Detection of endotoxins in metalworking fluids and metalworking fluid aerosols

A method is presented which allows the concentration of endotoxins in metalworking fluids to be determined. By using this method it was shown that mineral oil based metalworking fluids on average contained higher concentrations of endotoxin and bacteria than synthetic metalworking fluids. In a preliminary study dealing with the concentrations of airborne endotoxins at workplaces using metalworking fluids concentrations of up to 63 EU/m3 air were found. Those are relative low concentrations compared to other workplaces (e. g. animal husbandry). These low concentrations should be mainly the result of effective protective measures like enclosure of machines and the use of local exhaust ventilation systems.