A pollutant is a substance that harms the environment or makes it unhealthy. Pollution often comes from things we use and throw away.
When people talk about pollutants, they usually mean chemicals, gases, or waste that contaminate air, water, or soil. For example, when a company dumps toxic waste in a river, that's a pollutant. Or if someone smokes near a park where kids play, the secondhand smoke is also a pollutant. Even some household items can be pollutants if they're not disposed of properly – like batteries or old paint. Scientists and governments often work together to identify and reduce pollutants in our environment.
A foreign substance that makes something dirty, or impure, especially waste from human activities.
