Particulate matter-Particulates,alternatively referred to as particulate matter or fine particles,are tiny particles of solid or liquid suspended in a gas. In contrast,aerosol refers to particles and the gas together.from volcanoes, dust storms,forest and grassland fires,living vegetation,and sea spray. Human activities,such as the burning of fossil fuels in vehicles,power plants and various industrial processes also generate significant amounts of aerosols. Averaged over the globe,anthropogenic aerosols-those made by human activities -currently account for about 10 percent of the total amount of aerosols in our atmoshere. Increased levels of fine particles in the air are linked to health hazards such as heart disease,altered lung function and lung cancer