Qualitative assessment of isocyanate skin exposure in auto body shops: a pilot study

Little is known about the extent of human isocyanate skin exposure in auto body shops and the effectiveness of personal protective equipment. Animal studies have suggested that skin exposure to isocyanates may be an important risk factor for respiratory sensitization leading to asthma. This study provides initial data on hexamethylene diisocyanate skin exposure in three auto body shops.

Three auto body shops of different size which use different paint systems were examined for the presence of aliphatic isocyanates on environmental surfaces and workers' skin and for breakthrough of personal protective equipment. Qualitative detection of contamination by isocyanates was conducted using a wipe-sampling technique. Assessment focused on the painters and their tasks, although other auto body repairers were also evaluated.

Environmental surfaces such as painters' workbenches, spray equipment, and cleaning tools were found contaminated with isocyanates. Painters had frequent contact with contaminated surfaces, often without wearing gloves. Moderate to heavy contamination of some skin surfaces was found with painters from two of the three auto body shops. Latex gloves used for skin protection showed significant penetrations by isocyanates even after a single painting session.

Contaminated environmental surfaces and skin exposure to isocyanates were documented in several auto body shops. Latex gloves were not adequate protection for workers using isocyanate paints. Further research which would better quantify skin exposure, and its potential relationship to respiratory sensitization and asthma is warranted.