title: Association between urinary 3-phenoxybenzoic acid and body mass index in Korean adults: 1(st) Korean National Environmental Health Survey.
abstract: BACKGROUND
  According to US-EPA report, the use of pyrethrins and pyrethroids has increased during the past decade, and their area of use included not only in agricultural settings, but in commerce, and individual household. It is known that urinary 3-PBA, major metabolite of pyrethroid, have some associations with health effect in nervous and endocrine system, however, there's no known evidence that urinary 3-PBA have associations with obesity.
  
  
  METHODS
  We used data of 3671 participants aged above 19 from the Korean National 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.
  
  
  RESULTS
  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 ≥ 23 kg/m(2)) 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 ≥ 25 kg/m(2)) 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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Minsang
authors.initials: M
authors.lastname: Yoo
authors.affiliation: Environmental Health Center, Seoul National University College of Medicine, Seoul, Republic of Korea ; Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
authors.forename: Youn-Hee
authors.initials: YH
authors.lastname: Lim
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Taeshik
authors.initials: T
authors.lastname: Kim
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Dongwook
authors.initials: D
authors.lastname: Lee
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea ; Environmental Health Center, Seoul National University College of Medicine, Seoul, Republic of Korea ; Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
authors.forename: Yun-Chul
authors.initials: YC
authors.lastname: Hong
keywords: 3-phenoxybenzoic acid; BMI; KNEHS; Obesity; Overweight; Pyrethroid