title: Monthly variation in faeces:blood concentration ratio of persistent organic pollutants over the first year of life: a case study of one infant.
abstract: Previous studies have found that the concentrations of a range of persistent organic pollutants (POPs) in faeces is linearly proportional to the POP concentrations in blood of human adults irrespective of age and gender. In order to investigate the correlation between POP concentrations in faeces and blood in infants, the monthly variation of POP concentrations in faeces over the first year of life of one infant was investigated in this study and compared to modelled blood concentrations. Faecal samples were collected from one male infant daily. The samples were pooled by month and analysed for three selected POPs (2,2('),4,4('),5,5(')-Hexachlorobiphenyl (PCB153), p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and 2,2('),4,4'-tetrabromodiphenyl ether (BDE47)). The POP concentrations in faecal samples increased for the first four months by a factor of 2.9, 4.9 and 1.4 for PCB153, BDE47, and p,p'-DDE, respectively. The faecal concentrations of all POPs decreased rapidly following the introduction of formula and solid food to the diet and subsequent weaning of the infant. Further, a one-compartment model was developed to estimate the daily POP concentrations in the blood of the infant. The POP concentrations in blood were predicted to vary much less over the first year than those observed in faeces. The faeces:blood concentration ratio of selected POPs (Kfb) differed significantly (P<0.0001) between the period before and after weaning, and observed changes in Kfb are far greater than the uncertainty in the estimated Kfb. A more stable Kfb after weaning indicates the possibility of applying the stable Kfb values for non-invasive assessment of internal exposure in infants after weaning. The intra-individual variation in Kfb in infants is worthy of further investigation.
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia. Electronic address: y.chen16@uq.edu.au.
authors.forename: Yiqin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, Sweden.
authors.forename: Michael S
authors.initials: MS
authors.lastname: McLachlan
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Sarit
authors.initials: S
authors.lastname: Kaserzon
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Xianyu
authors.initials: X
authors.lastname: Wang
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Weijs
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Gallen
authors.affiliation: School of Public Health and Social Work and Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Australia.
authors.forename: Leisa-Maree L
authors.initials: LM
authors.lastname: Toms
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia; Summit Toxicology, LLP, Falls Church, VA, USA.
authors.forename: Lesa L
authors.initials: LL
authors.lastname: Aylward
authors.affiliation: Children's Health and Environment Program, Queensland Children's Medical Research Institute, Brisbane, Australia; Child Health Research Centre, The University of Queensland, Australia.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Sly
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Australia.
authors.forename: Jochen F
authors.initials: JF
authors.lastname: Mueller
mesh_terms: D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis / Q000097:blood*; D004785:Environmental Pollutants / Q000032:analysis / Q000097:blood*; D005243:Feces / Q000737:chemistry*; D055768:Halogenated Diphenyl Ethers / Q000032:analysis / Q000097:blood*; D006801:Humans; D007223:Infant; D007700:Kinetics; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D008962:Models, Theoretical; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000097:blood*; D011237:Predictive Value of Tests
chemical_list: D004785:Environmental Pollutants; D055768:Halogenated Diphenyl Ethers; C511295:2,2',4,4'-tetrabromodiphenyl ether; D003633:Dichlorodiphenyl Dichloroethylene; D011078:Polychlorinated Biphenyls; C014024:2,4,5,2',4',5'-hexachlorobiphenyl
keywords: Faeces:blood concentration ratio; Infant; Model; Noninvasive bio-monitoring; POPs