Preparation of Standard for Biological Monitoring of Organic Solvent

Abstract

Artificial urines containing major components of human urine, as ingredients, were prepared as specimens for the survey of quality control. The hippuric acid, m- methylhippuric acid and mandelic acid of various concentrations were spiked into the artificial urines. Thereafter, the specimens were kept at 30°C, 1°c and - 20°C for 1, 2 and 4weeks, and change in concentrations during storage was examined by high performance liquid chromatography. The ratio of the concentrations of the three acids after storage to those before storage was about 99 per cent or above under the storage condition at 1°c for 2weeks and - 20°C for 4weeks. Creatinine was more unstable than the three acids under these storing condition at 30°C and 1°C. The metabolites were more stable when they were kept in lower temperatures.