PT  - JOURNAL ARTICLE
AU  - C S Okereke
AU  - A M Kadry
AU  - M S Abdel-Rahman
AU  - R A Davis
AU  - M A Friedman
TI  - Metabolism of benzophenone-3 in rats.
DP  - 1993 Sep 01
TA  - Drug Metabolism and Disposition
PG  - 788--791
VI  - 21
IP  - 5
4099  - http://dmd.aspetjournals.org/content/21/5/788.short
4100  - http://dmd.aspetjournals.org/content/21/5/788.full
SO  - Drug Metab Dispos1993 Sep 01; 21
AB  - Benzophenone-3 [2-hydroxy-4-methoxybenzophenone (HMB), oxybenzone, Spectra-Sorb UV-9 light absorber] is used in many cosmetics and sunscreens as a UV absorber. This study was conducted to investigate the metabolism of HMB (100 mg/kg body weight administered orally). 2,4-Dihydroxybenzophenone (DHB), 2,2'-dihydroxy-4-methoxybenzophenone (DHMB), and 2,3,4-trihydroxy-benzophenone (THB) metabolites were identified as free and conjugated forms by HPLC analysis. HMB was rapidly absorbed, metabolized, and detected in plasma (as free and protein bound) at 5 min postadministration. The parent compound and metabolites (free and conjugated) were detected at 6 hr in most tissues. DHB was present in most tissues with the highest concentration in the liver. DHMB was only detected as the conjugated form in liver, spleen, and heart. Trace amounts of THB were also detected in biological samples. Urine was the primary route, whereas feces was the secondary route of elimination of HMB and its metabolites. This study revealed O-dealkylation as the major pathway of HMB metabolism.