title: The in vitro permeability of human skin to benzene, ethylene glycol, formaldehyde, and n-hexane.
abstract: The permeability of human skin to benzene, ethylene glycol, formaldehyde, and n-hexane was studied using excised skin in a flow-through diffusion cell. The rate of resorption was determined by measuring the amount of substance found in the receptor fluid beneath the skin at steady-state. The rates of resorption (microgram X cm-2 X hr-1) were: benzene 99. ethylene glycol 118, formaldehyde from a concentrated solution of formalin 319, formaldehyde from a solution of 10% formalin in phosphate buffer 16.7, and n-hexane 0.83. The amount of substance in the skin at steady-state and after 0.5 hr of exposure was also determined. For all substances, the sum of the amount in the receptor medium and in the skin at steady-state, were larger than the amount obtained by multiplying the resorption rate by the time of exposure. For benzene, ethylene glycol and n-hexane the amount absorbed during the first half-hour of exposure was considerable larger than the amount resorbed during a same unit of time at steady-state. These data call attention to the fact that the absorption rate is higher before steady state is attained.
mesh_terms: D001554:Benzene / Q000378:metabolism*; D019855:Ethylene Glycol; D005026:Ethylene Glycols / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism*; D006586:Hexanes / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D012869:Skin Absorption; D013997:Time Factors
chemical_list: D005026:Ethylene Glycols; D006586:Hexanes; D005557:Formaldehyde; C026385:n-hexane; D019855:Ethylene Glycol; D001554:Benzene