The Health of our Air Document in PDF Format Please direct all questions and comments to Barry Grace Background Globally, agriculture is the main source of atmospheric NH 3 from human activity. Much of this NH 3 comes from livestock production. In parts of Europe, notably the Netherlands, NH 3 emissions from animal production are so high that they warrant strict regulations. In Canada, the problem is not yet as acute, except perhaps in local areas with high livestock numbers.
Ammonia is a colorless gas, lighter than air, with a sharp odor.
As well, NH 3 can react with pollutants such as acidic sulfates and nitrates, forming tiny particles of ammonium nitrate or ammonium sulfate. In an area near Lethbridge, Alta., for example, high concentrations were found close to feedlots, but relatively low values just 1 km away. Ammonia has many undesirable effects at high concentrations. Near sources, where concentrations are high, it produces an unpleasant odor and may affect human and animal health. Excessive NH 3 may even be converted to N 2 O, thus indirectly contributing to the greenhouse effect.