Determinants of bisphenol A and phthalate metabolites in urine of Flemish adolescents Tinne Geens a , Liesbeth Bruckers b , Adrian Covaci a,n , Greet Schoeters c,d , Tine Fierens c,e , Isabelle Sioen e , Guido Vanermen f , Willy Baeyens g , Bert Morrens h , Ilse Loots h , Vera Nelen i , Benoit Nemery de Bellevaux j , Nik Van Larebeke k , Elly Den Hond c a Toxicological Center, University of Antwerp, Belgium b Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Belgium c Environmental Risk and Health Unit, Flemish Institute for Technological Research (VITO), Belgium d Department of Biomedical Sciences, University of Antwerp, Belgium e Department of Public Health, Ghent University, Belgium f Environmental Analysis and Technology Unit, Flemish Institute for Technological Research (VITO), Belgium g Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel (VUB), Belgium h Department of Sociology, University of Antwerp, Belgium i Provincial Institute for Hygiene, Antwerp, Belgium j Department of Public Health, Occupational and Environmental Medicine, University of Leuven, Belgium k Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel (VUB), Belgium and (retired) Study Centre for Carcinogenesis and Primary Prevention of Cancer, Ghent University, Belgium article info Article history: Received 3 February 2014 Received in revised form 23 July 2014 Accepted 25 July 2014 Keywords: Bisphenol-A Phthalate metabolites Biomonitoring Determinants of exposure Adolescents Flanders abstract As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and different phthalate metabolites were analyzed, for the first time, in the urine of 210 adolescents in Flanders, Belgium. All chemicals had a detection frequency above 90%. For all compounds, except the sum of DEHP, highest levels were detected during spring. Average values for the Flemish adolescents were in an agreement with concentrations found in different international studies, all confirming the ubiquity of BPA and phthalate exposure. There was a significant correlation between BPA and the different phthalate metabolites (r between 0.26 and 0.39; p o0.01). Shared sources of exposure to BPA and phthalates, such as food packaging, were suggested to be responsible for this positive correlation. Different determinants of exposure were evaluated in relation to the urinary concentrations of these chemicals. For BPA, a significant association was observed with household income class, smoking and exposure to environmental tobacco smoke. For phthalates, the following significant associations were observed: age (MBzP), educational level of the adolescent (MBzP), equivalent household income (MnBP), use of personal care products (MnBP and MBzP), wall paper in house (MnBP and MBzP) and use of local vegetables (MnBP and MBzP). & 2014 Elsevier Inc. All rights reserved. 1. Introduction Bisphenol A (BPA) is a high-volume chemical which is mainly used as monomer in the production of polycarbonate and epoxy resins. Polycarbonate can be used for construction materials, optical media and packaging materials. Epoxy resins are used as adhesives and coatings, e.g. internal coating of food and beverage cans. Other potential sources for exposure to BPA are thermal paper, dental sealants, dust, medical devices, etc. (Geens et al., 2011, 2012; von Goetz et al., 2010) After oral ingestion, BPA is rapidly metabolized and converted in the gut wall and liver into BPA-glucuronide and BPA-sulfate. This is considered a detoxification reaction, since these conjugates do not show estrogenic activity. Within a few hours, BPA- glucuronide and BPA-sulfate are excreted in the urine. Therefore, concentrations of BPA in serum are low, and consequently, urine is a more appropriate matrix for biomonitoring of BPA. Since BPA is almost completely excreted in urine within 24 h after exposure, urinary concentrations can be used for back calculation to estimate Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/envres Environmental Research http://dx.doi.org/10.1016/j.envres.2014.07.020 0013-9351/& 2014 Elsevier Inc. All rights reserved. n Correspondence to: Toxicological Center, University of Antwerp, Universiteits- plein 1, 2610 Wilrijk (Antwerp), Belgium. Tel.: þ32 3 265 2498. E-mail address: adrian.covaci@uantwerpen.be (A. Covaci). Environmental Research 134 (2014) 110–117