Optimized Liquid-Chromatographic Method for Fluorometric Determination of Urinary-AminoIevuIinic Acid in Workers Exposed to Lead

We developed a fluorometric method for determining S-aminolevulinic acid (ALA) in urine of lead workers. A high-performance liquid chromatograph (HPLC) equipped with a fluorescence HPLC monitor is used. The detection limit for aqueous ALA is 20 g/L (15 pmol of ALA in the 100-L sample). The working linear range of urinary ALA concentra-tion was 0.1 to 100 mg/L. In 25 lead-exposed workers, ALA values by the present method for urine correlated well with those obtained by a conventional colorimetric method (r = 0.996). The advantage of the present method for micro-determination of urinary ALA is its high sensitivity. AdditIonal Keyphrases: monitoring toxicology environmental hazards colorimetry compared The concentration of &-aminolevulinic acid (ALA) in urine has been widely used as a measure of the biological effect o