Scientific evidence shows that breathing polluted air can impair memory and reasoning, reduce academic performance and even lower intelligence. Here are three important examples of how air quality directly affects cognitive functioning:
1. Performance on standardized tests
Standardized tests have become increasingly important in education. Parents and educators already debate the potential impact of family income, cultural background, gender and other influences on test results. Now researchers are also looking closely at the impact of air quality on standardized test scores – and concluding that the impact is significant.
Multiple studies have identified a link between air quality and performance on standardized tests. For example, one study of school children in Southern California found that exposure to higher levels of fine particulate air pollution (known as PM2.5) is linked to consistently lower scores on standardized tests in math and reading. A separate study of fifth-grade school children concluded that every increase of 2.1 cubic feet per minute (cfm) in ventilation was associated with a 2.9% increase in students passing a standardized math test.
2. Cognitive skills and aging
Evidence is growing that cognitive decline associated with aging is at least partially related to breathing air pollution. In one study, scientists administered math and memory tests to 780 people age 55 or older, then correlated scores with pollution levels where the participants lived3. After adjusting the results for education, employment and other factors, the researchers still found significant differences in scores based on air quality. Participants in areas with high pollution levels had error scores that were 150% higher than those living in areas with low pollution.
Scientists are gradually identifying the connection between air pollution and the brain. Neuroscience researchers exposed mice to high levels of particulate air pollution (similar to levels in Beijing or Mexico City) for a 10-month period4. They observed that the mice exposed to high pollution levels took longer to navigate through a maze and made more mistakes.
Examining the brains of the mice exposed to pollution, the researchers found physical changes in the tips of neurons in the part of the brain responsible for memory. The researchers also found that the mice exposed to high levels of pollution showed increased levels of pro-inflammatory chemicals in the brain.
What you can do
We can each play an important role by taking action to clean the air we breathe indoors and outdoors. We can help reduce the sources of pollution, better ventilate our indoor environments and provide air filtration for schools and other indoor environments as needed. Here are a few examples of the positive steps we can each take to clean the air:
- Get involved: Schools with better indoor air quality have better attendance rates and test scores. If air quality is an issue in your local schools, ask your school principal, school board members or local chapter of the American Lung Association what you can do to get involved in improving classroom air quality.
- Avoid unnecessary exposure: Avoid unnecessary exposure to outdoor air pollution and use a high-performance air purifier such as the IQAir HealthPro Plus to keep the air clean at home. For ranking of the best and worst regions of the nation in terms of air pollution, and to check pollution levels where you live, visit www.stateoftheair.org.
- Reduce air pollution: Conserving energy, recycling, driving less or driving low-polluting vehicles — the choices you make can help reduce air pollution for everyone. Visit the U.S. Environmental Protection Agency website (www.epa.org) for more ideas.
To learn more about the connection between Indoor Air Quality and your health, visit the American Lung Association at www.lung.org.