Limites de aplicabilidade da determinação do ácido delta-aminolevulínico urinário como teste screening na avaliação da intoxicação profissional pelo chumbo Applicability limits of urinary delta-aminolevulinic acid as a screening test to evaluate professional intoxication by lead

Abstract

A aplicabilidade da determinação da concentração do ácido delta-aminolevulínico urinário (ALA-U) no controle da saúde de trabalhadores expostos ocupacionalmente ao chumbo foi realizada em dois grupos de trabalhadores. Os valores médios de Pb-S para os dois grupos foram 17,3 µg/dl (6,2-39,4) e 61,5 µg/dl (41,1-91,0), respectivamente. As concentrações de ALA-U foram determinadas por HPLC e por espectrofotometria. Uma correlação significativa (pThe relationship between concentrations of ALA-U and Pb-S for two groups of workers is reported. The first group consisted of workers from a telephone company, and the second, of workers from battery factories with average Pb-S equivalent to 17,3 µg/dl (6,2-39,4) and 61,5 µg/dl (41,1-91,0), respectively. The aim of this study was to evaluate the utilization of ALA-U levels as a screening test for different levels of lead in blood by means of High Performance Liquid Chromatography (HPLC) and of spectrophotometry. A significant correlation was found between measured ALA and levels of blood lead (R = 0,739 - first group; R = 0,902 - second group; p < 0,001). The validity of ALA-U test to evaluate different levels of lead in blood was also studied. By using ALA levels of 3 mg/g creatinine as a threshold to detect levels of lead in blood equal to or higher than 20 µg/dl, the test results, for the workers in the first group, showed sensitivity of 92% and specificity of 90%. In both groups, the false positives as well as the false negatives were lower than 10%, which was enough to validate the test.

Keywords

• Intoxicação por Chumbo
• Ácido Aminolevulínico
• Exposição Ocupacional
• Saúde Ocupacional
• Lead Poisoning
• Aminolevulinic Acid
• Occupational Exposure
• Occupational Health