Association between Urinary 3-Phenoxybenzoic Acid and Body Mass Index in Korean adults : 1st Korean National Environmental Health Survey

Abstract

Objective: We investigated the association between pyrethroid exposure and obesity in a national representative cross-sectional study. In addition, we evaluated the differences in the association between pyrethroid exposure and obesity depending on the exposure levels. Method:We used data of 3,671 participants aged above 19 from the Korean National 1 Environmental Health Survey in 2009-2011. In our analysis, multivariate piece-wise regression and logistic regression analysis were used to investigate the association between urinary 3-PBA (3-Phenoxybenzoic Acid) and BMI. Result: Log-transformed level of urinary 3-PBA had significantly positive association with BMI at the low-level range of exposure (p<0.0001), and opposite associations were observed at the high level exposure (p=0.04) after adjusting covariates. In piece-wise regression analysis, the flexion point that changes direction of the associations was at around 4 ug/g creatinine of urinary 3-PBA. As quintiles based on concentration of urinary 3-PBA increased to Q4, the ORs for prevalence of overweight (BMI ≥ 23kg/m2) were increased, and the OR of Q5 was lower than that of Q4 (OR = 1.810 for Q4

OR = 1.483 for Q5). In the analysis using obesity (BMI ≥ 25kg/m2) as outcome variable, significant associations were observed between obesity and quintiles of 3-PBA, however, there were no differences between the OR of Q5 and that of Q4 (OR = 1.659 for Q4

OR = 1.666 for Q5). Conclusion: Our analysis suggested that low-level of pyrethroid exposure has positive association with BMI, however, there is an inverse relationship above the urinary 3-PBA level at 4 ug/g creatinine.