In vitro Human Epidermal Penetration of 1-Bromopropane

1-Bromopropane (1-BP; CAS no. 106-94-5), also known as Pr bromide, is a halogenated short-chain alkane used as an organic solvent with numerous commercial and industrial applications, including garment dry cleaning and vapour degreasing of metals. The purpose of this study was to determine the dermal absorption characteristics and corrosivity of 1-BP. Heat-separated human epidermal membranes were mounted on static diffusion cells. Different exposure scenarios were studied (infinite dose, finite dose, and transient exposure) using neat 1-BP and saturated aqueous solution as donor. Steady-state fluxes for infinite-dose neat 1-BP exposure averaged 625 to 960 íg cm-2 h-1. The finite dose (10 íl/cm2) 13.5 mg/cm2) unoccluded donor resulted in penetration of <0.2% of the applied dose (22 íg/cm2). A 10-min transient exposure to infinite dose resulted in total penetration of 179 íg/cm2. Steady-state 1-BP fluxes from neat application of a common dry cleaning solvent were similar (441 to 722 íg cm-2 h-1). The permeability coefficient of 1-BP in water vehicle was 0.257 (0.141 cm/h). The absorption potential of 1-BP following dermal exposure is dependent upon the type and duration of exposure. Donor losses due to evaporation were approximately 500-fold greater than dermal absorption flux; evaporation flux was 420 mg cm-2 h-1. 1-BP is cytotoxic but not corrosive, based on results from a cultured reconstructed human epidermal model (Epi-Derm Skin Corrosivity Test).

Authors: Frasch, H. Frederick; Dotson, G. Scott; Barbero, Ana M. Full Source: Journal of Toxicology and Environmental Health, Part A: Current Issues [online computer file] 2011, 74(19), 1249-1260 (Eng) ;