Cytotoxic effects of dicyclohexylamine and three metalworking fluids on human epidermal keratinocytes.
Linthicum-AD; Inman-AO; Monteiro-Riviere-NA; Baynes-RE
Toxicologist 2013 Mar; 132(1):222
Many of the 1.2 million workers in the metal machining industry within the United States will be exposed to metalworking fluids via the dermal route, making it a major occupational health and safety concern. Dicyclohexylamine (DCHA), an anticorrosive agent used in the metalworking industry to prevent corrosion of fabricated materials, is known to permeate the skin and could potentially elicit a toxic response on human epidermal keratinocytes (HEK). HEK were exposed only to DCHA or one of the following three generic metalworking fluids: soluble oil, synthetic oil and semi-synthetic oil for 24h. Cells were dosed with solutions ranging from concentrations of 200-5000 microg/ml. The highest concentration of 5000 microg/ml is the relevant occupational exposure dose in the metal machining industry. Cells exposed to 200-5000 microg/ml of DCHA resulted in a 24-91% decrease in cell viability in comparison to the media control. The soluble oil and semi-synthetic oil dosed from 200-5000 microg/ml resulted in an 80-83% and 81-85% decrease in cell viability, respectively, in comparison to the media control. For synthetic oil, there was a 52-85% decrease in cell viability in comparison to the media control. DCHA and all metalworking fluid treatments caused a significant (p<0.05) decrease in HEK viability. In conclusion, metalworking fluids and DCHA had a cytotoxic effect to HEK. This data suggests that the concentration of DCHA in metalworking fluid formulations should be reduced while safer metalworking fluid formulations are developed.
Toxicology; Laboratory-techniques; Exposure-levels; Dose-response; Immune-reaction; Cell-function; Cellular-reactions; Cytotoxic-effects; Metal-industry; Metal-industry-workers; Metal-workers; Metalworking; Metalworking-fluids; Metalworking-industry; Skin-exposure; Skin-irritants; Skin-sensitivity; Cyclohexylamines; Allergic-dermatitis; Corrosion-inhibitors; Corrosion-resistant-coatings; Skin-absorption; Synthetics; Oil-dermatitis; Oils; Machine-operators; Cell-damage; Cell-cultures; Fluids; Employee-exposure
The Toxicologist. Society of Toxicology 52nd Annual Meeting and ToxExpo, March 10-14, 2013, San Antonio, Texas
North Carolina State University, Raleigh, North Carolina