Link between CLEAN air and brain health
Cars and factories produce a fine particulate known as PM2.5 that the studies have linked to memory loss and Alzheimer’s disease. These particles are smaller than the width of human hair, but they can be big trouble. Once inhaled, they pass directly from the nose up and into the brain, beyond the blood-brain barrier that normally protects the brain from dust or other invaders.
The USC researchers described how their labs each independently reported indications of recent decreases in neurotoxicity (damage to the brain or nervous system caused by exposure to toxic substances) of PM2.5 air pollution in humans and mice.
University Professor Caleb Finch and associate professor of gerontology and sociology Jennifer Ailshire, both with the USC Leonard Davis School of Gerontology, focused on PM2.5 pollution. Long-term exposure to PM2.5 has been linked to premature death, particularly in people with chronic heart or lung diseases.
Ailshire’s research was published earlier this year in the ‘Journal of Alzheimer’s Disease’. It established an association between cognitive deficits and air pollution among people with lower levels of education in 2004. But one decade later, Ailshire found no such association for study participants, suggesting that the improvements with cognitive decline were linked to a drop in exposure to high pollution among older adults.
“Improving air quality around the country has been a tremendous public health and environment policy success story. But there are signs of a reversal in these trends,” Ailshire said.
“Pollution levels are creeping up again and there are increasingly more large fires, which generate a significant amount of air pollution in certain parts of the country. This gives me cause for concern about future trends in improving air quality,” Ailshire added.
Finch’s research on mice, published earlier this year in the ‘Journal of Alzheimer’s Disease’, also found evidence of lower neurotoxicity of air pollution over time.
Over time, the composition of air pollution in the United States was also changing.
“Our findings underscore the importance of efforts to improve air quality as well as the continued importance of demographic and experimental evaluation of air pollution neurotoxicity,” Finch said.