Toxic metals, including "heavy metals," are individual metals and metal compounds that negatively affect people's health. Some toxic, semi-metallic elements, including arsenic and selenium, are discussed in this page. In very small amounts, many of these metals are necessary to support life. However, in larger amounts, they become toxic. They may build up in biological systems and become a significant health hazard. This page provides a starting point for technical and regulatory information about toxic metals.
Common sources of exposure to higher-than-average levels of arsenic include near or in hazardous waste sites and areas with high levels naturally occurring in soil, rocks, and water. Exposure to high levels of arsenic can cause death.
Elemental beryllium has a wide variety of applications. Occupational exposure most often occurs in mining, extraction, and in the processing of alloy metals containing beryllium. Beryllium can cause sensitization, lung and skin disease in a significant percentage of exposed workers.
Cadmium is an extremely toxic metal commonly found in industrial workplaces, particularly where any ore is being processed or smelted. Several deaths from acute exposure have occurred among welders who have unsuspectingly welded on cadmium-containing alloys or with silver solders.
Calcium chromate, chromium trioxide, lead chromate, strontium chromate, and zinc chromate are known human carcinogens. An increase in the incidence of lung cancer has been observed among workers in industries that produce chromate and manufacture pigments containing chromate.
Occupational exposure to lead is one of the most prevalent overexposures. Industries with high potential exposures include construction work, most smelter operations, radiator repair shops, and firing ranges.
Common sources of mercury exposure include mining, production, and transportation of mercury, as well as mining and refining of gold and silver ores. High mercury exposure results in permanent nervous system and kidney damage.
- National Emphasis Program – Primary Metal Industries. OSHA Directive CPL 03-00-018, (October 20, 2014).
- New OSHA National Emphasis Program will help protect workers from chemical and physical hazards in the primary metals industries. OSHA Trade News Release, (June 2, 2011).