Person: Conrad, André
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Conrad
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André
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Veröffentlichung 2-Mercaptobenzothiazole in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)(2020) Conrad, André; Kolossa-Gehring, Marike; Murawski, Aline; Rucic, Enrico; Schmied-Tobies, Maria Irene Hilde; Schwedler, Gerda2-Mercaptobenzothiazole (2-MBT) is widely used as a vulcanisation accelerator and is contained in many products made from natural rubber, e.g. car tires. Additionally, it is used as a fungicide in paint or fibre. Systemically human exposure to 2-MBT can occur via dermal and oral uptake or inhalation. Locally, 2-MBT can cause skin sensitisation. The International Agency for Research on Cancer (IARC) classified 2-MBT as probably carcinogenic to humans. 516 urine samples of 3- to 17-year-old children and adolescents living in Germany were analysed for the concentration of 2-MBT in the population representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). 2-MBT was quantified above the limit of quantification (LOQ) of 1.0 my g/L in 50% of the 516 samples analysed. The geometric mean of urinary 2-MBT concentration was 1.018 my g/L and 0.892 my g/gcreatinine, the arithmetic mean was 1.576 my g/L (1.351 myg/gcrea). The median concentration was below the LOQ. Analyses of subgroups revealed higher 2-MBT concentrations in children aged 3-5 years compared to 14- to 17-year-old adolescents. All urinary 2-MBT concentrations were well below the health-based guidance value HBM-I for children of 4.5 my g/L. Therefore, current exposure levels are - according to current knowledge - not of concern. For the first time, reference values can be derived for 2-MBT for children and adolescents in Germany. This will facilitate to recognise changing exposure levels in this population group in Germany and identification of unusually high exposures. © 2020 The Authors.Veröffentlichung Phthalate metabolites in urine of children and adolescents in Germany. Human biomonitoring results of the German Environmental Survey GerES V, 2014-2017(2020) Conrad, André; Daniels, Anja; Kolossa-Gehring, Marike; Lange, Rosa; Rucic, Enrico; Schmied-Tobies, Maria Irene Hilde; Schulz, Christine; Schwedler, GerdaDuring the population representative German Environmental Survey of Children and Adolescents (GerES V, 2014-2017) 2256 first-morning void urine samples from 3 to 17 years old children and adolescents were analysed for 21 metabolites of 11 different phthalates (di-methyl phthalate (DMP), di-ethyl phthalate (DEP), butylbenzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), di-cyclohexyl phthalate (DCHP), di-n-pentyl phthalate (DnPeP), di-(2-ethylhexyl) phthalate (DEHP), di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP) and di-n-octyl phthalate (DnOP)). Metabolites of DMP, DEP, BBzP, DiBP, DnBP, DEHP, DiNP and DiDP were found in 97-100% of the participants, DCHP and DnPeP in 6%, and DnOP in none of the urine samples. Geometric means (GM) were highest for metabolites of DiBP (MiBP: 26.1 my g/L), DEP (MEP: 25.8 my g/L), DnBP (MnBP: 20.9 my g/L), and DEHP (cx-MEPP: 11.9 my g/L). For all phthalates but DEP, GMs were consistently higher in the 3-5 years old children than in the 14-17 years old adolescents. For DEHP, the age differences were most pronounced. All detectable phthalate biomarker concentrations were positively associated with the levels of the respective phthalate in house dust. In GerES V we found considerably lower phthalate biomarker levels than in the preceding GerES IV (2003-2006). GMs of biomarker levels in GerES V were only 18% (BBzP), 23% (MnBP), 23% (DEHP), 29% (MiBP) and 57% (DiNP) of those measured a decade earlier in GerES IV. However, some children and adolescents still exceeded health-based guidance values in the current GerES V. 0.38% of the participants had levels of DnBP, 0.08% levels of DEHP and 0.007% levels of DiNP which were higher than the respective health-based guidance values. Accordingly, for these persons an impact on health cannot be excluded with sufficient certainty. The ongoing and substantial exposure of vulnerable children and adolescents to many phthalates confirms the need of a continued monitoring of established phthalates, whether regulated or not, as well as of potential substitutes. With this biomonitoring approach we provide a picture of current individual and cumulative exposure developments and body burdens to phthalates, thus providing support for timely and effective chemicals policies and legislation. © 2020 The Authors. Published by Elsevier GmbH.Veröffentlichung Polycyclic aromatic hydrocarbons (PAH) in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)(2020) Conrad, André; Kolossa-Gehring, Marike; Murawski, Aline; Roth, Alexandra; Rucic, Enrico; Schmied-Tobies, Maria Irene Hilde; Schwedler, GerdaPolycyclic aromatic hydrocarbons (PAH) mainly originate from incomplete combustion of organic materials and are, among other sources, found in traffic emissions, smoked or barbecued food, leafy vegetables, and tobacco smoke. Some PAH or their metabolites are hazardous for health and classified as carcinogenic, mutagenic, or toxic to reproduction. Urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for concentrations of metabolites of the PAH fluorene, naphthalene, phenanthrene, and pyrene in the population-representative German Environmental Survey for Children and Adolescents GerES V (2014-2017). PAH metabolites were analysed in urine samples of 516 participants and could be quantified in 88ââą Ì100% of the samples. Geometric mean concentrations were: 0.785 my g/L (0.688 my g/gcreatinine) for 1-OH-naphthalene, 4.233 my g/L (3.706 my g/gcrea) for 2-OH-naphthalene, 0.139 my g/L (0.122 my g/gcrea) for 1-OH-phenanthrene, 0.085 my g/L (0.075 my g/gcrea) for 2-OH-phenanthrene, 0.131 my g/L (0.115 my g/gcrea) for 3-OH-phenanthrene, 0.045 my g/L (0.040 my g/gcrea) for 4-OH-phenanthrene, 0.058 my g/L (0.050 my g/gcrea) for 9-OH-phenanthrene, 0.511 my g/L (0.448 my g/gcrea) for Σ-OH-phenanthrene, and 0.099 my/L (0.087 my g/gcrea) for 1-OH-pyrene. Analyses of subgroups revealed higher PAH metabolite concentrations in young children compared to adolescents, and also in residents of former East Germany compared to those living in former West Germany. Increased urinary PAH metabolite concentrations were found in participants using domestic fuel for heating or gas for cooking. Plastic objects were identified as another potential source of exposure. Urinary concentrations of naphthalene and fluorene metabolites were elevated in active smokers and to the same extent in non-smokers exposed to passive smoking. Comparison with previous cycles of GerES revealed a decrease over time and a further decline in the still significant differences in urinary PAH metabolite concentrations of participants living in former East versus West Germany. © 2020 Published by Elsevier GmbH.Veröffentlichung Per- and polyfluoroalkyl substances in blood plasma - Results of the German Environmental Survey for children and adolescents 2014-2017 (GerES V)(2020) Conrad, André; Duffek, Anja; Kolossa-Gehring, Marike; Lange, Rosa; Rucic, Enrico; Schulte, Christoph; Wellmitz, JörgThe 5th cycle of the German Environmental Survey (GerES V) investigated the internal human exposure of children and adolescents aged 3-17 years in Germany to per- and polyfluoroalkyl substances (PFAS). The fieldwork of the population-representative GerES V was performed from 2014 to 2017. In total, 1109 blood plasma samples were analysed for 12 PFAS including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS). PFOS was quantified in all and PFOA in almost all samples, demonstrating ubiquitous exposure. The highest geometric mean concentrations measured were 2.49 ng/mL for PFOS, followed by PFOA (1.12 ng/mL) and PFHxS (0.36 ng/mL), while concentrations of other PFAS were found in much lower concentrations. The 95th percentile levels of PFOS and PFOA were 6.00 and 3.24 ng/mL, respectively. The results document a still considerable exposure of the young generation to the phased out chemicals PFOS and PFOA. The observed exposure levels vary substantially between individuals and might be due to different multiple sources. The relative contribution of various exposure parameters such as diet or the specific use of consumer products need to be further explored. Although additional investigations on the time trend of human exposure are warranted, GerES V underlines the need for an effective and sustainable regulation of PFAS as a whole. Source: © 2020 Elsevier GmbHVeröffentlichung Indoor VOCs, aldehydes and particle measurements in the German Environmental Survey for Children and Adolescents (GerES), 2014-2017(2019) Bethke, Robert; Birmili, Wolfram; Brenske, Klaus-Reinhard; Conrad, André; Daniels, Anja; Kolossa-Gehring, Marike; Kura, Jürgen; Miethig, Stefan; Neumann, Konrad; Niemeyer, Thomas; Pietsch, Axel; Rucic, Enrico; Schechner, NadineVeröffentlichung Hexamoll® DINCH and DPHP metabolites in urine of children and adolescents in Germany. Human biomonitoring results of the German Environmental Survey GerES V, 2014-2017(2019) Conrad, André; Kolossa-Gehring, Marike; Rucic, Enrico; Schmied-Tobies, Maria Irene Hilde; Schulz, Christine; Schwedler, GerdaThe production and use of the plasticisers Hexamoll® DINCH (di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate) and DPHP (di-(2-propylheptyl) phthalate) have increased after both chemicals were introduced into the market in the early 2000s as substitutes for restricted high molecular weight phthalates. During the population representative German Environmental Survey (GerES) of Children and Adolescents (GerES V, 2014-2017), we collected urine samples and measured the concentrations of DINCH and DPHP metabolites in 2228 and in a subsample of 516 participants, respectively. We detected DINCH and DPHP metabolites in 100% and 62% of the 3-17 years old children and adolescents, respectively. Geometric means of DINCH metabolites were 2.27 myg/L for OH-MINCH, 0.93 myg/L for oxo-MINCH, 1.14 myg/L for cx-MINCH and 3.47 myg/L for DINCH (Sigma of OH-MINCH + cx-MINCH). Geometric means of DPHP metabolites were 0.30 myg/L for OH-MPHP, 0.32 myg/L for oxo-MPHP and 0.64 myg/L for DPHP (Sigma of OH-MPHP + oxo-MPHP). The 3-5 years old children had almost 3-fold higher DINCH biomarkers levels than adolescents (14-17 years). Higher concentrations of DPHP biomarkers among young children only became apparent after creatinine adjustment. Urinary levels of DINCH but not of DPHP biomarkers were associated with the levels of the respective plasticisers in house dust. When compared to HBM health-based guidance values, we observed no exceedance of the HBM-I value of 1 mg/L for DPHP (Sigma of OH-MPHP + oxo-MPHP). However, 0.04% of the children exceeded the health based guidance value HBM-I of 3 mg/L for DINCH (Sigma of OH-MINCH + cx-MINCH). This finding shows that even a less toxic replacement of restricted chemicals can reach exposures in some individuals, at which, according to current knowledge, health impacts cannot be excluded with sufficient certainty. In conclusion, we provide representative data on DINCH and DPHP exposure of children and adolescents in Germany. Further surveillance is warranted to assess the substitution process of plasticisers, and to advise exposure reduction measures, especially for highly exposed children and adolescents. Providing the results to the European HBM Initiative HBM4EU will support risk assessment and risk management not only in Germany but also in Europe. © 2019 The Authors. Published by Elsevier GmbHVeröffentlichung Human biomonitoring reference values: Differences and similarities between approaches for identifying unusually high exposure of pollutants in humans(2019) Apel, Petra; Conrad, André; Kolossa-Gehring, Marike; Rucic, Enrico; Vogel, NinaIn exposure and risk assessment, the indication of unusually high exposure levels in humans to chemicals has been considered as an important objective for decades. To realize this objective, reference values (RV) need to be derived. However, while there is a tendency towards using the 95th percentile as a basis for deriving these reference values there is still no consensus. Moreover, side approaches have evolved including deriving RVs based on other percentiles, reporting multiple RVs or only reporting percentiles. The purpose of this article is to give an overview of the current literature, to point out differences and similarities between existing approaches, and to highlight important criteria for the derivation of RVs. We observe the majority of studies to base RVs on the 95th percentile and its 95% confidence interval which can been justified by statistical paradigms, present arguments for a single defined reference value, and discuss characteristics which call for more consistency. To conclude, our overview provides a first step towards a more homogenous and standardized derivation procedure to identify unusually high exposures in exposure science. © 2018 The Authors. Published by Elsevier GmbH.Veröffentlichung Metabolites of the substitute plasticiser Di-(2-ethylhexyl) terephthalate (DEHTP) in urine of children and adolescents investigated in the German Environmental Survey GerES V, 2014-2017(2020) Conrad, André; Koch, Holger Martin; Kolossa-Gehring, Marike; Rucic, Enrico; Schmied-Tobies, Maria Irene Hilde; Schwedler, GerdaMetabolites of di-(2-ethylhexyl) terephthalate (DEHTP), a substitute for ortho-based phthalate plasticisers like di-(2-ethylhexyl) phthalate (DEHP), were analysed in 2112 first-morning void urine samples from children and adolescents aged 3-17 years, participating in the population representative German Environmental Survey on Children and Adolescents, GerES V 2014-2017. The major metabolite 5cx-MEPTP was detected in all urine samples with a geometric mean (GM) of 7.39 (my)g/L, with highest levels in the mg/L range. The GM for the other metabolites were 0.55 (my)g/L for 5OH-MEHTP, 0.54 (my)g/L for 5oxo-MEHTP and below the limit of quantification (LOQ) for 2cx-MMHTP. As already observed for other plasticisers and their substitutes, the youngest children (3-5 years) had 2-2.5-fold higher urinary DEHTP metabolite levels compared to 14-17 years old adolescents. High urinary levels of DEHTP metabolites were associated with high DEHTP concentrations in house dust. None of the samples analysed exceeded the toxicologically derived German human biomonitoring guidance value (HBM-I-Value) of 1.8 mg/L for 5cx-MEPTP. Comparison with DEHTP levels reported in other HBM studies worldwide confirmed a widespread exposure of children, adolescents and adults, with considerably higher exposures (2.6-7 fold) reported in the United States. In GerES V, exposure data for 12 different phthalates and the phthalate substitute DINCH were generated as well. Together with the data for DEHTP presented in this manuscript, GerES V allows a current and comprehensive overview on the concurrent exposure of German children and adolescents to common plasticisers. Further evaluation of aggregate exposure characteristics shall support efforts to reduce chemical hazard burden from plasticisers in Germany and beyond. © 2020 The Author(s).Veröffentlichung The methylisothiazolinone and methylchloroisothiazolinone metabolite N-methylmalonamic acid (NMMA) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)(2020) Conrad, André; Kolossa-Gehring, Marike; Murawski, Aline; Rucic, Enrico; Schmied-Tobies, Maria Irene HildeMixtures of methylisothiazolinone and methylchloroisothiazolinone are used as biocides in cosmetics, cleaning agents, and water-based paint. A biomonitoring method to evaluate exposure to these compounds was developed using N-methylmalonamic acid (NMMA), the main metabolite of both, methylisothiazolinone and methylchloroisothiazolinone, as the exposure biomarker. First-morning void urine samples (N = 2078) of 3- to 17-year-old children and adolescents living in Germany were analysed for concentrations of NMMA in the population representative German Environmental Survey for Children and Adolescents GerES V (2014-2017). NMMA was quantified in almost all samples, with a geometric mean concentration of 6.245 My g/L (5.303 my g/gcrea) and a 95th percentile of 15.0 my g/L (12.6 ÎÌg/gcrea). Urinary concentrations could not be related to self-reported application of specific cleaning agents or personal care products, leaving potential, specific sources of exposure unrevealed as most products relevant for isothiazolinone exposure are used ubiquitously. For the first time, reference values can be derived for urinary NMMA for children and adolescents in Germany, facilitating a more substantiated exposure assessment. © 2020 Published by Elsevier GmbH.Veröffentlichung The German Environmental Survey for Children and Adolescents 2014-2017 (GerES V) - Study population, response rates and representativeness(2021) Conrad, André; Kolossa-Gehring, Marike; Peisker, Jasmin; Reiber, Lena; Rucic, Enrico; Schulz, ChristineThe German Environmental Survey (GerES) is a population-representative, cross-sectional study on environ-mental exposures of the general population of Germany. GerES has repeatedly been conducted since 1985 by the German Environment Agency (UBA) in close collaboration with the Health Interview and Examination Surveys of the Robert Koch Institute (RKI). In the German Environmental Survey for Children and adolescents 2014-2017 (GerES V) pollutants and other environmental stressors were measured in human samples as well as in the homes of 3- to 17-year-old children and adolescents. Interviews were conducted about health-related behaviors and living conditions. The GerES V basic program encompassed examinations of whole blood, blood plasma, morning urine and drinking water samples, measurements of ultrafine particles and noise levels, comprehensive stan-dardized interviews, and self-administrated questionnaires. Additional modules on volatile organic compounds and aldehydes, particulate matter (PM2.5) in indoor air, organic compounds in drinking water and pollutants in house dust were conducted in subsamples. Potential GerES V participants were identified and attained by the RKI from those participants who were examined and interviewed for the cross-sectional component of the second follow-up to the German Health Interview and Examination Survey for Children and Adolescents (KiGGS Wave 2). The gross sample of GerES V comprised 3031 children and adolescents of which 2294 finally took part in the survey. This equals a total response rate of 75.7 %. Response rates varied, depending on region, type of mu-nicipality, age and sex, from 66.0 % to 78.3 %. By calculating individual case weights, discrepancies due to sample design and non-response between the GerES V sample and the whole population could be considered in statistical analysis. Therefore, the representativeness of the GerES V results with regard to age, sex, community size and region was assured. © 2021 Elsevier GmbH.