Controversy besets EPA standard for small particulates

EPA's new air quality standard for fine particulate matter, defined as particles with a diameter of 2.5 µm or less, is generating plenty of controversy. The agency on Sept. 21 retained the existing standard that permits a yearly average for fine particulate matter of 15 µg/m³ of air. EPA also lowered the daily maximum allowable amount of fine particulates to 35 µg/m³ of air, ratcheting down from the 65 µg/m³ standard set in 1997. Health and environmental groups called the new fine particle limits insufficient for protecting the public from adverse cardiovascular effects from breathing in fine particulates. They also blasted the agency for ignoring its science advisers, who recommended that EPA lower the annual standard to between 13 and 14 µg/m³. Business groups, including the American Chemistry Council, opposed a lowering of the daily allowable standard. ACC said EPA's actions will drive up energy prices. Sources of fine particulates include power plants, industrial processes, vehicle exhaust, and forest fires.