What is being done about manganese exposure causing manganism?
Researchers are still investigating link between welding rod fumes and manganism. Welding rod litigation has now begun to help those who suffer ill health effects of welding and manganese exposure.
Efforts are being made to reduce risk of environmental manganese exposure. In 1994, U.S. Environmental Protection Agency (EPA) denied a petition by Ethyl Corporation to allow use of methylcyclopentadienyl manganese tricarbonyl (MMT) in unleaded gasoline, because of health concerns related to inhalation of manganese fumes (Davis, 1999).
Other environmental laws have been enacted to limit manganese exposure and welding fume toxicity. However, some scientists feel that more needs to be done about manganism and welding fumes. Researchers studying health effects of welding fumes report a "preponderance of proof for manganese neurotoxicity" even in present-day industrial settings (Iregren 1999).
According to U.S. Department of Labor Mine Safety and Health Administration, Welding Fumes Sampling is required due to "potential hazards of welding operations including metal fumes, toxic gases, and ultraviolet and infrared radiation. Fume particles are formed from vaporization of molten metal. They are very fine in size, generally one micron or smaller, and may join together to form larger particles. Welding fumes can be sampled by drawing air through a special filter at a controlled rate.
“The adverse health effects of welding exposure include chronic or acute systemic poisoning, metal fume fever (a short-term painful ailment with symptoms of fever and chills), pneumoconiosis (lung disease due to accumulation of mineral or metallic particles), and irritation of respiratory tract.
"The welding fumes produced at welding operations depend primarily on composition of metals being welded and welding rods. When base metal is iron or steel, with welding rods of similar composition, main component of welding fume will be iron oxide. When welding on stainless steel, welding fumes containing nickel and chromium may be produced. Welding on plated, galvanized or painted metals may generate fumes containing cadmium, zinc oxide or lead. In addition, welding rods can generate fluoride and free silica in fumes, depending on composition of welding rod coating.
“In summary, welding processes may generate many different metal fumes and other toxic components. It is important that hazards of a welding operation be evaluated properly. Toxic gases that arise in welding include carbon monoxide, nitrogen dioxides and ozone. If welding or cutting operations are conducted in presence of chlorinated hydrocarbons, such as form of solvents either on metals or in air, hazardous concentrations of phosgene and hydrogen chloride, which are highly toxic irritant gases, may be produced.