Objective Guiyu is the major electronic-waste (e-waste) recycling town in China. This study was to measure the effect of e-waste exposure on the synthesis of haemoglobin (Hb) in preschool children.

Methods 222 children lived at Guiyu town and 204 children lived in a no e-waste polluted town were chosen to test their blood lead, Hb, ferritin, folate, vitamin B₁₂ levels and hemoglobinopathy, then fill the self-questionnaires by their parents.

Results There were no significant differences in the levels of ferritin, folate, vitamin B₁₂ between exposure and control groups, and all children had been excluded thalassemia. The blood lead levels (BLLs) and rate of BLLs ≥ 10 ug/dL in exposure group were signifcantly higher than that in control group (all p < 0.01). Three groups were divided according to BLLs (Group A: <5.0 ug/dL, Group B: 5.0–9.9 ug/dL, Group C: ≥10.0 ug/dL). It can be seen that the levels of Hb were decreased along with elevated BLLs significantly in exposure group (F = 3.52, p = 0.03), however, not shown in control group (F = 1.98, p = 0.14). Furthermore, the prevalence rate of anaemia along with BLLs ≥10 ug/dL in exposure group was significant higher than that in control group (4.0% vs. 0.5%, p < 0.05), and the prevalence rate of anaemia without BLLs ≥10 ug/dL and iron deficiency in exposure group was significant higher than that in control group (6.5% vs. 2.0%, p < 0.05).

Conclusion Different from the general environment, the lead exposure in e-waste area might aggravate the inhibition of synthesis of Hb, and other potential e-waste toxicants might also have a responsibility for it.