Three cycles of human biomonitoring in Flanders - Time trends observed in the Flemish Environment and Health Study.
To follow time trends in exposure to environmental chemicals, three successive campaigns of the Flemish Environment and Health Study (FLEHS) have recruited and sampled in total 5825 participants between 2002 and 2014. Cord samples from newborns, urine and blood samples from 14 to 15 years old adolescents and from adults between 50 and 65 years old were analysed in geographical representative samples of the Flemish population. The data of the different campaigns were considered per age group and per biomarker after adjustment for predefined covariates to take into account differences in characteristics of the study populations over time. Geometric means were calculated. Multiple linear regression was used to evaluate time trends. The concentration of serum biomarkers for persistent organic pollutants (POPs), such as marker polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p'-DDE), the major metabolite of dichlorodiphenyltrichloroethane (DDT), and hexachlorobenzene (HCB) expressed per g lipid, decreased significantly with time. The levels of DDE in all age groups and those of PCBs in cord and adolescent serum samples were almost halved in a time period of ten years. HCB levels were reduced by a factor of 4 in adolescents and in adults. Mean serum concentrations of the more recently regulated perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were significantly lower in cord samples of 2013 compared to samples of 2007. The decline was more pronounced for PFOS than for PFOA. In the same period, mean metabolite levels of di-2-ethylhexyl phthalate (DEHP) and of di-n-butyl phthalate (DBP) decreased significantly in urine samples of adolescents with sharper declines for DEHP than for DBP. Cadmium and lead levels in cord and adolescent blood samples were significantly lower in the recent campaigns than 10 years before. Also the mean urinary cadmium level in adults was 35% lower compared to adult samples of 2002. Such favourable trends were not observed for arsenic and thallium measured in cord blood. Similar, the concentrations of 1-hydroxypyrene, a marker for exposure to polycyclic aromatic hydrocarbons (PAHs), was not lower in urine from adolescents sampled in 2013 compared to 2003. In contrast, concentrations of t,t'-muconic acid, a marker of benzene exposure, showed clearly reduced levels. The FLEHS program shows that concentrations of well-regulated chemicals especially traditional POPs and cadmium and lead are decreasing in the population of Flanders. Response to regulatory measures seems to happen rapid, since concentrations in humans of specific regulated perfluorinated compounds and phthalates were significantly reduced in five years time. Biomarker concentrations for arsenic, thallium, and polyaromatic hydrocarbons are not decreasing in this time span and further follow up is warranted.
Flemish Institute for Technological Research (VITO), Mol, Belgium; Dept of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Dept of Environmental Medicine, University of Southern Denmark, Odense, Denmark. Electronic address: greet.schoeters@vito.be.
Greet
G
Schoeters
Flemish Institute for Technological Research (VITO), Mol, Belgium.
Eva
E
Govarts
Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Diepenbeek, Belgium.
Liesbeth
L
Bruckers
Flemish Institute for Technological Research (VITO), Mol, Belgium; Provinciaal Instituut voor Hygiëne (PIH), Antwerp, Belgium.
Elly
E
Den Hond
Provinciaal Instituut voor Hygiëne (PIH), Antwerp, Belgium.
Vera
V
Nelen
Department of Public Health, Ghent University, Ghent, Belgium.
Stefaan
S
De Henauw
Department of Public Health, Ghent University, Ghent, Belgium.
Isabelle
I
Sioen
Centre of Environmental Sciences, Hasselt University, Belgium; Department of Public Health and Primary Care, KULeuven, Leuven, Belgium.
Tim S
TS
Nawrot
Centre of Environmental Sciences, Hasselt University, Belgium.
Michelle
M
Plusquin
Centre of Environmental Sciences, Hasselt University, Belgium.
Annette
A
Vriens
Toxicological Centre, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium.
Adrian
A
Covaci
Faculty of Social Sciences, University of Antwerp, Antwerp, Belgium.
Ilse
I
Loots
Faculty of Social Sciences, University of Antwerp, Antwerp, Belgium.
Bert
B
Morrens
Faculty of Social Sciences, University of Antwerp, Antwerp, Belgium.
Dries
D
Coertjens
Department of Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussel (VUB), Elsene, Belgium.
Nicolas
N
Van Larebeke
Department of Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussel (VUB), Elsene, Belgium.
Sam
S
De Craemer
Department of Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussel (VUB), Elsene, Belgium.
Kim
K
Croes
Flemish Institute for Technological Research (VITO), Mol, Belgium.
Nathalie
N
Lambrechts
Flemish Institute for Technological Research (VITO), Mol, Belgium.
Ann
A
Colles
Department of Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussel (VUB), Elsene, Belgium.
Willy
W
Baeyens
D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking / Q000097:blood; D001151:Arsenic / Q000097:blood; D001530:Belgium; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D005466:Fluorocarbons / Q000097:blood; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood; D007231:Infant, Newborn; D007854:Lead / Q000097:blood; D008297:Male; D008875:Middle Aged; D011721:Pyrenes / Q000652:urine; D012907:Smoking / Q000097:blood; D013793:Thallium / Q000097:blood; D055815:Young Adult
D004785:Environmental Pollutants; D005466:Fluorocarbons; D006843:Hydrocarbons, Chlorinated; D011721:Pyrenes; D007854:Lead; D013793:Thallium; C033146:1-hydroxypyrene; D001151:Arsenic
Benzene; Human biomonitoring; Metals; Persistent organochlorine compounds; Phthalates; Polyaromatic hydrocarbons; Time trends