Occupational Exposure of a Medical School Staff to Formaldehyde in Tehran

Cadavers are preserved in a fixing solution containing formalin. Formaldehyde (FA) released from formalin is inhaled by the personnel in the anatomy laboratory. Exposed personnel have reported respiratory problems and various symptoms. Due to the toxicity of FA as a strong irritant and carcinogen and also lack of a national study assessing occupational exposure to FA in gross anatomy labs in Iran, the present study aimed at occupational monitoring of personnel exposed to FA and evaluating relevant symptoms in them. A total of 20 subjects (all the staff) working in a gross anatomy lab and 20 library personnel were considered for occupational monitoring of exposure to FA during three months with various climatic conditions. They were also monitored for respiratory symptoms. Air sampling and analysis of its FA content were conducted according to the NIOSH method No.2016. Symptoms of cases and controls (library personnel) with active and passive exposure to formaldehyde were also studied by a self-report questionnaire. In the first stage of monitoring with ventilation (supply-exhaust) system on, the exposure of personnel (Mean± SE) was 306 ± 21ppb. In the second stage of monitoring the personnel's exposure was 317 ± 26ppb with only the ventilation supply system on and in the final monitoring stage this rate was 698 ± 34ppb with the ventilation system (supply and exhaust) off. In this study, personal’s exposure level to FA was higher than the indoor concentration, and the individual exposure levels of instructors were higher than those of the students. Exposure of library personnel in the adjacent department (central library) was about 50ppb. Most important complaints reported by actively exposed staff members and library personnel were the unpleasant odor (68%), cough (64%), throat irritation and runny nose (56%), burning and itching of nose (52%) and irritating eyes (48%). Considering the level of exposure of all subjects in this study and existence of clinical symptoms, better control of the exhaust system in the gross anatomy lab and use of a more efficient ventilation system are recommended to protect the staff and instructors of the Anatomy Department.