Nature and Sources of the Pollutant:
Particulate matter less than 10µm in size (PM10) is a small fraction of the suspension sized material that may cause health problems when inhaled and other environmental problems. Stringent Federal air quality standards regulate concentrations of PM10 as a health hazard. Wind erosion has been linked to increased particulate matter emissions from agricultural fields as well as other sources such as sand dunes, unpaved roads, construction and mining sites, dry lake beds, rangelands, and forest lands.
Health and Environmental Effects: In 1987, EPA replaced the earlier Total Suspended Particulate (TSP) air quality standard with a PM-10 standard. The new standard focuses on smaller particles that are likely responsible for adverse health effects because of their ability to reach the lower regions of the respiratory tract. The PM-10 standard includes particles with a diameter of 10 micrometers or less (0.0004 inches or one-seventh the width of a human hair). EPA's health-based national air quality standard for PM-10 is 50 µg/m3 (measured as an annual mean) and 150 µg/m3 (measured as a daily concentration). Major concerns for human health from exposure to PM-10 include: effects on breathing and respiratory systems, damage to lung tissue, cancer, and premature death. The elderly, children, and people with chronic lung disease, influenza, or asthma, are especially sensitive to the effects of particulate matter. Acidic PM-10 can also damage human-made materials and is a major cause of reduced visibility in many parts of the U.S. New scientific studies suggest that fine particles (smaller than 2.5 micrometers in diameter) may cause serious adverse health effects. As a result, EPA is considering setting a new standard for PM-2.5. In addition, EPA is reviewing whether revisions to the current PM-10 standards are warranted.