A chemical commonly used in commercial car and truck washes causes corrosive burns and “potentially fatal systemic toxicity” to workers exposed to it, the U.S. Centers for Disease Control and Prevention (CDC) said in a new report Friday.
Car and truck wash cleaning products, rust removers, and aluminum brighteners often contain hydrofluoric acid because it is highly effective in breaking down roadway dirt and debris, removing rust, and polishing metal surfaces.
The CDC based its report on research conducted by the Washington State’s Department of Labor and Industries, which analyzed workers’ compensation injury reports from 2012-2013 and found that 48 car wash workers experienced chemical burns on the job ranging from superficial (first-degree) burns to full-thickness (third-degree) burns.
The workers received the burn injuries from exposure to cleaning fluids that contained hydrofluoric acid concentrations of .5 percent to 20 percent.
The workers suffered chemical burns to their hands, fingers, arms, head, or eyes by wearing improper or defective gloves, or not wearing gloves. In one case, a hydrofluoric acid cleaning solution dripped down a brush handle and burned the arm of a worker who was wearing all the proper protective gear but was cleaning overhead. In fewer cases, workers suffered burns to the torso and lower extremities.
One worker, a 38-year-old man, died after ingesting a hydrofluoric acid-based liquid, which is colorless and odorless. It is uncertain, however, whether the ingestion was accidental or intentional.
The CDC report said that hydrofluoric acid “is insidiously toxic at the low concentrations (<20%) used in vehicle washing” because burns may initiate with little or no pain or irritation, yet the acid’s fluoride ion penetration progresses to nerve and tissue damage if the burn goes untreated.
“Fluoride toxicity by any route of exposure can cause fatal cardiac arrhythmias precipitated by hypocalcemia and hyperkalemia” the CDC report said.
Numbness, induced by the nerve damage resulting from fluoride ion penetration, leaves the injured worker unaware of the underlying necrosis that can progress for up to 24 hours after exposure. Topical application and subcutaneous administration of calcium or magnesium compounds can be used to quench fluoride ions and preempt tissue damage.
The CDC report also mentioned two serious chemical burn injury cases in Oregon, including one that resulted in the amputation of a finger.
“Occupational exposure to hydrofluoric acid-based wash solutions can result in chemical burns, disability, and death,” the CDC concluded. “Hydrofluoric acid’s potential to cause severe injury combined with the inherent challenge of relying on [personal protective equipment] to protect workers warrants efforts to identify less hazardous alternatives, which would provide the most effective means of prevention.”