title: In vivo and ex vivo percutaneous absorption of [14C]-bisphenol A in rats: a possible extrapolation to human absorption?
abstract: Bisphenol A (BPA) is a monomer used mainly in the synthesis of polycarbonates and epoxy resins. Percutaneous absorption is the second source of exposure, after inhalation, in the work environment. However, studies on this route of absorption are lacking or incomplete. In this study, percutaneous BPA absorption was measured in vivo and ex vivo in the rat, and ex vivo in humans. An approximately 12-fold difference in permeability between rat skin and human skin was found, with permeability being higher in the rat. In addition, inter- and intra-individual variability of up to tenfold was observed in humans. No accumulation of BPA in the skin was found during exposure. The skin clearance rate following exposure was estimated at 0.4 μg/cm²/h. Ex vivo and in vivo percutaneous absorption fluxes of BPA in the rat were in the same range (about 2.0 μg/cm²/h), suggesting that extrapolation to the in vivo situation in humans may be possible. The European tolerable daily intake (TDI) of BPA is 50 μg/kg body weight. However, many research projects have highlighted the significant effects of BPA in rodents at doses lower than 10 μg/kg/day. A 1-h occupational exposure over 2,000 cm² (forearms and hands) may lead to a BPA absorption of 4 μg/kg/day. This is 8% of the European TDI and is very close to the value at which effects have been observed in animals. This absorption must therefore be taken into account when evaluating risks of BPA exposure, at least until more relevant results on the toxicity of BPA in humans are available.
authors.affiliation: Institut National de Recherche et de Sécurité, rue du Morvan, CS 60027, 54519, Vandoeuvre les Nancy Cedex, France. fabrice.marquet@inrs.fr
authors.forename: Fabrice
authors.initials: F
authors.lastname: Marquet
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Payan
authors.forename: Dominique
authors.initials: D
authors.lastname: Beydon
authors.forename: Ludivine
authors.initials: L
authors.lastname: Wathier
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Grandclaude
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Ferrari
mesh_terms: D000279:Administration, Cutaneous; D000395:Air Pollutants, Occupational / Q000493:pharmacokinetics* / Q000652:urine; D000818:Animals; D001559:Benzhydryl Compounds; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D015194:Diffusion Chambers, Culture; D005243:Feces / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D008297:Male; D008954:Models, Biological; D010636:Phenols / Q000493:pharmacokinetics* / Q000652:urine; D011237:Predictive Value of Tests; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption; D013045:Species Specificity; D000098826:Bisphenol A Compounds
chemical_list: D000395:Air Pollutants, Occupational; D001559:Benzhydryl Compounds; D002250:Carbon Radioisotopes; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds