Over and over studies have found links with certain toxic chemicals (some pesticides and the chemical trichloroethylene) and Parkinson's disease. Another recent study found that long-term exposure to high levels of the chemical trichloroethylene (TCE) in the outside air increases the risk of developing Parkinson's disease.
TCE is an industrial solvent used in numerous industrial (as a degreaser), consumer, military, and medical applications. For example, it is used in dry cleaning clothes, removing paint, as a degreaser, carpet cleaner, and engine cleaner. Unfortunately, since it is environmentally persistent, it lingers in the air, water (e.g., in the military base Camp Lejeune), and soil across the US.
Bottom line: Outdoor air pollution also matters, not just the chemicals you are directly exposed to (e.g., in your job). TCE is a hazardous air pollutant, so avoid living (if you can) near a TCE emitting facility (especially in Lebanon, Oregon and Corydon, IN) because the risk of developing Parkinson's disease is the highest for people living near there.
From Science Daily: The invisible chemical in the air that could be raising Parkinson’s risk
Long-term exposure to the industrial solvent trichloroethylene (TCE) outdoors may be linked to an increased risk of Parkinson's disease, according to a large nationwide study published in the October 1, 2025, issue of Neurology, the medical journal of the American Academy of Neurology. ...continue reading "Commonly Used Chemical and Parkinson’s Disease"

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