OSHA Issues Hazard Alert on Welder’s Anthrax

Inhalation of ferrous and other metal fumes may predispose metalworkers to a new form of severe pneumonia called welder’s anthrax, OSHA warns in a hazard alert (PDF). Welder’s anthrax is “a newly identified, deadly occupational disease” caused by Bacillus group bacteria that produce anthrax toxin, according to the authors of a March 2022 paper in the journal Pathogens. The hazard alert explains that these bacteria are found naturally in soils in and near subtropical locations. Seven metalworkers from Texas and Louisiana were diagnosed with welder’s anthrax during 1994–2020. Although welder’s anthrax is rare, researchers believe that cases may have been missed due to several factors, including limited detection and understanding of the pathogen.

The hazard alert urges employers with welding operations to implement several recommendations to help prevent employee exposures to anthrax bacteria. For example, OSHA recommends reducing workers’ exposures to environmental dust and welding fumes by using directional airflow from local exhaust ventilation to keep dust and fumes away from welders’ breathing zones. If welding is being performed outdoors, wind may be used for this purpose. Employers should also consider adding disinfectants to metalworking fluids to inhibit microbial contamination, OSHA says. Other recommendations include educating metalworkers about the symptoms of pneumonia, including welder’s anthrax, as well as cleaning the workplace to reduce workers’ exposure to dust and soils that may be contaminated with harmful bacteria. The alert also discusses personal protective equipment, including coveralls, work boots, and NIOSH-approved respirators.

OSHA does not have a standard that applies to welder’s anthrax, but the agency’s respiratory protection standard may apply to some workers whose jobs require them to wear respirators.

The hazard alert is available as a PDF from OSHA’s website. Further information about welder’s anthrax can be found in news articles previously published by AIHA in April 2022 and October 2021.