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Review of Biological Monitoring Tests for Toluene.

Lowry LK
Biological Monitoring of Exposure to Chemicals, Organic Compounds 1987:99-109
Biological tests for monitoring toluene (108883) exposure were reviewed including hippuric-acid (495692) in urine, toluene in blood and toluene in alveolar air. The physical properties of toluene in relation to its biological toxicity were described, and the principal metabolic pathways for toluene in humans were outlined. Recommended methods for measuring hippuric-acid in urine were discussed, including high performance liquid chromatography, gas chromatography after silyl or diazomethane derivatization, and isotachophoresis. Timing of urine samples and methods of storage of samples prior to analysis were discussed. The need to take into account the presence of hippuric-acid in urine as a result of dietary intake was considered, as well as the possibility of chemical interference. The controversy relating to methods of reporting hippuric-acid concentrations in urine was discussed. Gas chromatography is the most common method for measuring toluene levels in blood and alveolar air. Toluene has not normally been found to be present in the blood or alveolar air of humans, and no chemical interferences have been described for the recommended methods of toluene determination. The possibility of nonoccupational exposure resulting in elevated blood or alveolar air toluene levels was discussed. The authors note that blood toluene levels are more sensitive indices of toluene exposure than urine hippuric-acid levels. The American Conference of Government Industrial Hygienists recommendations for the monitoring of toluene exposure were summarized.
Biological-monitoring; Organic-solvents; Toluenes; Occupational-exposure; Biochemical-analysis; Analytical-methods; Sampling-methods; Chromatographic-analysis;
108-88-3; 495-69-2;
Publication Date
Ho MH; Dillon HK;
Fiscal Year
Source Name
Biological Monitoring of Exposure to Chemicals, Organic Compounds
Page last reviewed: February 11, 2022
Content source: National Institute for Occupational Safety and Health Education and Information Division