Primary pollutants are those in which the substance emitted is itself hazardous. Some primary pollutants also produce other dangerous substances after undergoing chemical reactions in the atmosphere, and these are known as secondary pollutants. Primary pollutants include the following substances. Particulates This includes dust, smoke, aerosols and haze - any finely divided airborne solid material. Particulates are commonly generated by fires, motor vehicles, some industries (particularly road building, quarries and fossil fuel power stations) and various natural sources including volcanoes, plant and animal matter and dirt. Particulates are aesthetically displeasing, can irritate the eyes and.
