IntroductionElectric arc welding of steel is at the centre of the industrialised and industrialising world. With an estimated three million workers around the world using it in some form or another and many more exposed at work to fumes arising from the processes, even a slight excess risk of a serious, commonly fatal disease such as lung cancer would result in a significant number of deaths globally. Welders have a 30 - 40% excess risk of developing lung cancer compared to the general population.1-6
Research to find a specific causal relationship is especially difficult because lung cancer is the commonest malignancy in the Western world. There is a need for more and better investigation but enough is known now to allow useful preventive action to be taken by applying occupational hygiene principles.