Air pollution has long been recognized as a contributor to the increased risk of heart and lung ailments, especially in the developing bodies of young children. But air pollution may be just as detrimental for aging brains, according to data presented at the Gerontological Society of America’s 65th Annual Scientific Meeting last week in San Diego.
The study, conducted by researchers at the University of Southern California-Davis (USC-Davis), included 14,793 seniors age 50 or older who were given various memory and other cognitive tests. The cognitive data was then compared to air particle data collected by the Environmental Protection Agency. Areas with the highest fine-particle air pollution saw the greatest declines in cognitive skills. The longer the exposure, the lower the test scores.
"The study shows the unexpectedly adverse effects of air pollutants on brain function in the elderly," Caleb Finch, professor in the neurobiology of aging at the USC-Davis and one of the researchers, said in a statement.
Fine particle pollution, also known as soot, can easily become embedded deep in the lungs. Some particles are so small they can pass right through lung tissue and into the blood stream, where they may possibly find their way to the brain, researchers noted.
When the dirtiest cities were compared with the cleanest, the areas with the highest air pollutants correlated to a three-fold drop in thinking skills and memory, the study noted.
On the American Lung Association’s 2012 State of the Air list of the Top 25 dirtiest places for year-round particle pollution (soot), the top five cities are in Southern California. Other areas in the top 10 include Pittsburgh; Phoenix; Cinncinnati, Ohio; Louisville, Ky.; and Philadelphia. The good news: Many U.S. cities are experiencing their cleanest air in the past 13 years, the 2012 report says.