Toluene is known to be the most popular solvent for industrial use,1,2) and attention has been paid on the possibility of biological monitoring of toluene exposure by urinalysis for metabolites such as hippuric acid and o-creso1.3-5) In a previous study6) on possible ethnic difference in toluene metabolism, it was disclosed that Chinese toluene workers excrete less hippuric acid in urine than t...

Enantiopure sulfoxides are valuable asymmetric starting materials and are important chiral auxiliaries in organic synthesis. Toluene monooxygenases (TMOs) have been shown previously to catalyze regioselective hydroxylation of substituted benzenes and phenols. Here we show that TMOs are also capable of performing enantioselective oxidation reactions of aromatic sulfides. Mutagenesis of position ...

Biotransformations of a series of ortho-, meta- and para-substituted ethylbenzene and propylbenzene substrates have been carried out, using Pseudomonas putida UV4, a source of toluene dioxygenase (TDO). The ortho- and para-substituted alkylbenzene substrates yielded, exclusively, the corresponding enantiopure cis-dihydrodiols of the same absolute configuration. However, the meta isomers, genera...

Intake of foods and drinks containing benzoic acid influences the urinary hippuric acid (HA) concentration, which is used to monitor toluene exposure in Japan. Therefore, it is necessary to control the intake of benzoic acid before urine collection. Recently, some reports have suggested that components of coffee, such as chlorogenic, caffeic, and quinic acids are metabolized to HA. In this stud...

The separation of hippuric and m-methylhippuric acid as toluene and m-xylene metabolites present in urine of people exposed simultaneously to toluene and xylene is described. Chloroform was used for hippuric and m-methylhippuric acid extraction. Satisfactory separation of these metabolites was obtained on TLC plates covered with silica gels and developed in chloroform acetic acid-water (4:1:1);...

Exposure monitoring by personal diffusive samplers, biological monitoring of toluene exposure by urinary hippuric acid determination, haematology, serum biochemistry for liver function, and a subjective symptom survey by questionnaire were conducted on 303 male solvent workers. They were exposed to a mixture of solvents including toluene (geometric mean 18 ppm), methyl ethyl ketone (MEK; 16 ppm...

To better understand precursors of dicarboxylic acids in ambient secondary organic aerosol (SOA), we studied C4–C9 present SOA formed from the oxidation toluene, naphthalene, α-pinene, and isoprene. were analyzed by offline derivatization gas chromatography–mass spectrometry. We revealed that C4 including succinic acid, maleic fumaric malic DL-tartaric meso-tartaric acid are produced photooxida...