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Weber, Till

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  • Veröffentlichung
    Long-term monitoring of mercury in young German adults: Time trend analyses from the German Environmental Specimen Bank, 1995-2018
    (2022) Bartel-Steinbach, Martina; Lermen, Dominik; Conrad, André; Gwinner, Frederik; Kolossa-Gehring, Marike; Weber, Till
    As highlighted in the Minamata Convention, Mercury (Hg) in its various forms poses a substantial risk to human health and the environment. The health relevance of Hg is also recognized by the European Human Biomonitoring Initiative (HBM4EU), which classifies Hg as a priority substance, since considerable knowledge and data gaps on Hg exposure levels and their changes over time still exist in Europe. The German Environmental Specimen Bank (German ESB) provides valuable policy relevant data and long-term trends of substance exposure on a national level for international comparison and evaluation. In this study we analysed data of the German ESB on Hg exposure of young adults aged 20 to 29 including data on urinary Hg levels from 1995 to 2018 and whole blood Hg levels from 2001 to 2010. Results show a clear decrease in both, about 86% in urine total daily Hg excretion from 1995 (0.76 (micro)g/L) to 2018 (0.11 (micro)g/L) (n = 10,069) and about 57% in blood concentrations of Hg from 2001 (1.76 (micro)g/L) to 2010 (0.77 (micro)g/L) (n = 4085). Over the investigated timeframe only a few values exceeded the toxicologically derived health based guidance value HBM I for blood and urine, with these exceedances decreasing over time in line with the general trend. The factors mostly influencing Hg excretion identified in this study are dental amalgam as well as fish and seafood consumption. Besides other factors (e.g. age and sex), also airborne Hg exposure appears to be a low but evident influencing factor in Germany. Although a considerable decrease in internal Hg exposure is recognized in the last decades, the current low-level exposure may cause adverse health effects especially to vulnerable groups such as pregnant women and children. To further elucidate and evaluate current exposure sources and to reduce human exposure to Hg, continuous environmental and human biomonitoring is needed. © 2022 The Authors.
  • Veröffentlichung
    Improving the risk assessment of pesticides through the integration of Human Biomonitoring and Food Monitoring Data: a case study for chlorpyrifos
    (2022) Tarazona, Jose V.; González-Caballero, Maria Carmen; Alba-Gonzalez, Mercedes de; Kolossa-Gehring, Marike; Weber, Till
    The risk assessment of pesticide residues in food is a key priority in the area of food safety. Most jurisdictions have implemented pre-marketing authorization processes, which are supported by prospective risk assessments. These prospective assessments estimate the expected residue levels in food combining results from residue trials, resembling the pesticide use patterns, with food consumption patterns, according to internationally agreed procedures. In addition, jurisdictions such as the European Union (EU) have implemented large monitoring programs, measuring actual pesticide residue levels in food, and are supporting large-scale human biomonitoring programs for confirming the actual exposure levels and potential risk for consumers. The organophosphate insecticide chlorpyrifos offers an interesting case study, as in the last decade, its acceptable daily intake (ADI) has been reduced several times following risk assessments by the European Food Safety Authority (EFSA). This process has been linked to significant reductions in the use authorized in the EU, reducing consumers exposure progressively, until the final ban in 2020, accompanied by setting all EU maximum residue levels (MRL) in food at the default value of 0.01 mg/kg. We present a comparison of estimates of the consumerââą Ìs internal exposure to chlorpyrifos based on the urinary marker 3,5,6-trichloro-2-pyridinol (TCPy), using two sources of monitoring data: monitoring of the food chain from the EU program and biomonitoring of European citizens from the HB4EU project, supported by a literature search. Both methods confirmed a drastic reduction in exposure levels from 2016 onwards. The margin of exposure approach is then used for conducting retrospective risk assessments at different time points, considering the evolution of our understanding of chlorpyrifos toxicity, as well as of exposure levels in EU consumers following the regulatory decisions. Concerns are presented using a color code, and have been identified for almost all studies, particularly for the highest exposed group, but at different levels, reaching the maximum level, red code, for children in Cyprus and Israel. The assessment uncertainties are highlighted and integrated in the identification of levels of concern. © 2022 by the authors.
  • Veröffentlichung
    Cadmium exposure in adults across Europe: Results from the HBM4EU Aligned Studies survey 2014-2020
    (2022) Tratnik, Janja Snoj; Kocman, David; Horvat, Milena; Kolossa-Gehring, Marike; Weber, Till
    The objectives of the study were to estimate the current exposure to cadmium (Cd) in Europe, potential differences between the countries and geographic regions, determinants of exposure and to derive European exposure levels. The basis for this work was provided by the European Human Biomonitoring Initiative (HBM4EU) which established a framework for alignment of national or regional HBM studies. For the purpose of Cd exposure assessment, studies from 9 European countries (Iceland, Denmark, Poland, Czech Republic, Croatia, Portugal, Germany, France, Luxembourg) were included and urine of 20-39 years old adults sampled in the years 2014-2021 (n = 2510). The measurements in urine were quality assured by the HBM4EU quality assurance/quality control scheme, study participants' questionnaire data were post-harmonized. Spatially resolved external data, namely Cd concentrations in soil, agricultural areas, phosphate fertilizer application, traffic density and point source Cd release were collected for the respective statistical territorial unit (NUTS). There were no distinct geographic patterns observed in Cd levels in urine, although the data revealed some differences between the specific study sites. The levels of exposure were otherwise similar between two time periods within the last decade (DEMOCOPHES - 2011-2012 vs. HBM4EU Aligned Studies, 2014-2020). The age-dependent alert values for Cd in urine were exceeded by 16% of the study participants. Exceedances in the different studies and locations ranged from 1.4% up to 42%. The studies with largest extent of exceedance were from France and Poland. Association analysis with individual food consumption data available from participants' questionnaires showed an important contribution of vegetarian diet to the overall exposure, with 35% higher levels in vegetarians as opposed to non-vegetarians. For comparison, increase in Cd levels due to smoking was 25%. Using NUTS2-level external data, positive associations between HBM data and percentage of cropland and consumption of Cd-containing mineral phosphate fertilizer were revealed, which indicates a significant contribution of mineral phosphate fertilizers to human Cd exposure through diet. In addition to diet, traffic and point source release were identified as significant sources of exposure in the study population. The findings of the study support the recommendation by EFSA to reduce Cd exposure as also the estimated mean dietary exposure of adults in the EU is close or slightly exceeding the tolerable weekly intake. It also indicates that regulations are not protecting the population sufficiently. © 2022 The Authors
  • Veröffentlichung
    Assessment of the long-term exposure to lead in four european countries using PBPK modeling
    (2023) Sy, Moustapha; Eleftheriadou, Dimitra; Jung, Christian; Kolossa-Gehring, Marike; Weber, Till
    Lead (Pb) is a naturally occurring heavy metal that received, in the last decades, much attention in the human health risk assessment community. In the European Human Biomonitoring Initiative (HBM4EU), Pb was identified as a priority substance as various scientific and policy questions were open and still to be answered. They included the further investigation of the internal exposure to Pb, the factors determining it, and its variations within European populations. The aim of this work was to develop an integrative modeling framework for the assessment of the aggregated long-term exposure to Pb in Belgium, Czech Republic, Germany, and Norway. This framework enabled predicting the concentrations of Pb in human blood (PbB) from estimates of the external exposure. The effect of past and current exposure events was accounted for, as multiple country-specific Pb concentration data in environmental compartments and diet, and estimates of the dietary intake of Pb covering a period from the 1970s until the present times were compiled. This modeling approach allowed, using a twodimensional Monte Carlo (MC2D) approach, running a population-based simulation and characterizing the inter-individual variability within the simulated populations and the uncertainty on the external exposure estimates. The predicted PbB levels were compared with the results drawn from HBM data. To the best of our knowledge, this holistic modeling approach combines for the first time temporal and country-specific trends in environmental lead concentrations to derive internal exposure, in order to get better insights into the relationship between environmental and human lead exposure, and to characterize individual exposure at different ages. © The Author(s)
  • Veröffentlichung
    Exposure to phthalates in European children, adolescents and adults since 2005: a harmonized approach based on existing HBM data in the HBM4EU Initiative
    (2023) Kolossa-Gehring, Marike; Lange, Rosa; Murawski, Aline; Rüther, Maria; Gerofke, Antje; Schmidt, Phillipp; Springer, Andrea; Vogel, Nina; Weber, Till
    Phthalates are mainly used as plasticizers and are associated inter alia with adverse effects on reproductive functions. While more and more national programs in Europe have started monitoring internal exposure to phthalates and its substitute 1,2-Cyclohexanedicarboxylic acid (DINCH), the comparability of results from such existing human biomonitoring (HBM) studies across Europe is challenging. They differ widely in time periods, study samples, degree of geographical coverage, design, analytical methodology, biomarker selection, and analytical quality assurance level. The HBM4EU initiative has gathered existing HBM data of 29 studies from participating countries, covering all European regions and Israel. The data were prepared and aggregated by a harmonized procedure with the aim to describe - as comparably as possible - the EU-wide general population's internal exposure to phthalates from the years 2005 to 2019. Most data were available from Northern (up to 6 studies and up to 13 time points), Western (11; 19), and Eastern Europe (9; 12), e.g., allowing for the investigation of time patterns. While the bandwidth of exposure was generally similar, we still observed regional differences for Butyl benzyl phthalate (BBzP), Di(2-ethylhexyl) phthalate (DEHP), Di-isononyl phthalate (DiNP), and Di-isobutyl phthalate (DiBP) with pronounced decreases over time in Northern and Western Europe, and to a lesser degree in Eastern Europe. Differences between age groups were visible for Di-n-butyl phthalate (DnBP), where children (3 to 5-year olds and 6 to 11-year olds) had lower urinary concentrations than adolescents (12 to 19-year-olds), who in turn had lower urinary concentrations than adults (20 to 39-year-olds). This study is a step towards making internal exposures to phthalates comparable across countries, although standardized data were not available, targeting European data sets harmonized with respect to data formatting and calculation of aggregated data (such as developed within HBM4EU), and highlights further suggestions for improved harmonization in future studies. © 2023 by the authors
  • Veröffentlichung
    Time Patterns in Internal Human Exposure Data to Bisphenols, Phthalates, DINCH, Organophosphate Flame Retardants, Cadmium and Polyaromatic Hydrocarbons in Europe
    (2023) Martin, Laura Rodriguez; Gilles, Liese; Helte, Emilie; Kolossa-Gehring, Marike; Lange, Rosa; Pack, Kim Laura; Schmidt, Phillipp; Vogel, Nina; Weber, Till
    Human biomonitoring (HBM) data in Europe are often fragmented and collected in different EU countries and sampling periods. Exposure levels for children and adult women in Europe were evaluated over time. For the period 2000-2010, literature and aggregated data were collected in a harmonized way across studies. Between 2011-2012, biobanked samples from the DEMOCOPHES project were used. For 2014-2021, HBM data were generated within the HBM4EU Aligned Studies. Time patterns on internal exposure were evaluated visually and statistically using the 50th and 90th percentiles (P50/P90) for phthalates/DINCH and organophosphorus flame retardants (OPFRs) in children (5-12 years), and cadmium, bisphenols and polycyclic aromatic hydrocarbons (PAHs) in women (24-52 years). Restricted phthalate metabolites show decreasing patterns for children. Phthalate substitute, DINCH, shows a non-significant increasing pattern. For OPFRs, no trends were statistically significant. For women, BPA shows a clear decreasing pattern, while substitutes BPF and BPS show an increasing pattern coinciding with the BPA restrictions introduced. No clear patterns are observed for PAHs or cadmium. Although the causal relations were not studied as such, exposure levels to chemicals restricted at EU level visually decreased, while the levels for some of their substitutes increased. The results support policy efficacy monitoring and the policy-supportive role played by HBM. © 2023 by the authors
  • Veröffentlichung
    Nonylphenol (NP) exposure in Germany between 1991 and 2021: urinary biomarker analyses in the German Environmental Specimen Bank (ESB)
    (2022) Ringbeck, Benedikt; Kolossa-Gehring, Marike; Bury, Daniel; Weber, Till
    Nonylphenol (NP) is a high production volume chemical with a wide range of uses, e.g. in NP ethoxylates (NPEO). NP and NPEO have become ubiquitous in the environment and are considered of concern due to their general ecotoxicity and endocrine disrupting properties. However, knowledge on human exposure is scarce. In this study, we analyzed novel NP metabolites (OH-NP and oxo-NP) as robust biomarkers of exposure in 24h-urine samples from the German Environmental Specimen Bank (ESB). This enables us to reliably determine the individual NP body burden and to retrospectively evaluate NP exposure over the past 30 years. We analyzed 660 urine samples from eleven sampling years between 1991 and 2021. All samples were from young German adults between 20 and 29 years of age. OH-NP was quantifiable in all samples until 2017. In 2019 and 2021, the frequency of samples above the LOQ dropped to 90% and 77%, respectively. Median OH-NP concentrations significantly decreased from 4.32 (micro)g/L in 1991 to 0.70 (micro)g/L in 2021. OH-NP and oxo-NP levels correlated strongly, but oxo-NP concentrations and detections were considerably lower, in line with its known lower metabolic conversion. Reverse dosimetry back-calculated daily intakes (DI) of NP, based on OH-NP, decreased by almost a factor of four from medians of 0.16 (micro)g/(kg bw*d) in 1991 to 0.04 (micro)g/(kg bw*d) in 2021, respectively. The major drop took place only after 2012. This came as a surprise, because strict restrictions had been enacted much earlier in the EU, in 2003. All NP DIs were below the provisional tolerable daily intake of 5 (micro)g/(kg bw*d) from the Danish Environmental Agency. DIs back-calculated from the ESB biomonitoring data agree well with calculations from food. This indicates to contaminated foodstuff as a major source of exposure. The time lag of regulatory restrictions to decreasing human exposure levels, the general lack of knowledge on exposure levels in susceptible populations such as children, and the ongoing worldwide use of NP underline the urgent need to continue monitoring NP exposures in Germany and worldwide. With these novel NP biomarkers, we provide a robust and sensitive tool for exposure and risk assessments, complementing environmental monitoring. © 2022 The Authors
  • Veröffentlichung
    N-methylmalonamic acid (NMMA) as metabolite of methylisothiazolinone and methylchloroisothiazolinone in 24-h urine samples of the German Environmental Specimen Bank from 2000 to 2017
    (2020) Schettgen, Thomas; Kolossa-Gehring, Marike; Rüther, Maria; Weber, Till
    Methylisothiazolinone (MI) and the mixture of methylchloroisothiazolinone/methylisothiazolinone (MCI/MI, 3:1) are widespread biocides used in cosmetics, household products, paints or as disinfectant in air-conditioning systems. Exposure to these compounds has raised concerns due to their sensitizing potential, as rates of skin sensitization were reported to increase in the last decade. We have analyzed N-methylmalonamic acid (NMMA), a common metabolite of MI and MCI in 24-h urine samples of the German Environmental Specimen Bank collected from 480 participants (240 male/240 female) between the years 2000 and 2017. Using these data, we were able to calculate the overall daily intake of MI and/or MCI/MI (3:1) of the study participants and point out time trends. NMMA was determined in all urine samples investigated above the LOQ of 0.5 (my)g/L urine. Median and 95th percentile level of NMMA in all 24-h urine samples was 4.1 (my)g/g creatinine and 8.5 (my)g/g creatinine, respectively. This would correspond to a median and 95th percentile daily intake of 0.35 (my)g/kg bw and 0.71 (my)g/kg bw for exclusive uptake of MI and 0.64 (my)g/kg bw and 1.28 (my)g/kg bw for exclusive uptake of MCI/MI (3:1). We noted only slight variations over time for median exposures, but an increasing time trend in the 95th percentile exposure between 2006 and 2011 with a decrease in recent years, probably reflecting regulatory measures on MI and MCI/MI (3:1) in cosmetic products. Increasing knowledge on determinants of exposure to MI and/or MCI/MI (3:1) would be necessary to further lower exposure to these sensitizing compounds. © 2019 Elsevier Ltd. All rights reserved.
  • Veröffentlichung
    Human biomonitoring of per- and polyfluoroalkyl substances in German blood plasma samples from 1982 to 2019
    (2020) Göckener, Bernd; Bücking, Mark; Kolossa-Gehring, Marike; Weber, Till
    The findings of per- and polyfluoroalkyl substances (PFAS) in humans and the environment all over the world have raised concerns and public awareness for this group of man-made chemicals. In the last three decades, this led to different regulatory restrictions for specific PFAS as well as shifts in the production and usage of these substances. In this study, we analyzed the PFAS levels of 100 human blood plasma samples collected from 2009 to 2019 for the German Environmental Specimen Bank (ESB) to further elucidate the time course of exposure towards this substance group as shown by Schröter-Kermani et al., (2013) with samples from 1982 to 2010. A spectrum of 37 PFAS, including perfluorocarboxylic (PFCA) and -sulfonic acids (PFSA) as well as potential precursors and substitutes like ADONA, GenX or F-53B was analyzed by UHPLC coupled with high-resolution mass spectrometry. Validation was successful for 33 of the substances. The two legacy substances perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were detected in every sample of the 2009-2019 dataset and showed the highest concentrations with ranges of 0.27-14.0 ng/mL and 1.21-14.1 ng/mL, respectively. A significant portion of total PFOS analytes was present as branched isomers (mean: 34 +/- 7%). High detection frequencies of 95% and 82% were also found for perfluorohexane sulfonic acid (PFHxS) and perfluorononanoic acid (PFNA), respectively, but in lower concentrations (PFHxS:
  • Veröffentlichung
    Internal exposure of young German adults to di(2-propylheptyl) phthalate (DPHP): Trends in 24-h urine samples from the German Environmental Specimen Bank 1999-2017
    (2019) Schmidtkunz, Christoph; Gries, Wolfgang; Kolossa-Gehring, Marike; Weber, Till
    Di(2-propylheptyl) phthalate (DPHP) is used as a substitute for high molecular weight phthalates like di(2-ethylhexyl) phthalate (DEHP) which were subjected to authorization under REACh in 2015. An earlier study on the time trend of exposure in human 24-h urine samples from the German Environmental Specimen Bank has revealed that metabolites of DPHP emerged in 2009 and 2012 (Schütze et al., 2015). In order to better assess a potential trend and the present state of exposure to DPHP, we now measured 180 urine samples from the German Environmental Specimen Bank, 60 per year, collected in 2011, 2014 and 2017, randomized and blinded before analysis. Together with the previously analyzed samples, data for a total of 480 samples covering 19 years from 1999 to 2017 was thus generated. We were able to show that DPHP exposure of the studied population, university students from Münster (Northwestern Germany), has remained essentially constant since 2011, after a rapid increase starting around 2009. Even so, urinary metabolite concentrations were always in the low ppb or sub-ppb range, indicating that DPHP exposure of the general population is substantially lower than for other modern plasticizers, and far below levels currently regarded as critical. DPHP is a plasticizer which is mostly used in non-sensitive applications with little probability of close contact to humans. Still, we observed how temporal trends of DPHP exposure largely follow trends of DPHP consumption in the Western European market. Our results hence demonstrate the potential of biomonitoring to sensitively detect the effects of industrial product strategy on the environment, even when biomarkers are present only at trace level. © 2019 Elsevier GmbH. All rights reserved.