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

Yunhui Zhang; Xiangzhou Meng; Li Chen; Dan Li; Lifang Zhao; Yan Zhao; Luxi Li; Huijing Shi

doi:10.1371/journal.pone.0104852

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

PLoS One. 2014 Aug 14;9(8):e104852. doi: 10.1371/journal.pone.0104852. eCollection 2014.

Authors

Yunhui Zhang¹, Xiangzhou Meng², Li Chen¹, Dan Li³, Lifang Zhao², Yan Zhao¹, Luxi Li¹, Huijing Shi³

Affiliations

¹ Department of Environment Health, School of Public Health/Key Laboratory of Public Health Safety of Chinese Ministry of Education, Fudan University, Shanghai, China.
² State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China.
³ Department of Maternal, Child and Adolescent Health, School of Public Health/Key Laboratory of Public Health Safety of Chinese Ministry of Education, Fudan University, Shanghai, China.

Abstract

Objective: 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.

Materials and methods: 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.

Results: 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.

Conclusion: 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) were significantly higher than those in elder 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 <10 years of age.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Body Mass Index
Child
China
Environmental Exposure*
Female
Humans
Male
Obesity / chemically induced*
Phthalic Acids / toxicity*
Puberty*

Substances

Phthalic Acids