We have no choice but to breathe the air around us.
But the machines we use and policies that governments enact transform that air. Cars fill the air with the exhaust they pipe out, factories and power plants belch residue into the sky, and city apartment buildings pump out chemicals they use to heat and cool residences. In many places, trees that could help improve air quality have disappeared.
All of this has effects on human health, and some of these effects can be scary.
Bad air does more than just making it harder to breathe. It can change the way children’s brains develop and make older adults more likely to succumb to cognitive decline.
This is an urgent, global problem – 98% of cities with populations over 100,000 in low- and middle-income countries don’t meet the World Health Organisation (WHO) air quality standards.
Even in the US, with relatively high standards for air quality, there’s evidence that people are breathing air that has a negative effect on their bodies and brains.
Here’s what air pollution does to your health, and why you should pay attention to the quality of the air around you.
Kids who are exposed to poor air early in life are more likely to develop asthma and struggle in school, and there are indications this early-life exposure may harm cognitive development.
Studies conducted in China and Canada show that kids who breathe poor air are more likely to have breathing difficulties and asthma. Research conducted on New York City schoolchildren shows that ones who breathe poor air are more likely to need academic intervention.
There are strong indications that air pollution affects kids before they are born if their pregnant mothers breathe polluted air.
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.
Kids who breathe poor air do worse on academic tests.
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 standardised test performance.
And these cognitive effects continue to build up throughout life, with elderly people who breathe bad air more likely to suffer from dementia and Alzheimer’s.
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.
There’s lots of data showing that poor air quality increases asthma and lung disease rates.
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.
There are also indications that people exposed to higher levels of air pollution are more likely to develop allergies.
This is especially the case in places with high levels of pollution from cars.
Air pollution from wildfire smoke kills around 15,000 people per year in the US, through heart disease, lung disease, asthma, and other respiratory problems.
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.
Exposure to ozone pollution increases the rates of cardiovascular disease, including heart attacks.
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.
Air pollution makes the health effects of heat waves far worse.
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.
Air pollution raises lung cancer rates.
Approximately 5% of lung and throat cancer deaths can be attributed to air pollution.
Air pollution has significant effects on life expectancy, especially in developing nations.
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.
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