A new report by the National Institute for Occupational Safety and Health (NIOSH) reviews current scientific data on health effects related to occupational exposures to asphalt, describes further research needs in this area, and suggests measures to minimize worker exposures while studies continue.
The report, "Hazard Review: Health Effects of Occupational Exposure to Asphalt," is part of NIOSH''s ongoing work to explore the complex questions pertaining to job-related asphalt exposure and health effects.
NIOSH said current research findings support a previous assessment from 1977 that exposure to asphalt fumes is associated with eye, nose and throat irritation.
Recent studies also have found evidence of lower respiratory tract symptoms among workers exposed to asphalt fumes.
The report discusses studies that associate asphalt exposure with potential long-term health effects, such as chronic bronchitis and lung cancer.
The report reviews data from those studies that relate to potential long-term effects under different conditions of use, including exposures from paving, roofing and asphalt-based paint formulations.
NIOSH concluded that additional studies are needed to better characterize occupational exposures to asphalt fumes, vapors and aerosols, and to further evaluate the risk of chronic disease, including lung cancer.
In the meantime, NIOSH recommends that possible health effects from the exposures to asphalt, asphalt fumes and vapors, and asphalt-based paints be minimized.
Exposures can be minimized, the report suggests, by adhering to NIOSH''s current recommended exposure limit of 5 milligrams of asphalt per cubic meter of air over any 15-minute period, and by:
- preventing skin exposure;
- keeping the application temperature of heated asphalt as low as possible;
- using engineering controls and good work practices at all work sites to minimize worker exposure to asphalt fumes and asphalt-based paint aerosols; and
- using appropriate respiratory protection for workers.
by Virginia Sutcliffe