Biological Monitoring of Employees with Potential Exposures to Inorganic Lead and Cadmium at Municipal Solid Waste Resource Recovery, or Trash-to-Energy, Facilities

Abstract

Resource recovery (trash-to-energy) facilities reduce the volume of municipal solid waste through incineration, while generating steam for the production of electrical power. The noncombustible, dustlike ash residue produced by these plants is composed of inorganic constituents and metal contaminants which are concentrated from the original trash, including inorganic lead and cadmium. Handling and working around the ash has the potential to cause worker exposures to these metals. This ash is ultimately disposed of in appropriately designed and permitted landfills. Although overall lead and cadmium exposures to workers in the industry are generally quite low, a small number of dusty jobs such as ash handlers have resulted in exposures that exceed the Occupational Safety and Health Administration permissible exposure limit for lead. Personal protective equipment (PPE), and in particular personal respiratory protection (air-purifying respirators with high efficiency particulate air filtration), and appropriate hygienic work practices (protective clothing, showers and hand washing, and lunchroom facilities) are used by workers to control potential exposures to airborne lead and cadmium. Biological monitoring of the work force confirms that the PPE and hygienic work practices programs are effective in controlling worker exposures to lead and cadmium.