Agenda - 05-04-2004-7b - Laserfiche WebLink

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Overview of Air Quality in the Triangle: Outdoor air quality in the United States is regulated by the U.S, Environmental Protection Agency (EPA) under the authority of the federal Clean Air Act. The EPA sets National Ambient Air Quality Standazds (NAAQS) for six "criteria pollutants" that aze considered harmful to human health and the environment: cazbon monoxide, lead, ozone, nitrogen dioxide, particulate matter and sulfur dioxide. Particulate matter is fiuther classified into two categories: PM 10, or airborne particles with diameters of 10 micrometers or less, and PM 2.5, airborne particles with diameters of 2.5 micrometers or less, Levels of a pollutant above the health-based standazd pose a risk to human health. The North Carolina Division of Air Quality monitors levels of all six criteria pollutants in the Triangle region and reports these levels to the EPA. According to the most recent data, the Triangle region is meeting national ambient standards for five of the pollutants, but is not meeting the federal 8-hour standard for ground-level ozone. Therefore ozone is the pollutant of greatest concern in the Triangle at this time. Ozone-forming pollutants are volatile organize compounds (VOC) and nitrogen oxides (NOx). In the Triangle a lazge portion of VOCs is produced by natural sources, primarily trees. Major sources of man-made VOCS include unburned gasoline fumes evaporating from gas stations and cars, industrial emissions and consumer/industrial products such as paints and solvents. Nitrogen oxides aze produced when fuels aze burned, and result from the reaction of atmospheric nitrogen at the high temperatures produced by burning fuels. Major sources of NOx are highway motor vehicles, coal-fired power plants, and off-road vehicles such as construction equipment, lawn caze equipment, trains, airplanes and motorboats, North Carolina and the Triangle are considered to be Nox-limited, meaning that reducing NOx emissions is believed to be the most effective way to reduce ozone levels. Therefore, current ozone strategies focus on reducing NOx, Ozone Health Effects: When we breathe ozone, it irritates our lungs and respiratory passages. Long-term and repeated exposure to ozone concentrations above the NAAQS can result in reduction of lung function as the cells lining the lungs are damaged. Short-term, infrequent exposure to ozone can result in throat and eye imtation, difficulty drawing a deep breath, and coughing. Long-term and repeated exposure to ozone concentrations above the NAAQS can result in reduction of lung function as the cells lining the lungs ate damaged. Repeated cycles of damage and healing may result in scarring of lung tissue and permanently reduced lung function. Health studies have indicated that high ambient ozone concentrations may impair lung function growth in children, resulting in reduced lung function in adulthood. In adults, ozone exposure may accelerate the natural decline in lung function that occurs as part of the normal aging process. Ozone may also aggravate chronic lung diseases such as emphysema and bronchitis and reduce the immune system's ability to fight off bacterial infections in the respiratory system. Asthmatics and other individuals with respiratory disease are especially at risk from elevated ozone concentrations.