Particles containing lead in the air can enter the lungs. The lead can then be absorbed into the blood stream. Over a period lead can affect the nervous system and the body's ability to produce blood. Particles Motor vehicles, burning of plant materials, bushfires. May cause breathing difficulties and worsen respiratory diseases.
Some particles contain cancer-producing materials.
In addition to ozone, photochemical smog contains a number of other harmful secondary pollutants such as peroxyacetyl nitrate and aldehydes, which are severe irritants, particularly to the eyes. Air quality indoors Australians on average spend about ninety-five percent of their time indoors and many pollutants occur at higher concentrations indoors than outdoors because of the materials and appliances used in buildings. Many people's main exposure to air pollutants occurs when they are indoors, such as at home, in the workplace or in entertainment venues. Researchers are working towards measuring 'individual exposure' to pollutants. That is, a measure of the actual exposure that people have to air pollutants during their daily routines, rather than measures of pollution at fixed locations.