If you add the valences of each atom in the molecular formula for arsenious acid, H 3 AsO 3, you can see that the molecule, which is uncharged, has a total valence state of 0 (3x(+1) for the hydrogen atoms; 1x(+3) for the arsenic(III) atom; 3x(-2) for the oxygen atoms = 3+3-6 = 0).
Eighty percent of sewage in India is untreated and flows directly into the nation's rivers, polluting the main sources of drinking water, a study by an environment watchdog showed Tuesday.
Industrial water and water pollution. Industry is a huge source of water pollution, it produces pollutants that are extremely harmful to people and the environment. 1  Many industrial facilities use freshwater to carry away waste from the plant and into rivers, lakes and oceans. 2  Pollutants from industrial sources include: