Not a day seems to go by without a story of an “airpocalypse,” usually somewhere in a developing nation. It’s hard not to empathize with the people in the smoggy images of New Delhi or Ulaanbataar or Kathmandu, often wearing masks, walking to school or work though soupy cloudiness.
Last year, a study found that more than 8 million people per year die early from air pollution exposure. This amounts to more deaths than diarrheal disease, tuberculosis and HIV/AIDS combined.
As a researcher in air pollution and its health effects, I know that even if you don’t live in these places, air pollution likely still affects your quality of life. Here’s what you need to know.
1. What exactly is air pollution?
Air pollution is a general term that usually describes a mixture of different chemicals that circulate in the air.
Invisible gases, like ozone or carbon monoxide, and tiny particles or droplets of liquids mix together in the atmosphere. Each molecule is impossible to see with the naked eye, but when trillions gather together, you can see them as haze.
These chemicals are almost always mixed together in varied amounts. Scientists do not yet understand how these different mixtures affect us. Each person responds differently to air pollution exposure – some people have few effects, while others, such as kids with asthma, might become very ill.
What’s more, air pollution mixtures in a given location change over time. Changes can occur quickly over a few hours or gradually over months.
Air pollution from day to day
This graph of air pollution (pm25) in Ulanbaatar shows how the level of pollutants in the air can fluctuate from day to day.