Stricter air limits on lead, ozone recommended

Science advisers are recommending that EPA tighten its air quality standards for lead and ground-level ozone. In late March, the agency's Clean Air Scientific Advisory Committee sent a letter to EPA Administrator Stephen L. Johnson saying the agency should not revoke the national limit for lead in air, as the Bush Administration is considering (C&EN, Jan. 8, page 39). Instead, the panel said, EPA should lower the current standard, set in 1978, of 1.5 µg/m³ of air for the neurotoxic metal to "about 0.2 µg/m³ or less." The agency is under court order to revise the air quality standard for lead by Sept. 1, 2008. In a separate letter, the advisory committee recommended that EPA ratchet down the current national air limit on ozone of 0.08 parts per million, set in 1997, to no more than 0.070 ppm, specified to the third decimal place. The agency is under court order to propose by June 20 whether it will keep or change the current ozone standard and to make a final decision on this air pollution limit by March 12, 2008.