Measurement of Multiple Inorganic Arsenic Species

Abstract

While multiple species of inorganic arsenic can coexist in industrial environments, traditional air sampling methods and analysis by atomic absorption spectrometry quantify only total inorganic arsenic. The National Institute for Occupational Safety and Health (NIOSH) recently conducted laboratory experiments and field studies to develop a technique to separate mixtures of particulate inorganic arsenic compounds and arsine, and to detect and quantify arsenic trioxide vapor. A field study in a lead-acid battery manufacturing plant showed airborne particulate arsenic in Post Burn, Element Battery Repair, and Salvage and Remelt operations; measured widespread low levels of arsine; and suggested that both particulate arsenic and arsine were transported between work areas by in-plant air currents. Arsenic trioxide vapor contributed to the total airborne arsenic collected and was most prevalent in torching or welding areas. This finding suggests that, in the presence of heated arsenic sources, monitoring solely with conventional filters will underestimate arsenic exposure, because arsenic trioxide vapor is not efficiently collected.