Bitumen might be the first petroleum product used by man. List several uses early man found for bitumen. Nonbiodegradable - cannot be decomposed by microorganisms. Primary pollutants - emitted directly into the environment. Secondary pollutants - result from some action of a primary pollutant.
Acid rain is produced by the burning of fossil fuels that have a high sulfur content.
While any fossil fuel might have some sulfur, coal is the worst. Coal with a high sulfur content is much more common, therefore cheaper, than coal with a low sulfur content. The majority of the coal found in the northeast has a high sulfur content. It took years before the problem was recognized. Acid rain not only harms plants and animals, it also corrodes construction materials, such as metal and stone.