(including Chrome VI)

It is estimated that 1.2 million full time workers are involved in welding and its related activities across the EU27. Fumes and dusts generated during the welding process can potentially contain carcinogenic compounds of Chromium VI, Nickel and Cobalt and other hazardous substances.

Welding fumes have been classified carcinogenic to humans (Group 1) by the IARC. Occupation as a welder is estimated to be associated with a siginificant increase in lung cancer risk which can be caused by inhaltation of dust and fumes from welding metals.

Where risks occur

Welding fumes are formed when metals are heated above their boiling point (vapourised) and their vapours rapidly condense into very fine particles (solid particulates or dust). The key metals that are used across Europe are steel (unalloyed and low-medium alloyed), stainless steel (cast iron and nickel base) and aluminium and aluminium alloys.

Gas welding, arc welding, beam welding, soft soldering, hard soldering, brazing, thermal cutting or gouging, flame straightening, and thermal spraying are the most relevant welding processes during which carcinogenic dusts and fumes might be generated.
Exposure to welding fumes occurs in multiple sectors such as shipbuilding, automotive and mechanical engineering, construction (i.e. bridges, stairs, balconies), plumbing, transportation and in telecommunication. Occupations are mainly welders, flamecutters and metal workers and those workers that work close by.

More about the substance

The type of welding process used will impact the nature and extent of dangerous substances produced in the dusts and fumes. The fume emitted by welding and hot cutting processes is a varying mixture of hazardous substances which can be inhaled. The composition of welding fumes will depend on the base and filler material and welding technique. Welding techniques that have the highest emission rates are laser welding with filler materials, MIG (solid wire, nickel, nickel-based alloys), MAG (solid wire and flux-cored with and without shielding gas), laser cutting, autogenous flame cutting, plasma cutting, arc spraying and flame spraying. Potentially released carcinogens during welding processes are compounds of beryllium, cadmium, chromium VI, cobalt and nickel.

How symptoms can affect you

Acute exposure to welding fume and gases can result in eye, nose and throat irritation, dizziness and nausea as well as metal fume fever. Prolonged exposure to welding fume may cause lung damage and various types of cancer, including lung, larynx and urinary tract. The main non-cancer diseases are acute or chronic effects in the respiratory tract like COPD, occupational asthma and welder’s lung. However, UV-light emitted during welding may also cause ocular melanoma. Fumes released during mild steel welding (and the presence of Manganese in the steel), can lead to neurological symptoms similar to Parkinson’s disease. These symptoms include speech and balance disorders.

What you can do

The exact level of risk from welding fumes will depend on three factors: how toxic the fume is, how concentrated it is and how long you are breathing it. Can the fume be eliminated by changing to a cold process (e.g. guillotine) or can different consumables (cleaner rods/wires) be used? If not, the best solution is to minimise the fume by re-designing the work and reconsidering the techniques and materials used, for instance the extracted welding torch. Secondly, solutions could be installation of efficient general and local ventilation (LEV) systems and correct positioning (standing upwind). If adequate control from LEV cannot be provided, or if it is not reasonably practicable to provide LEV, workers should use suitable respiratory protective equipment (RPE). For work of up to an hour a FFP3 disposable mask or half-mask with P3 filter is recommended. For longer duration work use battery-powered air-fed protective equipment, with a minimum assigned protection factor of 20 (APF20). Ensure providing a face-fit testing for the RPE. For welding outdoors, LEV will not work, so workers should use suitable RPE to control exposure. Welders should understand the hazards of the materials they are working with. Investigation if workers report early symptoms is advisable.

References: Impact Assessment study report, ECHA study report, EU-OSHA, HSE, IARC