Effect of metal working formulations on biocide absorption in a PDMS membrane coated fiber.
Toxicologist 2009 Mar; 108(1):23
Biocides and preservatives are commonly used in metal working industry applications as additives to extend the shelf life of commercially manufactured aqueous metal working fluid (MWF) formulations. While little is known of the dermal absorption and disposition of these and other MWF formulation components, 5 major classes of these biocides have been associated with occupational contact dermatitis (OCD) in metal machine workers exposed to these mixtures. A PDMS membrane coated fiber (MCF) was exposed to three industrial generic aqueous cutting fluid formulations; soluble oil (SO), semi-synthetic oil (SSYN), and synthetic oil (SYN), as well as surrogate formulations of PEG-200 (PEG) and mineral oil (MO) (to mimic synthetic and soluble oil formulations respectively) at three different concentrations (0.05%, 0.5%, and 5%) to determine the absorption of 37 solutes, including representatives from each of the 5 classes of biocides known to cause OCD. Log Kmcf values were used to quantify dermal absorption and to determine differences between the formulation and/or concentrations. Initial trends indicate that highest absorption occurs at the lowest concentration (absorption at 0.05%> 0.5%>5.0%) across formulations. This trend is best demonstrated in soluble oil (SO) formulation, and Log Ko/w values best correlated with the 0.05% concentration (R2 = 0.77). Changes in absorption of solutes with low log Ko/w values were less likely to be influenced by changes in MWF concentrations, while changes in absorption were magnified at higher Log Ko/w values. The biocide 4-tertiary amylphenol showed its most pronounced absorption difference between the 3 concentrations in the MO formulation, followed by SO, SYN, and then PEG; the later with little or no difference in absorption between the concentrations. These phenomena suggest that there is not only a chemical but also concentration dependent influence on absorption of individual solutes in the presence of more complex formulations or mixtures.
Absorption-rates; Aerosols; Air-flow; Biocides; Chemical-hypersensitivity; Chemical-properties; Chemical-reactions; Contact-allergies; Contact-dermatitis; Dermatitis; Exposure-assessment; Exposure-levels; Exposure-methods; Metallic-compounds; Metalworking; Metalworking-fluids; Metalworking-industry; Occupational-dermatitis; Occupational-exposure; Occupational-hazards; Occupational-health; Skin-exposure; Skin-irritants; Skin-sensitivity; Statistical-analysis; Worker-health; Workplace-studies
Ronald E. Baynes, Center for Chemical Toxicology Research and Pharmacokinetics (CCTRP), College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA
Disease and Injury: Allergic and Irritant Dermatitis
The Toxicologist. Society of Toxicology 48th Annual Meeting and ToxExpo, March 15-19, 2009, Baltimore, Maryland
North Carolina State University, Raleigh, North Carolina