Some articles on pollutant, pollutants, primary:
... air that can cause harm to humans and the environment is known as an air pollutant ... Pollutants can be in the form of solid particles, liquid droplets, or gases ... Pollutants can be classified as primary or secondary ...
Famous quotes containing the word primary:
“Europe has a set of primary interests, which to us have none, or a very remote relation. Hence she must be engaged in frequent controversies, the causes of which are essentially foreign to our concerns. Hence, therefore, it must be unwise in us to implicate ourselves, by artificial ties, in the ordinary vicissitudes of her politics or the ordinary combinations and collisions of her friendships or enmities.”
—George Washington (17321799)