Correlation of Urinary Bisphenol A and Phthalates With Overweight and Obesity in Children

Background Bisphenol A (BPA) and phthalates are endocrine-disrupting chemicals widely used in plastics, food packaging, and consumer goods. These compounds may contribute to childhood obesity by interfering with hormonal regulation and metabolic pathways. Objective This study aimed to evaluate urinary BPA and phthalate concentrations in normal-weight and overweight or obese children and to assess correlations with anthropometric measures. Methods A prospective observational study was conducted in the Department of Pediatrics, M. S. Ramaiah Medical College, Bangalore, India, from September 2023 to March 2025. Ninety children aged 2-18 years were enrolled: 45 overweight or obese (cases) and 45 age- and sex-matched normal-weight controls. Anthropometric parameters, including height, weight, body mass index, waist circumference, hip circumference, waist-to-hip ratio, and triceps skinfold thickness, were measured. Midstream urine samples were collected and analyzed for BPA and phthalates using a double-antibody sandwich enzyme-linked immunosorbent assay. Creatinine correction was performed. Statistical analysis included independent t-tests, chi-squared tests, and Pearson's correlation coefficients. Results Mean urinary BPA levels were significantly higher in overweight or obese children (4.59 ± 1.23 ng/mL) compared with controls (1.57 ± 0.48 ng/mL; t = 13.6; p < 0.001). Mean urinary phthalates were also elevated in cases (230.90 ± 35.30 ng/mL) versus controls (100.30 ± 18.70 ng/mL; t = 19.4; p < 0.001). Raw urinary BPA and phthalate levels demonstrated positive correlations with body mass index, waist circumference, and triceps skinfold thickness. Interestingly, creatinine-corrected BPA and phthalate levels were higher in cases. Conclusion Urinary BPA and phthalate concentrations were significantly associated with overweight and obesity in Indian children. These findings support the role of endocrine-disrupting chemicals as potential obesogens and highlight the need for public health strategies to reduce pediatric exposure to plastics.