Abstract Introduction Inhaled anesthetics are used worldwide for anesthesia maintenance both in human and veterinary operating rooms. High concentrations of waste anesthetic gases can lead to health risks for the professionals exposed. Considering that anesthetic pollution in a veterinary surgical center in developing countries is unknown, this study aimed, for the first time, to measure the residual concentration of isoflurane in the air of operating rooms for small animals in a Brazilian university hospital. Method Residual isoflurane concentrations were measured by an infrared analyzer at the following sites: corner opposite to anesthesia machine; breathing zones of the surgeon, anesthesiologist, and patient (animal); and in front of the anesthesia machine at three time points, that is, 5, 30 and 120 minutes after anesthesia induction. Results Mean residual isoflurane concentrations gradually increased in the corner opposite to anesthesia machine and in the breathing zones of the surgeon and the anesthesiologist (p < 0.05). There was an increase at 30 minutes and 120 minutes when compared to the initial time points in the animal's breathing zone, and in the front of the anesthesia machine (p < 0.05). There was no significant difference at measurement sites regardless of the moment of assessment. Conclusion This study reported high residual isoflurane concentrations in veterinary operating rooms without an exhaust system, which exceeds the limit recommended by an international agency. Based on our findings, there is urgent need to implement exhaust systems to reduce anesthetic pollution and decrease occupational exposure.

RESUMO: O fipronil é um inseticida/herbicida amplamente utilizado para controle de pulgas e carrapatos em animais domésticos. Sua exposição a curto prazo tem acarretado efeitos deletérios em animais. Entretanto, o possível efeito genotóxico deste composto ainda não foi investigado em animais alvo. Baseando-se na hipótese de que o fipronil pode induzir genotoxicidade, o presente estudo avaliou o efeito deletério do fipronil no material genético de células de sangue periférico. Para isso, dez cães sadios, de ambos os sexos, foram utilizados neste estudo. O produto (6,7mg/kg) foi aplicado na região dorsal do pescoço de cada animal. As amostras de sangue foram coletadas imediatamente antes da aplicação do produto (controle) e após três, oito e 24 horas da aplicação. As amostras foram imediatamente processadas para condução do teste do cometa, a fim de se avaliar os danos basais no DNA. Não houve diferença significativa entre os quatro momentos de coleta em relação aos danos no material genético. O estudo sugere, pela primeira vez, que uma exposição única a este pesticida não induz efeito genotóxico sistêmico em cães.

ABSTRACT: Fipronil is a pesticide widely used for controlling fleas and ticks in domestic animals, and its short-term exposure can lead to serious effects on animals. However, the possible genotoxic effect of this compound has not been investigated in target animals. Based on the hypothesis that fipronil can induce genotoxicity, this study evaluated the effect of fipronil on DNA damage in peripheral blood cells. For that purpose, ten dogs of both sexes were used in the study. The product (6.7mg/kg) was applied on the dorsal neck region of each animal. Peripheral blood samples were collected immediately prior to application of the product, and at 3, 8 and 24 hours after the application. Samples were processed for comet assay. No statistically significant differences were found among the four time points. The current study suggests for the first time that a single exposure to this pesticide does not induce systemic genotoxic effect in dogs.