title: The percutaneous absorption of hydroquinone (HQ) through rat and human skin in vitro.
abstract: Because of the potential for human contact with photographic developer solutions containing hydroquinone (HQ), the rates of percutaneous absorption of HQ through human stratum corneum and full-thickness rat skin have been measured in vitro using 5% aqueous solutions of HQ as the donor solutions. The studies were performed using infinite doses of aqueous solutions containing 14C-labeled HQ in Franz-type diffusion cells. The measured absorption rate (mean +/- S.D.) of HQ through human stratum corneum was 0.52 +/- 0.13 micrograms/cm2/h, while that for full-thickness rat skin was 1.1 +/- 0.65 micrograms/cm2/h. The ratio (rat/human) of the permeability constants (Kp) was 2.4. Using the definitions suggested by Marzulli et al. (1969) Toxicol. Appl. Pharmacol. Suppl. 3, 76-83, HQ would be classified as 'slow' with respect to its absorption through human stratum corneum.
mesh_terms: D000818:Animals; D006801:Humans; D006873:Hydroquinones / Q000493:pharmacokinetics* / Q000633:toxicity; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D010781:Photography; D051381:Rats; D011916:Rats, Inbred F344; D012867:Skin / Q000187:drug effects; D012869:Skin Absorption; D012996:Solutions
chemical_list: D006873:Hydroquinones; D012996:Solutions; C031927:hydroquinone