Development of a recommended exposure limit for a complex mixture - asphalt.
Sweeney-M; Wess-J; Zumwalde-R; Olsen-L
American Industrial Hygiene Conference and Exposition, May 10-15, 2003, Dallas, Texas. Fairfax, VA: American Industrial Hygiene Association, 2003 May; :70
The National Institute for Occupational Safety and Health (NIOSH) is updating its Recommended Exposure Limit (REL) of 5 mg/m3 (IS-minute ceiling) for asphalt fume, which is intended to prevent eye and respiratory irritation. Asphalt is a complex mixture of paraffinic and aromatic hydrocarbons and heterocyclic compounds. Some polyaromatic hydrocarbon (PAHs) constituents are classified as human carcinogens. The complexity of the mixture provides considerable challenge to the development of an occupational exposure limit. Nationwide, approximately 350,000 workers are involved in the application of asphalt paving or hot asphalt roofing materials, or the manufacture of roofing products. In 2000, the National Institute for Occupational Safety and Health (NIOSH) evaluated the scientific evidence concerning the potential health effects of occupational exposure to roofing and paving asphalts and asphalt-based paints. Although existing data are limited for quantifying acute and chronic health risks of asphalt exposure, they indicate that workers may be experiencing adverse acute health effects. Furthermore, NIOSH determined there was sufficient evidence to conclude that roofing asphalt fumes and asphalt-based paints should be considered potential occupational carcinogens. Subsequent to this determination, NIOSH performed additional analysis of health data to evaluate the relationship between exposure to asphalt fumes and acute respiratory symptoms. Because of the risk for cancer, several of the PAHs that comprise the complex mixture of chemicals found in asphalt fumes were also evaluated to determine the feasibility of developing PAH specific RELs. This presentation will describe: (1) data used to determine feasibility of developing a REL, (2) evaluation of an exposure-response relationship for acute health effects, and (3) research needed to evaluate risk for acute and chronic health effects from exposure to different types of asphalt fumes, and to better characterize and control fume exposures.
Exposure-limits; Asphalt-fumes; Eye-irritants; Respiratory-irritants; Hydrocarbons; Heterocyclic-compounds; Carcinogens; Occupational-exposure; Roofing-industry; Paints; Cancer
American Industrial Hygiene Conference and Exposition, May 10-15, 2003, Dallas, Texas