September 25, 2026

@michaelokun

Air pollution and Parkinson’s disease is a connection we can no longer afford to ignore. This new nationwide study of more than 5.3 million older adults in South Korea, including more than 143,000 people who developed Parkinson’s, found that long-term exposure to PM2.5 fine particulate pollution and ozone was associated with a small but statistically significant increase in Parkinson’s incidence. The effect for any one person was modest, and this observational study cannot prove that pollution causes Parkinson’s, but when an exposure affects millions of people, even a small increase in risk can become important at the population level. There is also biological plausibility: fine particles may reach the brain through the circulation or olfactory (smell) pathways and potentially contribute to oxidative stress, microglial activation, neuroinflammation, abnormal protein handling and injury to vulnerable dopamine neurons. For me, the message is not fear; it is prevention. We need cleaner air and better research, but we should also be thinking about practical ways to reduce our individual exposures while the science continues to evolve. Do you have a HEPA air filter in your home, and do you wear a mask outside on polluted days? https://movementdisorders.onlinelibrary.wiley.com/doi/10.1002/mds.70518