Effect of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children.

Abstract

Objective: To investigate the influence of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children.

Materials and methods: A group of 217 children three to six years of age from a rural area were given a thorough physical examination and the concentration of lead in blood samples taken from each subject was determined. The indices of lymphocyte immunity (CD+3CD+4, CD+3CD+8, CD+4CD+8, CD-3CD+19) and erythrocyte immunity (RBC-C3b, RBC-IC, RFER, RFIR, CD35 and its average fluorescence intensity) of 40 children with blood lead levels above 0.483 micromol/L were measured and compared with a control group.

Results: The blood lead levels of the 217 children ranged from 0.11 micromol/L to 2.11 micromol/L. The CD+3CD+4 and CD+4CD+8 cells were lower (P<0.01) and the CD+3CD+8 cells were higher in the lead-poisoned subjects than those in the control group (P<0.05). CD+3 and CD-3CD+19 did not show significant differences. Although the RBC-C3b rosette forming rate was lower and the RBC-IC rosette forming rate was higher in the lead-poisoned group, this difference could not be shown to be statistically significant (P>0.05). RFIR was found to be lower in the lead-poisoned group (P<0.01). Compared with the control group, the positive rate of CD35 was not found to be significantly different in a group of 25 lead-poisoned children (P>0.05), while the average fluorescence intensity was lower in the lead-poisoned group (P<0.05).

Conclusion: Lead exposure can result in impaired immune function of T lymphocytes and erythrocytes in preschool children.