Quantitative analysis of catechol and 4-methylcatechol in human urine.
A method was developed for the quantitative analysis of catechol and 4-methylcatechol in human urine. [U-14C]Catechol was used as in internal standard. Urine was treated with beta-glucuronidase and sulphatase, acidified and extracted with ether. The ether extract was silylated and analysed by glass capillary gas chromatography. Catechol and 4-methylcatechol occurred in urine primarily as conjugates. Levels of catechol and 4-methylcatechol in the urine of nonsmokers on unrestricted diets were 10 +/- 7.3 (mean +/- 1 SD) and 3.4 +/- 2.3 mg/24 hr, respectively. Nonsmokers on uniform restricted diets, in which the intake of plant-derived products was limited, excreted 4.4 +/- 1.2 mg catechol and 8.1 +/- 1.7 mg 4-methylcatechol/24 hr. Smokers on the same restricted diet excreted 6.8 +/- 3.0 mg catechol and 6.1 +/- 2.6 mg 4-methylcatechol/24 hr. These results indicate that diet is a major factor in determining urinary catechol levels and that the contribution of smoking is comparatively small. Catechol and 4-methylcatechol appear to have different dietary precursors.
D000328:Adult; D002396:Catechols / Q000652:urine*; D002849:Chromatography, Gas; D006801:Humans; D008297:Male; D008875:Middle Aged; D012907:Smoking
D002396:Catechols; C018599:4-methylcatechol