[en] Serum immunoglobulin (IgG, IgM, and IgE) concentrations of 38 preschool children with blood lead levels ≥0.48 μmol/L (10 μg/dL) were examined and compared to 35 preschool children with blood lead levels ≤0.48 μmol/L. No differences in serum concentrations of IgG, IgM, and IgE in the populations were observed, but IgG, IgM, and IgE of male and female children from the high blood lead level group were compared to those of controls and the results showed that IgG and IgM were significantly lower in the high blood lead level group of females than in the controls, while IgE was significantly higher in the high blood lead level group of females than in the controls (P<0.05). No correlation between blood lead concentration and serum immunogloblins IgG and IgM was demonstrated, but a statistically significant relationship between IgE and blood lead level was found in this population. These data indicate that the effect of lead on IgG, IgM, and IgE was stronger in females than in males and lead could play a role in this process by stimulating IgE production