Air Pollution can be taken as a wide variety of problems. The first type is known as particulate matter. This is made up of aerosols that become suspended in the earth's atmosphere. These materials arise from the industrial processes and the burning of coal. Atmospheric particles can scatter and absorb sunlight which reduces visibility. Particles also reduce the visibility by fading the light from objects and illuminating the air causing the contrast between the objects and their backgrounds to reduce. Not only does it affect visibility, but it speeds up the erosion of buildings and the corrosion of metals, interferes with the respiratory system, and brings toxic chemicals into the body. The small particles cause chronic bronchitis, bronchial asthma, emphysema and lung cancer (Hodges 59). The second type is sulfur oxides which come from the industrial processes and the burning of coal. Damage to materials, vegetation, and the respiratory system are caused by the acid in oxides. Small quantities of sulfur can increase illness and mortality (Hodges 59). Oil with lower levels of sulfur have begun to be used to formulate gasoline that is used in today's cars. The third type of pollutant is carbon monoxide. Carbon monoxide is a colorless, odorless, tasteless gas against which humans have no protection. Carbon monoxide comes from the exhaust of gasoline powered vehicles and secondarily from industrial processes (Hamer 45). "The most polluting activity an average person does everyday is driving their car"(EPA). Hemoglobin, which is a chemical in the blood, gets affected by carbon monoxide, in turn, carries less oxygen to body tissues causing health and heart effects. Some health problems come from the exhaust fumes leaking into the interior of the automobile. "Several hundred Americans die from carbon monoxide poisoning each year (Hodges 60). The fourth type is chemical compounds known as hydrocarbons.