Exposure assessment for formaldehyde and acetaldehyde in the workplace

Personal exposure and possible cancer risk to formaldehyde and acetaldehyde were appraised in 8 work places at a university in Brazil. Levels of formaldehyde measured ranged from 22.5 to 161.5 mu g(.)m(-3) and from 18.3 to 91.2wg(.)m(-3) for acetaldehyde. The personal exposure, expressed as the potential dose in indoor air, was calculated to range from 129.8 to 930.4 mu g(.)day(-1) (low exposure) and 183.9 to 1318.1 mu g(.)day(-1) (medium exposure) for formaldehyde and 105.5 to 525.3 mu g(.)day(-1) (low exposure) and 149.5 to 744.2 mu g(.)day(-1) (medium exposure) for acetaldehyde. The indoor/outdoor ratio showed the existence of indoor sources of the compounds which were mainly in practical classes and research laboratories. The highest formaldehyde and acetaldehyde levels were found where chemical reagents were manipulated. Relating the levels found to the permissible limit given by the US OSHA showed there was no particular risk although some formaldehyde levels did exceed the lower exposure limit of the US agency NIOSH. Any cancer risk would be highest for female technicians and teaching researchers.