Cross-sectional study of blood lead effects on iron status in Korean lead workers

Objective This study assessed the iron status of Korean male lead workers by measuring the dietary iron intake and biochemical indices, and tested the hypothesis that a high blood lead level is associated with impaired iron function, which results in higher prevalence of iron deficiency when the route of exposure is not the gastrointestinal tract. Methods One hundred eighteen lead workers and 42 non–lead workers were recruited from mandatory annual health surveillance sites for industrial workers. Blood lead, hemoglobin, and hematocrit levels were evaluated as hematologic parameters, and serum iron concentrations, total iron-binding capacity, and percentage of transferrin saturation were evaluated as iron-status parameters. Dietary iron intake was assessed by a 24-h recall method. Results Lead workers had significantly lower hemoglobin, hematocrit, serum iron levels, percentage of transferrin saturation, and dietary iron intake than did non–lead workers, and they had significantly higher (P < 0.01) total iron-binding capacity. The occurrence of iron-deficiency cases, as assessed by hematocrit values, was significantly higher (P < 0.001) in lead workers than in non–lead workers, and the prevalence of iron deficiency was associated with high blood lead levels (P = 0.033). The dietary iron intake was inversely associated with zinc protoporphyrin (P = 0.032). Conclusions This study confirmed the adverse effects of high blood lead levels on hematologic pathways and the effectiveness of dietary iron intake as a secondary preventive intervention against lead toxicity. To promote health and to prevent toxic effects of lead exposure in Korean lead workers, an adequate intake of dietary iron is strongly recommended.