Background: Toxicological studies indicate that polybrominated diphenyl ethers (PBDEs), a class of flame retardants, may impair kidney function through oxidative stress. However, epidemiological evidence, especially for exposure occurring during gestation remains limited.

Objective: To investigate the association between prenatal PBDEs and kidney function in adolescents at age 12 years.

Methods: We used data from the Health Outcomes and Measures of the Environment (HOME) Study, a prospective pregnancy and birth cohort (2003-2006; Cincinnati, OH, USA). We used multivariable linear regression models adjusted for sociodemographic characteristics, pregnancy health behaviors, and reproductive history to estimate associations between log10-transformed PBDE concentrations (ng/g lipid) in maternal serum at 16 weeks’ gestation with natural log-transformed adolescent kidney markers, including serum creatinine, cystatin C, urinary albumin, and estimated glomerular filtration rate (eGFR). We used modified Poisson regression to estimate associations between PBDEs with albumin-creatinine ratio (ACR). Effect measure modification by sex was evaluated using interaction terms.

Results: Higher prenatal BDE-28 concentrations were associated with lower ACR (β=-0.52; 95% CI=-0.92, -0.12), lower serum creatinine (β=0.12; 95% CI=-0.22, -0.03), and higher eGFR (β=0.12; 95% CI=0.02, 0.21). BDE-153 was also associated with lower serum creatinine (β=-0.08, 95% CI=-0.16, -0.005), while BDE-47 was associated with higher eGFR (β=0.08, 95% CI=0.004, 0.16). Poisson regression showed inverse associations between several PBDEs and elevated ACR. Evidence of effect measure modification by sex was observed with eGFR for BDE-47(pint=0.061), BDE-99 (pint=0.135), BDE-100 (pint=0.078), and BDE-153 (pint=0.026), with statistically insignificant inverse associations in males and positive associations in females.

Conclusion: Prenatal PBDE exposure was inversely associated with ACR and creatinine but positively associated with eGFR in adolescents. Although these findings indicate better kidney function, they may reflect early subclinical physiological adaptation rather than protection, highlighting the importance of developmental timing and compensatory renal responses.