DNA damage and antioxidant status in medical residents occupationally exposed to waste anesthetic gases

To investigate the effects of occupational exposure to waste anesthetic gases on genetic material and antioxidant status in professionals during their medical residency. The study group consisted of 15 medical residents from Anesthesiology and Surgery areas, of both genders, mainly exposed to isoflurane and to a lesser degree to sevoflurane and nitrous oxide; the control group consisted of 15 young adults not exposed to anesthetics. Blood samples were drawn from professionals during medical residency (eight, 16 and 22 months of exposure to waste anesthetic gases). DNA damage was evaluated by comet assay, and antioxidant defense was assessed by total thiols and the enzymes glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT). When comparing the two groups, DNA damage was significantly increased at all time points evaluated in the exposed group; plasma thiols increased at 22 months of exposure and GPX was higher at 16 and 22 months of exposure. Young professionals exposed to waste anesthetic gases in operating rooms without adequate scavenging system have increased DNA damage and changes in redox status during medical residency. There is a need to minimize exposure to inhalation anesthetics and to provide better work conditions.

Avaliação de genotoxicidade e estresse oxidativo em profissionais recém-expostos aos resíduos de gases anestésicos / Evaluation of genotoxicity and oxidative stress in professionals newly exposed to waste anesthetic gases

Profissionais expostos ocupacionalmente a longos períodos de exposição aos resíduos de gases anestésicos apresentam alterações no genoma. Os dados existentes na literatura em relação ao estresse oxidativo desses profissionais são escassos. O objetivo da presente pesquisa foi avaliar a genotoxicidade e o estresse oxidativo em profissionais recém-expostos aos resíduos de gases anestésicos. O estudo foi realizado em 15 médicos residentes da Anestesiologia e Cirurgia, de ambos os sexos, os quais estiveram sob exposição aos resíduos de gases anestésicos isoflurano, sevoflurano e óxido nitroso (N2O). Como grupo controle, 15 voluntários que não frequentavam o ambiente hospitalar foram avaliados. Coletas de sangue foram realizadas após oito, 16 e 22 meses de exposição no grupo exposto e uma vez no grupo controle. Para avaliação da genotoxicidade, utilizou-se o teste do cometa para detecção de quebras de fitas no DNA. Para avaliação de estresse oxidativo foram determinados o conteúdo total de tióis e as proteínas carboniladas, além das enzimas antioxidantes superóxido dismutase (SOD), catalase (CAT) e glutationa peroxidase (GSH-Px). A exposição ocupacional aos resíduos de gases anestésicos mostrou-se genotóxica nos três períodos de exposição avaliados em relação ao grupo controle. Quanto às proteínas carboniladas, houve diminuição significativa de seus valores no grupo de residentes após 16 meses de exposição em relação ao grupo controle. O conteúdo total de tióis foi significativamente maior no grupo exposto após 22 meses de exposição, quando comparado ao grupo controle. Em relação ao sistema de defesa antioxidante, não foram detectadas diferenças significativas de SOD e CAT entre os grupos...

Professionals occupationally exposed for several years to waste anesthetic gases present damages in the genome. Literature data regarding oxidative stress in operating room personnel are scarce. The aim of this study was to evaluate the genotoxicity and oxidative stress in professionals newly exposed to waste anesthetic gases. The study was conducted in 15 residents of Anesthesiology and Surgery, of both sexes, who were exposed to the following waste anesthetic gases: isoflurane, sevoflurane and nitrous oxide (N2O). As a control group, 15 volunteers who did not attend to the hospital were evaluated. Blood samples were collected after eight, 16 and 22 months of exposure in the medical residents and at once in the control group. For genotoxicity, the comet assay was utilized to detect DNA breaks. For oxidative stress, carbonyl protein and total thiols, besides antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were evaluated. Occupational exposure to waste anesthetic gases shown to be genotoxic in all exposure times compared to the control. A significant decrease of carbonyl proteins after 16 months of exposure was detected in the group of residents, when compared to the control group. The thiols were significantly higher in the exposed group after 22 months of exposure, when compared to the control group. Regarding the antioxidant defense system, no significant differences were found in SOD and CAT between groups. GSH Px increased in the exposed group after 16 and 22 months compared to the control group...