Metal Information Center

Chromium in biological samples from low-level exposed stainless steel and mild steel welders

October 10, 2007 – 7:03 am

OCCUPATIONAL EXPOSURE to hexavalent chromium is of concern because of its mutagenic and carcinogenic actions. [1,2] Welding of stainless less (SS) with the manual metal arc (MMA) method may be associated with substantial pulmonal absorption and urinary excretion of chromium. [3-7] The emission of hexavalent chromium at tungsten inert gas (TIG) SS and mild-steel (MS) welding is much lower compared with MMA/SS welding. (Stainless stell is an alloy of iron, nickel, and chromium. Mild steel is an alloy of iron, carbon, and silicon.) Knowledge of the magnitude of internal exposure to chromium associated with TIG/SS and MS welding is, however, very limited. Two studies found urine chromium concentrations of TIG/SS welders in the range of population-based normal values, [8,9] Although the risk for delayed health effects from long-term, low-level exposure to chromium is questionable, it should be recognized that the number of TIG/SS and MS welders throughout the world is high and is increasing relative to the number of SS welders who use the MMA methods. The aim of this study was to examine the internal exposure to chromium among TIG/SS and MS welders who, to date, have not been considered to be at risk from chromium exposure.