title: Analysis of human hair to assess exposure to organophosphate flame retardants: Influence of hair segments and gender differences.
abstract: Hair is a promising, non-invasive, human biomonitoring matrix that can provide insight into retrospective and integral exposure to organic pollutants. In the present study, we measured the concentrations of organophosphate flame retardants (PFRs) in hair and serum samples from university students in Guangzhou, China, and compared the PFR concentrations in the female hair segments using paired distal (5~10cm from the root) and proximal (0~5cm from the root) samples. PFRs were not detected in the serum samples. All PFRs except tricresyl phosphate (TMPP) and tri-n-propyl phosphate (TPP) were detected in more than half of all hair samples. The concentrations of total PFRs varied from 10.1 to 604ng/g, with a median of 148ng/g. Tris(chloroisopropyl) phosphate (TCIPP) and tri(2-ethylexyl) phosphate (TEHP) were the predominant PFRs in hair. The concentrations of most PFRs in the distal segments were 1.5~8.6 times higher than those in the proximal segments of the hair (t-test, p<0.05), which may be due to the longer exposure time of the distal segments to external sources. The values of log (PFR concentrations-distal/PFR concentrations-proximal) were positively and significantly correlated with log KOA of PFRs (p<0.05, r=0.68), indicating that PFRs with a higher log KOA tend to accumulate in hair at a higher rate than PFRs with a lower log KOA. Using combined segments of female hair, significantly higher PFR concentrations were observed in female hair than in male hair. In contrast, female hair exhibited significantly lower PFR concentrations than male hair when using the same hair position for both genders (0-5cm from the scalp). The controversial results regarding gender differences in PFRs in hair highlight the importance of segmental analysis when using hair as an indicator of human exposure to PFRs.
authors.affiliation: State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Qiao
authors.affiliation: College of Resources and Environment, South China Agricultural University, Guangzhou 510642, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Xiao-Bo
authors.initials: XB
authors.lastname: Zheng
authors.affiliation: Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China. Electronic address: zhengjing@scies.org.
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Wei-Xiang
authors.initials: WX
authors.lastname: Lei
authors.affiliation: Department of Neonatology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Hong-Fang
authors.initials: HF
authors.lastname: Li
authors.affiliation: Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Mei-Huan
authors.initials: MH
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Chun-Tao
authors.initials: CT
authors.lastname: He
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: She-Jun
authors.initials: SJ
authors.lastname: Chen
authors.affiliation: State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jian-Gang
authors.initials: JG
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Luo
authors.affiliation: Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Yun-Jiang
authors.initials: YJ
authors.lastname: Yu
authors.affiliation: State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China. Electronic address: adsyzy@mail.sysu.edu.cn.
authors.forename: Zhong-Yi
authors.initials: ZY
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Bi-Xian
authors.initials: BX
authors.lastname: Mai
mesh_terms: D000328:Adult; D002681:China; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis*; D005260:Female; D005411:Flame Retardants / Q000032:analysis*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D010755:Organophosphates / Q000032:analysis*; D012737:Sex Factors; D055815:Young Adult
chemical_list: D004785:Environmental Pollutants; D005411:Flame Retardants; D010755:Organophosphates
keywords: Gender difference; Human hair; Organophosphate flame retardants; Segmental difference; Serum