Solvatochromatic interactions influencing dermal permeation of biocides in commercial cutting fluids.
Toxicologist 2008 Mar; 102(1):319-320
Linear salvation energy relationships (LSER) can be used to explain the intermolecular interactions of the solute between 2 phases and to predict the dermal permeability of solutes. The aim of this study is to determine the interactions occurring during dermal permeation of 4 phenolic biocides in 4 different formulations using a LSER approach, with a calibrated flow through diffusion cell system. Infinite doses of 4 biocides and 25 probe chemicals in water, 17% methanol and 2 commercial removal fluids namely Astrocut-C® and Tapfree 2® were applied to porcine skin flow through diffusion cells. The strength coefficients for the 25 probe compounds for each system were determined from multiple linear regression analysis and plugged into the Abraham's LSER equation to predict permeability values for biocides. Biocide permeability significantly decreased in methanol, Astrocut-C® and Tapfree 2® when compared to water. The strength coefficients revealed that hydrophobicity played an important role in explaining the reduced permeability in vehicles when compared to water. This finding is important for selection of biocides and cutting fluid formulations. The R2 between experimental and predicted log Kp of probe solutes for water, methanol, Astrocut-C® and Tapfree 2® were 0.70, 0.78, 0.89 and 0.84 respectively. In conclusion, the LSER approach in part explained several chemical interactions resulting in reduced permeability and also predicted the dermal permeability of 4 biocides in commercial cutting fluids. Further dermal permeability of biocides will be determined in individual and combinations of different components of commercial cutting fluids to ascertain which component has prominent influence in dermal permeability.
Contact-allergies; Contact-dermatitis; Cell-damage; Chemical-hypersensitivity; Mathematical-models; Statistical-analysis; Risk-analysis; Quantitative-analysis; Physiological-chemistry; Physical-reactions; Dermatitis; Skin-absorption; Diffusion-analysis; Analytical-models; Analytical-chemistry; Biochemical-analysis; Biocides; Biohazards; Cutting-oils; Metalworking-fluids
Disease and Injury: Allergic and Irritant Dermatitis
The Toxicologist. Society of Toxicology 47th Annual Meeting and ToxExpo, March 16-20, 2008, Seattle, Washington
North Carolina State University, Raleigh, North Carolina