Breathing in polluted air could mean shortening your life, new research finds.
Researchers from the United States, Canada, and the United Kingdom studied the average human life expectancy worldwide and how air pollution influences the length of someone's life. Published in Environmental Science & Technology on Wednesday, the study revealed that air pollution could reduce lives by years, depending on where they live.
The scientists used the 2016 country data from the Global Burden of Disease project. The study is the first to look at life expectancy impacts in specific countries from pollution called fine particulate matter. Fine particulate matter are small pieces of pollution that are smaller than 2.5 micrometers—30 times smaller than the width of a piece of human hair. Air pollution can severely impact someone's health.
For example, a recent study found that air pollution, even in minimal amounts, can change the structure of someone's heart to mimic early stage heart failure. The scientists had the goal to help non-scientists understand the consequences of air pollution.
"Talking about mortality figures and large body counts, you see people's eyes glaze over," Joshua Apte, an environmental scientist at the University of Texas at Austin and author on the paper, told Science News. "People care not just about whether you die—we all die—but also how much younger are you going to be when that happens."
Every population has a different baseline health level, so the impact on mortality from air pollution varies between each country. In the United States, air pollution could remove 0.38 years from someone's life. In countries with higher levels of air pollution, such as Bangladesh, 1.87 years could be taken from citizens' lives.
The country with the lowest impact from air pollution on their mortality was Sweden. In Sweden, air pollution could shorten lives by 0.13 years. Also, low on the list are New Zealand (0.16 years), Australia (0.18 years) and Kiribati (0.21 years). After Bangladesh, the countries with the highest effect on life expectancy are Egypt (1.87 years), Niger (1.8 years) and Tajikistan (1.7 years). The study found that a total of 42 countries saw their life expectancy decreased by a year or more due to air pollution.

The scientists also studied how reducing the amount of air pollution by 10 micrograms per cubic meter of air could benefit people in each country. The 10 micrograms per cubic meter of air recommendation is from the World Health Organization. Many countries already meet this standard, including Canada and the United States, however, the change could help countries whose pollution levels are far above that.
For example, if Niger were to meet that standard, people in that country could gain back 1.45 years of life on average. In China, people could gain back .76 years of life. Despite that goal, 10 micrograms per cubic meter of air doesn't mean the air is pristine—even people in countries who have already met that goal still face negative effects from the pollution in the air.