Study of the volatile organic compounds (VOCs( in the exhaust air from low heat sterilizer devices of four hospitals in Tehran

Background and aims: Application of low heat devices was increased for infectious waste sterilizing in many hospitals in Iran. Studies have shown that the generation of volatile organic compounds (VOCs) and hazardous materials is most probable in the exhaust air of these devices. The main objective of this research is study of VOCs ( in the exhaust air from low heat sterilizer devices of four hospitals in Tehran city. Methods: This research was accomplished in some hospitals using sterilizer devices such as: Hydroclave, Autoclave-shredder, Autoclave without shredder and Heat dryer. Ten samples were taken from each device every week from April to July 2011. Sampling was done by NIOSH 1501 method. Samples were analyzed in two qualitative and quantitative phases by GC-MASS and the obtained results were compared with occupational exposure short term limits (OEL- STEL) recommended by Center for Environmental and Occupational Health, Iranian Ministry of Health. Results: In the first phase of research (qualitative analysis), in 90% of samples only BTEX compounds(Benzene, Toluene, Ethyl Benzene and Xylene) were observed. Based on the results of the second phase, the highest and the lowest concentration of BTEX with 9.35 ppm and 1.25 ppm were determined to be related to Autoclave-shredder and Autoclave without shredder, respectively. According to exhaust air clarity, Autoclave without shredder, Hydroclave, Heat dryer and Autoclave-shredder were scored from 1 to 4, respectively. Conclusion: The concentrations of Benzene, Toluene, Ethyl Benzene and Xylene in all samples were lower than the occupational exposure short term limits. The presence of VOCs in the majority of collected samples, considering the short lifetime of these devices (between 3 to 9 months), confirmed that there is a high potential risk of exposureresulted by these devices. Therefore, monitoring of exhaust air quality of such devices is required. Keywords : low heat waste sterilizers hospital wastes volatile organic compounds BTEX air