Potential health and environmental issues of mercury-contaminated amalgamators.
BACKGROUND
Dental amalgamators may become contaminated internally with metallic mercury. This contamination may result from mercury leakage from capsules during trituration or from the long-term accrual from microscopic exterior contaminants that result from the industrial assembly process. The potential health risk to dental personnel from this contamination is unknown.


METHODS
The authors assessed used amalgamators from the federal service inventory for the amounts of mercury vapor levels, as well as the visual presence of mercury contamination. They evaluated these amalgamators for potential mercury vapor health risk, using established National Institute for Occupational Safety and Health methods and American Conference of Governmental Industrial Hygienists standards.


RESULTS
Ten of the 11 amalgamators assessed had measurable mercury vapor levels. Four amalgamators were found to have internal static mercury vapor levels above Occupational Safety and Health Administration ceiling limit thresholds. During a simulated worst-case clinical use protocol, the authors found that no amalgamators produced mercury vapor in the breathing space of dental personnel that exceeded established time-weighted federal mercury vapor limits.


CONCLUSIONS
Amalgamators may be contaminated internally with metallic mercury. Although the authors detected mercury vapor from these units during aggressive, simulated clinical use, dilution factors combined with room air exchange were found to keep health risks below established federal safety thresholds.


CONCLUSIONS
Dental personnel should be aware that amalgamators may be contaminated with mercury and produce minute amounts of mercury vapor. These contaminated amalgamators may require disposal as environmentally hazardous waste.
Roberts
H W
HW
USAF Dental Investigation Service, Detachment 1, USAFSAM, 310C B St., Building 1H, Great Lakes, Ill. 60088, USA. howard.roberts@ndri.med.navy.mil
Leonard
D
D
Osborne
J
J
D016902:Air Pollution, Indoor / Q000032:analysis; D003723:Dental Amalgam / Q000737:chemistry; D003748:Dental Equipment; D003797:Dental Staff; D003800:Dental Technicians; D018057:Dental Waste; D004866:Equipment Contamination; D006256:Hazardous Waste; D006801:Humans; D008628:Mercury / Q000032:analysis; D016273:Occupational Exposure; D014835:Volatilization
D018057:Dental Waste; D006256:Hazardous Waste; D003723:Dental Amalgam; D008628:Mercury