Apart from increasing the risk of respiratory problems and other life-threatening conditions, a recent study has found that air pollution may also be a threat to your kidneys.
A University of Michigan study has highlighted the lesser-known connection.
"Similar to smoking, air pollution contains harmful toxins that can directly affect the kidneys," said Jennifer Bragg-Gresham, the study's lead author.
"Kidneys have a large volume of blood flowing through them, and if anything harms the circulatory system, the kidneys will be the first to sense those effects."
People with diabetes, obesity, high blood pressure or heart disease are at increased risk of developing chronic kidney disease (CKD). Which is why high-risk patients who live in heavily populated or polluted areas should recognise the danger and take precautions, Bragg-Gresham said.
The study's co-author, Rajiv Saran, a Michigan Medicine nephrologist, said, "If you look at areas that are heavily polluted versus areas that are less polluted, you will find more chronic kidney disease."
People with CKD have an eightfold increased risk of cardiovascular mortality.
"What this means for the countries with a higher particulate matter, or PM2.5, is significantly higher odds of CKD," said Bragg-Gresham.
"In heavily polluted areas, consider wearing masks that cover your nose and mouth, limit hours outside and limit long hours commuting to work in high traffic as well," Saran said, adding that the risk should be taken seriously.
"Many people don't see the seriousness of air pollution because it isn't something visible, but that doesn't mean it's any less important for your health."
The study has been published in the journal PLOS ONE.