Fine airborne particles are primarily emitted from fuel-burning vehicles. Diesel engines are particular culprits, emitting soot and unburned hydrocarbons. Statistics from London indicate that "diesels installed in buses, lorries and taxis produce 85% of the smoke for which transport is responsible, which is itself 95% of the total - 18,600 tonnes in 1993. Newer designs tend to be cleaner, but many urban vehicles have working lives of 30 years. Ways need to be found to deal with these older vehicles." (The Economist, February 18, 1995 p. 83).
Studies reported in 1995 issues of the American Journal of Epidemiology, the Lancet, and the American Journal of Respiratory and Critical Care Medicine all link specific cardiac illnesses to fine particulate air pollution. In addition, increased levels of other types of air pollution, such as carbon monoxide and sulfate particulates, have also been linked to increases in heart failure and lung diseases.
These findings should strengthen the public demand and political will to require catalytic converters and filters, to produce clearer burning engines, and to reduce or restrict vehicle traffic, particularly in areas of high population density. In addition, those who walk or bicycle now have additional reasons to encourage the enforcement of clean air standards for a variety of pollutants, including the fine particulates.
Sources of information for this article: "Airborne Particles: Smallest are Worst", Acid News 3, June 1995, page 5; "Heart-y Risks from Breathing Fine Dust", Science News Vol. 148, July 1, 1995, page 5; "Air Pollution: The Way to Dusty Death", The Economist, February 18, 1995, pages 82 - 83.