinson’s since 1998, but this was one of the first studies to look at what actually happens inside of human cells. Their findings are published in the Federation of American Societies for Experimental Biology.
Ryan is calling for a reassessment of the currently accepted levels of the two chemicals. Because different people have different susceptibility levels, the standards need to be updated to protect everyone. Many of the people who have a higher risk aren’t even aware that they’re so vulnerable.
Past studies have shown that exposure to pesticides doesn’t just raise a person’s risk of developing Parkinson’s; it can even cause the illness in some people. In addition to the paraquat and maneb examined in this most recent study, past studies have also linked the agrochemical ziram to the illness.
The symptoms of this neurodegenerative disorder typically develop slowly over time and might include tremors, balance problems and limb rigidity. In addition to motor symptoms, patients can also experience non-motor symptoms like constipation, cognitive impairment, depression, sleep disorders, and a loss of their sense of smell.
Although people suffering from the illness can have a good quality of life with the right treatment, scientists are working hard to find biomarkers for the disease to help people get an earlier diagnosis and improve their outcomes. By the time it’s discovered, most people have already lost more than half of their brain’s dopamine-producing neurons. Current therapies can improve the symptoms but don’t slow the disease’s progression.
Read Pesticides.news for more coverage of the dangers of pesticide exposure.
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