A 53-year-old woman worked as a dental laboratory technician for 13 years, sandblasting beryllium dental alloy, cutting the metal sprue from the allow with a high-speed grinder, removing the bubbles with a hand-held electric grinder and deburrer, and setting the restoration to ensure it fit. She wore a surgical-type paper mask while working, and although a vacuum system with moveable hoses was available for cleanup, the lab was reportedly very dusty.
Beginning in 1996, she went to work at a different dental laboratory, where she ground porcelain restorations, sandblasted and polished restorations. She also was involved in cleanup activities, including removing the bag from the vacuum and shaking it, producing a cloud of dust.
Not too surprisingly, she was diagnosed with chronic beryllium disease, a debilitating and often fatal lung disease, in May 2000. She suffers from a dry cough, decreased energy, and is unable to walk up more than a flight of stairs without experiencing shortness of breath. She never received any training in the hazards of beryllium exposure, according to the Occupational Safety and Health Administration (OSHA), and was never taught how to work safely with it.
To protect other workers, OSHA issued a new Hazard Information Bulletin today to alert dental laboratories on how to prevent exposure to beryllium. Exposure to beryllium can cause chronic beryllium disease (CBD) and lung cancer.
"Inhaling beryllium dust at some concentrations is extremely hazardous - sometimes deadly," said OSHA Administrator John Henshaw. "We are concerned that dental lab technicians are continuing to contract the disease associated with beryllium exposure. This bulletin informs dental labs and workers of the potential hazards and offers effective methods to prevent exposure to beryllium."
The Hazard Information Bulletin recommends the types of engineering controls, work practices, training, personal protective equipment and housekeeping procedures that can be used to reduce beryllium exposure and the risk of CBD. It also provides information on a health surveillance tool that can be used to identify workers with CBD, or beryllium-sensitized individuals, who are at a high risk of progressing to CBD.
Dental laboratory technicians can develop CBD if they inhale dust containing beryllium when working on items such as dental crowns, bridges and partial denture frameworks made from dental alloys containing beryllium. CBD may develop within months after initial exposure to beryllium or may have a very slow onset and not develop until years after exposure to beryllium has occurred.
Not all dental alloys contain beryllium. Dental laboratories and technicians should inquire about the contents of the alloys they are using. Information about the contents of dental alloys can be found in the Material Safety Data Sheets (MSDS) that accompany these products to the dental laboratory.
Under OSHA''s current beryllium standard, employees cannot be exposed to more than 2 micrograms of beryllium per cubic meter of air for an 8-hour time-weighted average. Recent information suggests that compliance with this exposure limit is not adequate for preventing the occurrence of CBD. The Hazard Information Bulletin calls for, to the extent feasible, the use of improved engineering controls and work practices.
The Hazard Information Bulletin is available on the OSHA Web site at www.osha.gov/dts/hib/hib_data/hib20020419.pdf.
by Sandy Smith ([email protected])