Air is frequently contaminated.
air pollution, when an individual breathe in too much contaminated air it may lead to Asthma
it can get contaminated by passing thought traits that are already contaminated
I think it depends how badly they were contaminated, but if you let them air for a day or two they should be fine.
Refrigerant contaminated with air won't function properly.
The homeowners had their water tested for contaminants before drinking from the faucet.
The environment (soils, air, waters) was contaminated.
House flies