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Air Pollution May Make Your Brain Age Faster, Study Says

2 minute read

Long-term exposure to air pollution may cause your brain to age more quickly and put you at higher risk for a stroke, a new study suggests.

Exposure to higher levels of air pollution may be linked to lower total cerebral brain volume, according to a study published in the May issue of Stroke, which analyzed health data from nearly 1,000 men and women over 60 who did not have dementia and had not had a stroke.

Total cerebral brain volume naturally decreases as humans age, resulting in declines in ability to learn new things and retrieve information, but the researchers found that air pollution exposure may be linked to premature brain aging and higher risks for certain brain strokes.

The findings add new knowledge to the impact of air pollution on the structure of the brain, a link that has remained largely unclear in research.

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Bakersfield California Air Pollution Climate Change
A passenger train travels through town past a refinery in Bakersfield, Calif.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Oil pumps and scarred earth can be seen for miles in an area of North Bakersfield called the Bluffs. A Cogeneration Plant sits in the middle of the fields and is one of California's top polluters.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
A dust storm blows through Bakersfield, Calif. Dust is a pervasive problem in the area.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Yareli Gonzalez, 7, suffers from asthma and receives two nebulizer treatments per day, indefinitely. Gonzalez lives in Shafter, a rural farming town in Kern County, Calif. Kern County sits at the southern end of the San Joaquin Valley, an area known for having the worst air in the nation due to dust, smog and high levels of ozone.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Asthma educator Sharon Borradori, left, shows Margarita Hernandez, center, and her husband, Severo Velasco, right, how their 2-year-old son, Mauricio Velasco will use an inhaler when he's older. Mauricio was recently released from the hospital after suffering from an extreme asthma attack. Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Children practice sports on a field at Bakersfield High School which backs up against the train yard that runs through the middle of town in Bakersfield.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Young football players exercise on the stadium of Bakersfield High School. Bakersfield High is the oldest high school in town and the mascot, the Driller, is directly tied to area industry.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Benjamin Swall, 14, waits for his brother's football practice to end at Bakersfield High School.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Red Simspon, a country music legend and Bakersfield native, smokes a cigarette outside of the Rasmussen Senior Center in Oildale, north of Bakersfield. Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Merced Mendoza moves irrigation pipe in a field that will be used to grow alfalfa. The field is adjacent to and owned by Kern Oil and Refining Co. Mendoza is a leader for a men's group at Victory Outreach Church in Bakersfield that rents the land from the refinery to grow alfalfa that is then sold to a local dairy for feed. The money earned from the feed helps fund the men's program for the church. This symbiotic relationship between resource companies and the community are played out throughout the region.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Percolation ponds fill up with runoff water from nearby Belridge Oil Fields in Eastern Kern County. As the water evaporates, leaving oil residue, hydrogen sulfide, methane and volatile organic compounds, or VOCs, are released in to the air.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Dust devils can be seen reaching toward the sky during dry months in Bakersfield. Dust is a pervasive problem that contributes to diminished air quality. The problem is exacerbated by the current drought in California.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Lucy Clark, 72, lives in the foothills north of Bakersfield. Her home sits at 2200 feet, which is about the elevation where the visible layer of smog begins to hang in the air. Because of this, Clark, who suffers from asthma, wears a mask every day she walks out to get the mail.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Elk Hills Power plant provides electricity to power Occidental Elk Hills oil field. Oxy's Elk Hills field is one of the largest oil fields in the United States and the natural gas power plant can produce 550 megawatts of electricity.Lexey Swall—GRAIN
Bakersfield California Air Pollution Climate Change
Samantha Olivarez, 9, left, and her cousin, Daisy Olivarez, 7, play in front of their home in Arvin, Calif. The homes across the street were evacuated after a gas pipe leaked underground. According to reports, the 40-year-old pipe was leaking for as long as two years before it was detected. Olivarez's family is worried about possible health risks in the area due to the pollution.Lexey Swall—GRAIN

Specifically, a 2 microgram per square meter increase in PM2.5 (particulate matter in the air that is less than 2.5 micrometers wide) was associated with a 0.32% lower total cerebral brain volume, the study said. To put that in context, brain volume decreases at about 0.5% per year after age 40, and PM2.5 levels can vary widely across the world. For example, the PM2.5 in Beijing is about 175 micrograms per square meter, while the PM2.5 in New York City is about 30 micrograms per square meter.

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