EPA Tightens Some Air Regulations.

This article reports that the U.S. Environmental Protection Agency proposed new rules that would cut almost in half the maximum amount of fine particulates that people should breathe over 24 hours. However, the agency did not reduce the average annual amount allowed, rejecting the advice of its own scientists and its scientific advisory panel. Many studies have shown that the inhalation of small particles can harm health and even lead to the premature death of people suffering from lung and heart disease. The agency proposes lowering the standard for 24-hour exposure for PM 2.5 from 65 micrograms per cubic meter. Lung Chi Chen of the New York University School of Medicine in New York City and his colleagues exposed heart disease-prone mice to polluted air.