Air pollution linked to cognitive decline
The fine particulate matter from vehicle exhaust and other sources of air pollution may speed up the loss of cognitive skills in older adults.
For the study, researchers gathered information from one aspect of a large, ongoing survey started in 1986. They focused on 780 participants who were 55 or older at the time of the 2001/2002 survey. Cognitive function was measured by math and memory tests, and air pollution levels were measured in each participant’s neighborhood using the particulate levels reported by the U.S. EPA’s Air Quality System. Previous research has shown that pollution particles 2.5 microns or smaller can go deep into the lungs and enter the bloodstream.
Results showed that the average pollution levels in the study participants’ environments were 13.8 micrograms per cubic meter, which exceeds the EPA’s standard 12 micrograms per cubic meter. They also found that people living in high pollution areas (15 micrograms per cubic meter), performed more poorly on the cognitive tests than those people who lived in low pollution areas (no more than five micrograms per cubic meter).
The scientists say they think the particulate matter affects cognitive function in older adults because of its impact on the cardiovascular system, which feeds blood to the brain.