Summary
Nested case-control study (N = 291; 97 CHD cases, 194 controls, 1:2 ratio) within a maternal-infant cohort in Lanzhou, Gansu Province, northwestern China (a mining-affected urban region). Maternal peripheral blood Sb was measured during pregnancy. The study found a statistically significant association between elevated maternal blood Sb and CHD risk in offspring, particularly isolated CHDs, with an approximately 4.5-fold higher risk in the high-Sb group and a threshold-like dose-response pattern above approximately 18 microg/L blood Sb.
Key numbers
Maternal blood Sb (microg/L), whole blood, during pregnancy (Table 2):
| Group | Mean | P25 | Median | P75 |
|---|---|---|---|---|
| Control (n = 194) | 13.05 | 8.80 | 11.97 | 16.75 |
| All CHDs (n = 97) | 20.30 | 9.02 | 14.05 | 20.30 |
| Isolated CHDs | 19.50 | 10.30 | 16.84 | 23.52 |
| Multiple CHDs | 20.93 | 8.13 | 13.32 | 20.30 |
Odds ratios (high vs. low Sb exposure group, adjusted model):
- All CHDs: OR = 4.456 (95% CI 2.829-9.782)
- Isolated CHDs: OR = 12.648 (95% CI 2.806-56.953), p = 0.003
- Multiple CHDs: OR = 2.986 (95% CI 0.928-9.610), p = 0.068 (not significant)
- Septal defects: OR = 4.649 (95% CI 1.001-12.857)
- ASDs: OR = 3.492 (95% CI 1.061-11.206)
Per 6 microg/L increment in blood Sb:
- All CHDs: OR = 1.389 (95% CI 1.110-1.735)
- Isolated CHDs: OR = 2.106 (95% CI 1.250-3.556)
Threshold: Restricted cubic spline analysis showed a non-linear association with elevated CHD risk apparent above approximately 18.409 microg/L blood Sb (the high-exposure group boundary derived from the control distribution). This is a population-derived percentile, not a regulatory or clinical threshold.
Study region: Gansu Provincial Maternity and Child-Care Hospital, Lanzhou, northwestern China; urban area of a mining region. Industrial and electronic waste Sb sources prominent in this area.
Evidence Fitness
Modeled or limited evidence for CHD associations. The case-control design is appropriate for rare outcomes; sample size is moderate (N = 291). Confounders including pre-pregnancy BMI, gestational weight gain, smoking, hypertension, folic acid supplementation, and mineral supplement use were adjusted for. The study population is from a mining-affected area with elevated baseline Sb exposure, limiting generalizability to lower-exposure populations. No food-specific Sb source was identified.
Methods (brief)
Nested case-control within a birth cohort, Lanzhou, 2021-2024. Maternal peripheral blood collected during pregnancy; Sb measured by ICP-MS. CHDs diagnosed by postnatal echocardiography. Logistic regression; restricted cubic spline analysis.
Implications
- Certification: provides evidence of a possible developmental endpoint (cardiac malformation) for Sb at blood concentrations that exceed typical background by approximately 50%.
- Courses: illustrates that developmental endpoints may be more sensitive than adult chronic endpoints for Sb.
- App: not directly applicable to food contamination profiles; this is a biomonitoring study.
- Microbiome: not addressed.
Provenance notes
Open access, CC BY. No DOI resolved at deposit time (PMC13724518); DOI per paper: 10.3389/fpubh.2026.1957018. File from PMC OA S3.
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