Abstract
The main metabolites of o-xylene in urine are o-methylhippuric acid, o-toluic acid, o-toluic acid glucuronide, 3,4-dimethylphenol, 3,4-dimethylphenol conjugates and o-xylylmercapturic acid. The urinary excretion of o-toluic acid, o-toluic acid conjugates and o-xylene were increased by the prior administration of sodium benzoate. Conversely, the amounts of o-methylhippuric acid, 3,4-dimethylphenol conjugates and o-xylylmercapturic acid decreased by sodium benzoate pretreatment. In addition, the urinary excretion of o-methylhippuric acid was delayed by the pretreatment. The percentages of urinary excretion of the o-xylene metabolites were substantially changed by the pretreatment with sodium benzoate. These results therefore highlight a potential interaction of an air pollutant with a food additive, an interaction that remains to be established in man.