Age and sex-specific relationships between phthalate exposures and obesity in Chinese children at puberty

• Published in: PloS one 2014-08, Vol.9 (8), p.e104852
• Main Authors: Zhang, Yunhui, Meng, Xiangzhou, Chen, Li, Li, Dan, Zhao, Lifang, Zhao, Yan, Li, Luxi, Shi, Huijing
• Format: Article
• Language: English
• Subjects: Adolescent; Age; Anthropometry; Biology and Life Sciences; Body fat; Body mass; Body Mass Index; Body size; Body weight; Cardiovascular disease; Child; Child health; Childhood obesity; Children; China; Dioctyl phthalate; Ecology and Environmental Sciences; Environmental Exposure; Esters; Exposure; Female; Girls; Health risk assessment; Humans; Male; Mass spectrometry; Medicine and Health Sciences; Metabolites; Obesity; Obesity - chemically induced; Overweight; Phthalates; Phthalic Acids - toxicity; Puberty; Quadrupoles; Regression analysis; Sex; Students; Studies; Urine
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0104852

To examine the age and sex-specific associations of urine levels of six mono-phthalates with body size and fat distribution in Chinese children at puberty. Four hundred and ninety-three school-aged children (247 boys, 246 girls) were recruited. Obesity related anthropometric indices were measured and body fat proportion (BF%) was calculated. Spot urine samples were collected and phthalate monoesters were detected by an API 2000 electrospray triple quadrupole mass spectrometer (ESI-MS/MS). Associations between phthalate exposure and overweight/obesity measures and their trends were examined by multiple linear regression and Logistic regression analyses, respectively. Di-2-ethylhexyl phthalate (DEHP) metabolites and monobutyl phthalate (MBP) were found to be the most detectable chemicals. In 8-10 years (yrs) group, concentrations of MEHP and MBP were significantly higher in girls than those in boys. However, concentrations of all phthalate monoesters, except for MEP and MEHP, in 11-13 yrs boys were significantly higher than those in girls. After adjusting for confounders including puberty onset, urinary concentrations of MBP and sum of low molecular-weight phthalate metabolites (∑LMP) were positively associated with boys' obesity in a concentration-effect manner, while concentrations of MEHP, MEHHP and sum of DEHP metabolites (∑MEHP) were negatively associated with girls' obesity. Associations between phthalate exposure levels and BMI z-score changes were age- and sex-specific in school-age children. There are age and sex-specific concentration-effect associations between phthalate exposure and fat distribution in Chinese children. Urinary phthalate levels in 11-13 yrs boys were about 30 percent higher than those in girls, and ∑MEHP levels in younger boys (10 yrs). Associations were positive for MBP and ∑LMP with both BMI z-score and fat distribution in boys >10 years of age, and negative for ∑MEHP with fat distribution in girls