Zeolites as possible inhibitors of permeation of some metals across the skin

Progress in industry and energetics, urbanisation and other activities are ac companied with metal contamination of the environment. It is thus rather important to prevent the permeation of metals across the human skin. The s kin with its large area (about 2 m(2)), together with other routes of poten tial contamination, could be an important negotiator of whole body intake. Chemically different permeation inhibitors are being tested with the aim to eliminate the toxicological effect of metals in humans. In the present stu dy the use of zeolites was investigated. Synthetic (Zeolon) and natural zeo lite (Mordenite were mixed with Indulona (R) Dez cream at different ratios. Permeation of metals (Cs+, Co2+, Cd2+ ions) from water solution across the intact 5 day-old rat skin was studied in vitro using vertical diffusion ce lls., Tradiometrical method was applied to determine radionuclide permeatio n of the above given metals. Zeolon was found to be a more effective inhibi tor than Mordenite. Comparison of the different zeolibe/Indulona (R) Dez ra tios indicated that the zeolite content in the cream mixture could influenc e its inhibitory effect. Thus for example for Cs, the permeated fraction wa s 0.0054 for the mixture zeolite/Indulona (R) Dez (1:2) and 0.0078 for the mixture zeolite/Indulona (R) Dez (1:4) in the 5(th) experimental hour. For experiments with cobalt, the highest radioactivity was detected in the zeol ite, followed by the stratum corneum (SC) and epidermis, and the lowest in the dermis. Biologically, the principal penetration barrier was found to be the SC. The presented results established the importance of zeolites for c aesium and cobalt permeation inhibition and thus for decreasing their poten tial toxicity. The inhibitory effect of zeolites on cadmium permeation was not confirmed.