Nonferrous metallurgical slag (copper slag) is commonly used as a substitute for silica sand due to potential health hazards of crystalline silica (silicosis and lung cancer), and in roofing products and other aggregate uses. Even though copper slag is thought to be less toxic than silica sand it contains potentially toxic metals such as arsenic, beryllium, and lead. Study objectives were to quantify personal breathing zone exposures for comparison to OSHA exposure limits; model relationships between respirable dust and crystalline silica, and total dust and metal aerosols; and determine whether releasable metal contamination on hands, clothing, and/or contact surfaces is a contributing exposure pathway. Personal breathing zone samples for arsenic exceeded OSHA Action Level and Permissible Exposure Limit in 30% and 3 % of samples; lead, beryllium, and respirable crystalline silica samples were consistently below the Action Level. Linear regression analysis demonstrated good correlation between area air levels of respirable particulate and crystalline silica (R2 = 0.909); moderate correlation between area concentrations of total particulate and arsenic (R2 = 0.791) and lead (R2 = 0.786); and weak correlation with beryllium (R2 = 0.208). Releasable arsenic and lead were consistently present in hand, clothing, and building surface wipe samples; beryllium was consistently below limit of detection. Data demonstrate an increased risk of employees ingesting metal particles by direct hand-to-mouth contact, as well as from particles that dislodge from their clothing directly onto food and/or food eating surfaces. Operating mobile equipment with doors closed effectively reduced operator’s exposure levels. Operating vibratory screens with covers and local exhaust ventilation reduced fugitive particulate levels in the Screen House. Recommendations to reduce exposures are offered based on Hierarchy of Controls. Study results assist other professionals to make a more informed determination of health risk posed to workers at similar copper slag processing facilities.
