Environmental lead exposure, anaemia, and early childhood stimulation among children in Bangladesh: Evidence from the MICS 2025

Background Environmental lead exposure, anaemia, and inadequate early childhood stimulation are important dimensions of child vulnerability. However, nationally representative evidence in Bangladesh is limited. This study examined blood lead levels (BLLs), their correlates, associations with anaemia and haemoglobin, and factors associated with early childhood stimulation. Methods We analysed nationally representative, cross-sectional data from the Bangladesh Multiple Indicator Cluster Survey (MICS) 2025. Biomarker analyses included children aged 12–59 months with valid measurements, while stimulation analyses included children aged 24–59 months. Elevated BLL was defined as ≥5 μg/dL. Survey-weighted modified Poisson and linear regression assessed associations with anaemia and haemoglobin, respectively. Restricted cubic splines examined non-linear relationships. Results Among 10,622 children, the weighted mean BLL was 5.21 ± 3.77 μg/dL, and 38.5% had elevated BLLs. Elevated BLL was associated with male sex (aPR 1.13), indoor smoking (1.08), nearby battery-related activity (1.10), e-waste activity (1.16), urban residence (1.20), and higher household wealth; maternal education showed an inverse gradient. BLL ≥5 μg/dL was not significantly associated with anaemia (aPR 0.98; 95% CI 0.92–1.04) or haemoglobin (β 0.01; 95% CI −0.06 to 0.07). BLL ≥10 μg/dL was also not significantly associated with haemoglobin after full adjustment (β −0.10; 95% CI −0.23 to 0.04). Spline models indicated non-linearity, with the lowest anaemia prevalence around 4–5 μg/dL. Stimulation practices were associated with maternal education, household wealth, and stunting. Conclusion Lead exposure and developmental environments are socially patterned among Bangladeshi children. Integrated environmental, nutritional, socioeconomic, responsive-caregiving interventions are warranted, with lead exposure assessed independently of anaemia and haemoglobin.