Ethanolamine Exposures of Workers Using Machining Fluids in the Automotive Parts Manufacturing Industry

Abstract

Ethanolamines (EAs) are present in machining and grinding fluids and have the potential to act as respiratory irritants and sensitizing agents. EA levels in bulk cutting fluids were determined and compared with information available in the material safety data sheets (MSDSs), and the exposure to EAs of workers in the auto parts manufacturing industry was characterized. Monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA) were all present in bulk machining fluids at levels ranging from 1 percent to 11 percent, 4 percent to 5 percent, and 0.3 percent to 40 percent, respectively. The MSDSs provided a general guideline to the presence or absence and relative levels of alkanolamines as a class, but were not generally useful as a guide to the presence or relative amount of specific EAs. This was particularly the case with MEA.

Air levels of TEA in the personal samples were generally higher for transfer operations and lowest for assembly workers, who do not use machining fluids in the course of their work. TEA air levels were related in an operation-specific manner with TEA levels in the bulk machining fluid formulations. No consistent relationship was observed between TEA and particulate mass nor was there evidence of preferential partitioning of TEA between particle size fractions.