title: Monitoring chlorinated persistent organic pollutants in adolescents in Flanders (Belgium): concentrations, trends and dose-effect relationships (FLEHS II).
abstract: BACKGROUND
  In 2007, the second cycle of the Flemish human biomonitoring survey started, with a main focus on 14-15 year-old adolescents.
  
  
  OBJECTIVE
  The main objectives were generating reference values for exposure markers, determining the pollution pressure in industrial hotspots and establishing dose-effect relationships between exposure to pollutants and hormone levels, sexual development, asthma and allergy, genotoxic and hematological markers.
  
  
  METHODS
  Geometric means with 95% confidence intervals (CI) were calculated for a reference population of 200 14-15 year-old adolescents. Stepwise multiple regression analyses with correction for confounders and covariates were performed to establish dose-effect relationships.
  
  
  RESULTS
  Geometric mean concentrations (with 95% CI) of 49.6 (45.7, 53.8), 70.8 (63.6, 78.8) and 8.34 (7.76, 8.97) n gg(-1) lipid for the sum of PCB 138, 153 and 180, p,p'-DDE and HCB were respectively 23%, 26% and 60% lower than those obtained five years earlier. Geometric mean concentrations of 108 (101, 114) and 32.1 (30.1, 34.2) pgCALUX-BEQg(-1) lipid were observed for the PCDD/Fs and dioxin-like PCBs, respectively. Multiple dose-effect relationships were observed between POPs and several effect markers, including positive (boys) and negative (girls) associations with data on sexual development and positive associations with asthma, animal allergy and free thyroxine (boys and girls).
  
  
  CONCLUSIONS
  Our findings suggest that chlorinated POP concentrations are decreasing over time and that even relatively low concentrations are associated with biological effects.
authors.affiliation: Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium. Electronic address: kim.croes@vub.ac.be.
authors.forename: Kim
authors.initials: K
authors.lastname: Croes
authors.affiliation: Environmental Health and Risk, VITO, Mol, Belgium.
authors.forename: Elly
authors.initials: E
authors.lastname: Den Hond
authors.affiliation: Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Bruckers
authors.affiliation: Political and Social Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Ilse
authors.initials: I
authors.lastname: Loots
authors.affiliation: Political and Social Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Bert
authors.initials: B
authors.lastname: Morrens
authors.affiliation: Provincial Institute for Hygiene, Antwerp, Belgium.
authors.forename: Vera
authors.initials: V
authors.lastname: Nelen
authors.affiliation: Environmental Health and Risk, VITO, Mol, Belgium.
authors.forename: Ann
authors.initials: A
authors.lastname: Colles
authors.affiliation: Environmental Health and Risk, VITO, Mol, Belgium.
authors.forename: Greet
authors.initials: G
authors.lastname: Schoeters
authors.affiliation: Department of Public Health, Ghent University, Ghent, Belgium.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sioen
authors.affiliation: Toxicological Centre, University of Antwerp, Antwerp, Belgium.
authors.forename: Adrian
authors.initials: A
authors.lastname: Covaci
authors.affiliation: Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Tara
authors.initials: T
authors.lastname: Vandermarken
authors.affiliation: Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Van Larebeke
authors.affiliation: Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Willy
authors.initials: W
authors.lastname: Baeyens
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001249:Asthma / Q000139:chemically induced; D001530:Belgium; D015415:Biomarkers / Q000097:blood / Q000378:metabolism*; D015992:Body Mass Index; D004147:Dioxins / Q000032:analysis* / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000032:analysis* / Q000633:toxicity; D005260:Female; D042341:Gonadal Hormones / Q000097:blood; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology; D007118:Immunoassay; D008297:Male; D016017:Odds Ratio; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000633:toxicity; D012016:Reference Values; D012044:Regression Analysis; D046468:Sexual Development / Q000187:drug effects; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D015415:Biomarkers; D004147:Dioxins; D004785:Environmental Pollutants; D042341:Gonadal Hormones; D013963:Thyroid Hormones; D011078:Polychlorinated Biphenyls
keywords: Chlorinated POPs; Dose–effect; FLEHS II; Hormones; Human biomonitoring; Sexual development