Mixture additives inhibit the dermal permeation of the fatty acid, ricinoleic acid.
Toxicol Lett 2004 Feb 28; 147(1):15-26
Ricinoleic acid (RA) like many of the ingredients in machine cutting fluids and other industrial formulations are potential dermal irritants, yet very little is known about its permeability in skin. 3H-ricinoleic acid mixtures were formulated with three commonly used cutting fluid additives; namely, triazine (TRI), linear alkylbenzene sulfonate (LAS), and triethanolamine (TEA) and topically applied to inert silastic membranes and porcine skin in vitro as aqueous mineral oil (MO) or polyethylene glycol (PEG) mixtures. These additives significantly decreased ricinoleic acid partitioning from the formulation into the stratum corneum (SC) in PEG-based mixtures. Except for LAS, all other additives produced a more basic formulation (pH = 9.3-10.3). In silastic membranes and porcine skin, individual additives or combination of additives significantly reduced ricinoleic permeability. This trend in ricinoleic acid disposition in both membranes suggests that the mixture interaction is more physicochemical in nature and probably not related to the chemical-induced changes in the biological membrane as may be assumed with topical exposures to potentially irritant formulations.
Cutting-oils; Dermatitis; Skin-absorption; Skin-exposure; Skin-irritants; Skin-sensitivity; Acids; Chemical-composition; Chemical-hypersensitivity; Chemical-properties
Disease and Injury: Allergic and Irritant Dermatitis
North Carolina State University, Raleigh, NC