When you think of factors that increase the risk of Alzheimer’s, dementia and Parkinson’s disease you probably think of genetics or traumatic brain injury. Even if you created a lengthy list of factors, you might never list air pollution—but more and more research shows that air pollution is involved in these brain diseases, which now affect 6 million Americans and 50 million people worldwide.
While we have known for years that air pollution increases the risk of asthma, lung infections and lung cancer, we are discovering that it is also linked to heart disease, depression, obesity and brain diseases. In a study published in the medical journal Environmental Health Perspectives, researchers assessed the effects of black carbon—a marker of traffic-related air pollution—on cognitive function and the central nervous systems of male study participants. The scientists found that there was a significant link between air pollution levels and a reduction in cognitive function, a worrisome result given our growing air pollution emissions.