What air pollution does to your body and brain

Preterm birth and infant mortality rates rise in places where mothers are exposed to high levels of air pollution. Research presented in September indicates that when pregnant women breathe sooty air, pollution particles make their way into the placenta and may reach the baby.

Research conducted in California shows that reducing pollution levels in lower income schools would raise academic test scores in a small but significant way. Even indoor air quality has an effect — one study found that improving air quality in schools could significantly improve standardized test performance.

Research in the US shows that dementia and cognitive decline rates are higher in places with more air pollution, and these rates drop when air quality has been improved by enforcing EPA regulation. Research from China shows that the cognitive impairment associated with air pollution gets worse as people age, with a particularly strong effect on the verbal skills of less educated men.

Older adults are more likely to end up in the ER on days with high levels of air pollution, and kids are more likely to need medical treatment for asthma symptoms.

This is especially the case in places with high levels of pollution from cars.

As fires get worse, that number could top 40,000 per year by the end of the century, according to a study published in July.

Even short-term exposure to high levels of ozone, which is created when the sun heats up particles of pollutants, can increase rates for an irregular heartbeat. It also increases the risk for heart attacks, even for people without pre-existing heart disease.

Since the hot summer sun turns particles like those emitted from cars into ozone, air pollution makes the effects of heat waves — already deadlier than earthquakes and hurricanes — even worse.

One 2008 study found that for every degree Celsius the temperature rises, ozone pollution can be expected to kill an additional 22,000 people around the world via respiratory illness, asthma, and emphysema.

Approximately 5% of lung and throat cancer deaths can be attributed to air pollution.

On average, people lose about a year of life to air pollution, but this effect is much worse in some places than others. In China, bad air is associated with about a 3 year drop in life expectancy. In India, home to the 14 cities with the worst air pollution in the world, that's a 4 year drop.