Imported occupational lead poisoning: report of four cases

Background: In most industrialized countries, occupational lead poisoning has become increasingly rare, however this metal remains a serious health hazard in the rest of the world. Report of cases: We observed four male patients (aged 35 divided by 54 years) who had suffered recurrent abdominal pain due to recent lead exposure (for 7 to 13 months) in two Chinese battery recycling plants. On their return to Italy, three of them presented normocytic, normochromic anaemia. The diagnosis was confirmed by high lead levels in the blood and urine, decreased erythrocyte delta- aminolevulinic acid dehydratase (ALA-D), raised erythrocyte zinc protoporphyrin (ZP), and elevated urinary excretion of delta-aminolevulinic acid (ALA-U) and porphyrins. Chelation with EDTA resulted in increased urinary lead excretion, improvement of the clinical picture, decreased ZP, and progressive normalization of the other lead biomarkers (Pb-B, ALA-D, ALA-U, urinary porphyrins). Conclusions: Temporary work in developing countries may result in imported lead poisoning. Differential diagnosis of this unusual condition requires careful medical history collection and specific toxicological analysis. Preventive measures for workers going abroad are needed.