A new study has found that long-term exposure to a chemical called trichloroethylene (TCE), often used in factories and dry cleaning, may be linked to a higher risk of Parkinson’s disease.
Parkinson’s is a brain disorder that affects movement, often causing tremors, stiffness, and problems with balance and coordination.
The disease develops slowly over time and has no cure. It mostly affects people over the age of 60.
TCE is a powerful chemical that helps clean metals, remove grease, and is sometimes used in making other products. While some of its uses have been banned in the U.S., it’s still used in some industrial settings.
The problem is, TCE doesn’t just disappear after it’s used. It can stay in the air, water, and soil for a long time, making it a concern for the environment and public health.
Researchers wanted to see if people living in areas with high levels of TCE in the air were more likely to get Parkinson’s disease. To do this, they looked at health records from Medicare, focusing on people aged 67 and older who were diagnosed with Parkinson’s between 2016 and 2018.
For every person with Parkinson’s, they compared five other people who didn’t have the disease. In total, they studied over 1.3 million people.
The team checked how much TCE was in the air in different neighborhoods using data from the U.S. Environmental Protection Agency. They grouped people based on the estimated TCE levels in their area two years before the Parkinson’s diagnosis. Some people lived in areas with very low levels of TCE, while others were in places with much higher levels.
After adjusting for other things that can affect Parkinson’s risk, like age and whether someone smoked, the researchers found that people who lived in areas with the highest TCE levels had a 10% higher chance of getting Parkinson’s compared to those in the cleanest areas.
That may not sound like much, but since millions of people may be exposed to this chemical, even a small increase in risk could affect many lives.
The study also found that some parts of the country had especially high levels of TCE in the air. These “hot spots” were often in industrial areas, including places in the Midwest’s Rust Belt.
They also looked closely at three of the largest TCE-emitting factories in the U.S. and found that people living closer to these facilities had a higher risk of Parkinson’s, especially when the pollution levels were highest.
It’s important to note that this study doesn’t prove TCE causes Parkinson’s. It only shows that there may be a link. More research is needed to understand exactly how the chemical might affect the brain.
Also, the study mostly looked at older adults, so we don’t know if younger people are affected in the same way. And because they used data from 2002 to estimate TCE levels, it’s possible that people’s exposure has changed since then.
Still, this study adds to growing concerns that pollution and chemicals in our environment could play a bigger role in diseases like Parkinson’s than we previously thought. The researchers say that we may need stronger rules to control chemicals like TCE and better systems to monitor air quality in neighborhoods.
The study is published in Neurology.
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