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Prenatal polybrominated diphenyl ethers exposure and anogenital distance in boys from a Shanghai birth cohort
Min Luan1, Hong Liang1, Fen Yang1
1NHC Key Lab. of Reproduction Regulation (Shanghai Institute of Planned Parenthood Research), School of Public Health, Fudan University, Shanghai, China.
Insights
Prenatal exposure to polybrominated diphenyl ethers (PBDEs) may shorten anogenital distance (AGD) in infant boys. This suggests potential adverse effects on male reproductive development from environmental PBDE exposure.
Area of Science:
- Environmental Health
- Reproductive Toxicology
- Pediatric Endocrinology
Background:
- Polybrominated diphenyl ethers (PBDEs) are flame retardants with endocrine-disrupting properties.
- Previous studies suggest prenatal PBDE exposure may negatively impact anogenital distance (AGD), a marker of prenatal androgen exposure.
Purpose of the Study:
- To investigate the association between prenatal PBDE exposure and AGD in male infants aged 0-4 years.
- To assess the impact of specific PBDE congeners on male reproductive development markers.
Main Methods:
- Analysis of nine PBDE congeners in cord plasma from 192 male infants in the Shanghai-Minhang Birth Cohort Study (S-MBCS).
- Measurement of anopenile (AGD_AP) and anoscrotal (AGD_AS) distances at birth, 6, 12, and 48 months.
- Statistical analysis using multiple linear regression and generalized estimating equation (GEE) models.
Main Results:
- Higher quartiles of BDE-47 and Σ4PBDEs (sum of BDE-47, BDE-99, BDE-100, BDE-153) were associated with shorter AGD_AP and AGD_AS.
- Significant inverse associations were observed between AGD_AS and BDE-47/Σ4PBDEs in higher quartiles at 12 and 48 months.
- GEE models corroborated the inverse association between BDE-47 and AGD_AS.
Conclusions:
- Prenatal exposure to BDE-47 and Σ4PBDEs, even at low levels, may be linked to reduced AGD in boys.
- This suggests potential adverse effects of PBDEs on male reproductive development.
- Further research is needed to confirm these preliminary findings.
Background:
Polybrominated diphenyl ethers (PBDEs) are major brominated flame retardant (BFR) chemicals with endocrine-disrupting properties. One small-scale study on humans has suggested that prenatal exposure to PBDEs is adversely related to anogenital distance (AGD) a sensitive marker for prenatal androgen exposure. The aim of the present study was to examine the associations between prenatal exposure to PBDEs and AGD among boys 0-4 years of age in a cohort study.
Methods:
In the Shanghai-Minhang Birth Cohort Study (S-MBCS), nine PBDE congeners were measured in cord plasma of 192 male infants. We measured anopenile distance (AGDAP) and anoscrotal distance (AGDAS) at birth, 6 months, 12 months, and 48 months of age. A total of 190 boys with neonatal concentrations of PBDEs (ng/g lipid) who had at-least one AGD measurement were included in our study. Information on potential confounding variables were collected through in-person interviews. Multiple linear regression models and generalized estimating equation (GEE) models were used to evaluate the associations between prenatal PBDEs concentrations and AGD.
Results:
Among the nine congeners, BDE-47 had the highest detection rate (83.68%) and the highest median concentration (0.18 ng/g lipid). Boys who had neonatal concentration of BDE-47 or Σ4PBDEs (sum of BDE-47, BDE-99, BDE-100, and BDE-153) in the higher quartile generally had shorter AGDAP and AGDAS than those in the first quartile. Significant inverse associations were found between AGDAS and fourth quartile BDE-47 levels among boys 12 months and 48 months of age (β = -5.57, 95% confidence interval (CI): -9.89, -1.25 for 12 month of age; β = -4.32, 95% CI: -8.18, -0.46 for 48 month of age). Inverse associations were also observed between AGDAS and fourth quartile Σ4PBDEs levels among boys 12 months of age (β = -5.13, 95% CI: -9.89, -1.25). In GEE models, similar patterns of association were also observed between BDE-47 and AGDAS.
Conclusions:
Our findings provide preliminary evidence that prenatal exposure to BDE-47 and Σ4PBDEs, even at low environmental levels, may be associated with shorter AGD in boys. This data suggest that prenatal exposure to PBDEs may have adverse effects on male reproductive development. Further studies should be conducted to validate these results.
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