ABSTRACT
A variety of pollutants is found in our environment. They arise from many sources, and exposure to them can occur through different routes. For example, in the ambient air in urban areas, SO2, CO, NOx, and smoke, suspended particles, lead (Pb), and hydrocarbons are produced largely from coal or heavy oil combustion by industries, power plants, and some households. A number of pollutants are also found in the indoor environment. Some examples are CO arising from incomplete combustion of fossil fuels and tobacco smoke, lead from paint used in old houses, and formaldehyde from insulation and wood preservatives and adhesives. In this chapter, where and how certain toxicants may occur in our environment are discussed. Also included in our discussion is a brief review of a number of pollution episodes or disasters that took place in recent decades.
