Fine Particulate Levels in U.S. Are Dropping

Levels of fine particulate matter dropped 10% between 1999, when monitoring of this pollutant began, and 2003, EPA says in a report released on Dec. 14. The agency attributed the reduction of these particles, with sizes of 2.5 µm or less, to its program to control acid rain. These fine particles are associated with a variety of health problems, from chronic bronchitis to heart arrhythmia. Concentrations of fine particulate matter have fallen across the U.S., EPA says, with locales having the highest levels of particulates experiencing the steepest decline. However, it says that "millions of people still live in areas of the country where particle pollution exceed[s] levels established to protect public health." The report is available at http://www.epa.gov/airtrends/pm.html.