Health risks, put simply, are a measure of the chance that you will experience health problems. Exposure to toxic air pollutants can increase your health risks. For example, if you live near an industry that releases cancer-causing chemicals and inhale contaminated air, your risk of getting cancer may increase. Breathing air toxics could also increase your risk of non-cancer effects such as emphysema or reproductive disorders. The toxic air pollutants of greatest concern are those that cause serious health problems or affect many people.
Some health problems occur very soon after a person inhales a toxic air pollutant.
These immediate effects may be minor, such as watery eyes or coughing. Or they may be serious, such as life-threatening. Other health problems may not appear until many months or years after a person's first exposure to the toxic air pollutant, or only after prolonged or repeated exposure. Cancer is one example of a delayed health problem.