NICKEL-RELATED CANCER IN WELDERS

During stainless steel (SS) welding, solid aerosols are generated from elemental compounds which are generally considered to be human carcin ogens; i.e. compounds of hexavalent chromium (Cr(VI)) and nickel. Epid emiological studies among groups of SS-welders have indicated that the y may carry a higher risk of acquiring lung cancer than mild steel (MS ) welders using the same welding techniques. This excess risk has been demonstrated in cohort as well as by case-control studies. The presen t evidence does not support the view that exposure to SS-welding fumes poses a hazard of cancer at any other site. Exposure to asbestos and smoking are generally major confounders in these studies. The number o f SS-welders world-wide seems to be increasing, thus these findings ma y be of significance to SS-welders and to the welding industry. Despit e the information on the possible cancer hazard among SS-welders, curr ent epidemiological data on cancer incidence and mortality do not offe r clear evidence to determine whether exposure to nickel or Cr(VI) com pounds constitutes the more important risk factor for lung cancer.