High-level, but not low-level, occupational exposure to inhaled anesthetics is associated with genotoxicity in the micronucleus assay

To minimize the possible health risks posed by waste anesthetic gases, the National Institute of Occupational Safety and Health (NIOSH) recommends exp osure limits. We investigated the genotoxicity of a previously established occupational exposure exceeding these Limits (high-level exposure) and of o ne within these limits (low-level exposure). Genotoxicity was assessed by t he formation of micronucleated lymphocytes in 25 anesthetists and anestheti c nurses of an Eastern European (High-Level Exposure Group) and a German (L ow-Level Exposure Group) university hospital. Each exposed group was compar ed with a group of nonexposed personnel of the same hospital. Compared with its Control Group, there was an increased fraction of micronucleated lymph ocytes per 1000 binucleated cells in the High-Level Exposure Group (median 14.0, range 9.0-26.7 vs median 11.3, range 3.2-19.4; P < 0.05) but not in t he Low-Level Exposure Group (median 9.8, range 4.2-20.0 vs median 10.5, ran ge 5.0-20.5). We conclude that a high-level exposure to inhaled anesthetics is associated with an increase in chromosome damage, and measures are reco mmended to decrease exposure levels. As evidenced by the formation of micro nucleated lymphocytes, the threshold values recommended by NIOSH appear to be safe.