Person: Conrad, André
Lade...
E-Mail-Adresse
Geburtsdatum
1975
Forschungsvorhaben
Organisationseinheiten
Berufsbeschreibung
Nachname
Conrad
Vorname
André
Name
28 Ergebnisse
Suchergebnisse
Gerade angezeigt 1 - 10 von 28
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, TillAs 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 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 24-h urine samples of the German Environmental Specimen Bank (ESB) from 1988 to 2015 and a comparison with US NHANES data from 1999 to 2012(2017) Koch, Holger M.; Apel, Petra; Schütze, Andre; Conrad, André; Pälmke, Claudia; Kolossa-Gehring, Marike; Brüning, Thomas; Rüther, MariaThe German Environmental Specimen Bank (ESB) continuously collects 24-h urine samples since theearly 1980s in Germany. In this study we analyzed 300 urine samples from the years 2007 to 2015 for 21phthalate metabolites (representing exposure to 11 parent phthalates) and combined the data with twoprevious retrospective measurement campaigns (1988 to 2003 and 2002 to 2008). The combined datasetcomprised 1162 24-h urine samples spanning the years 1988 to 2015. With this detailed set of humanbiomonitoring data we describe the time course of phthalate exposure in Germany over a time frame of27 years. For the metabolites of the endocrine disrupting phthalates di(2-ethylhexyl) phthalate (DEHP),di-n-butyl phthalate (DnBP) and butylbenzyl phthalate (BBzP) we observed a roughly ten-fold decline inmedian metabolite levels from their peak levels in the late 1980s/early 1990s compared to most recentlevels from 2015. Probably, bans (first enacted in 1999) and classifications/labelings (enacted in 2001 and2004) in the European Union lead to this drop. A decline in di-isobutyl phthalate (DiBP) metabolite levelsset in only quite recently, possibly due to its later classification as a reproductive toxicant in the EU in 2009.In a considerable number of samples collected before 2002 health based guidance values (BE, HBM I) havebeen exceeded for DnBP (27.2%) and DEHP (2.3%) but also in recent samples some individual exceedancescan still be observed (DEHP 1.0%). A decrease in concentration for all low molecular weight phthalates,labelled or not, was seen in the most recent years of sampling. For the high molecular weight phthalates,DEHP seems to have been substituted in part by di-isononyl phthalate (DiNP), but DiNP metabolite levelshave also been declining in the last years. Probably, non-phthalate alternatives increasingly take overfor the phthalates in Germany. A comparison with NHANES (National Health and Nutrition ExaminationSurvey) data from the United States covering the years 1999 to 2012 revealed both similarities anddifferences in phthalate exposure between Germany and the US. Exposure to critical phthalates hasdecreased in both countries with metabolite levels more and more aligning with each other, but highmolecular weight phthalates substituting DEHP (such as DiNP) seem to become more important in theUS than in Germany.
© 2016 Elsevier GmbH. All rights reservedVeröffentlichung 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 A human biomonitoring study assessing glyphosate and Aminomethylphosphonic Acid (AMPA) exposures among farm and non-farm families(2022) Connolly, Alison; Koch, Holger Martin; Bury, Daniel; Conrad, André; Kolossa-Gehring, Marike; Murawski, AlineGlyphosate-based pesticides are the highest-volume used herbicides worldwide. International concerns regarding the potential human adverse effects of glyphosate exposures have heightened since IARC classified glyphosate as probably carcinogenic to humans. Human biomonitoring (HBM) studies have identified ubiquitous exposure to glyphosate and its main breakdown product, aminomethylphosphonic acid (AMPA), from environmental exposures. The IMAGE research project aimed to investigate farm and non-farm families' exposure to glyphosate while aligning with the Human Biomonitoring for Europe (HBM4EU) initiative. The study recruited non-farm and farm families (who use glyphosate on their farms). Each family member provided a urine sample that was analysed using gas chromatography coupled with tandem mass spectrometry, with a limit of quantification of 0.05 (micro)g/L for glyphosate and AMPA. In addition to general information on background exposures in farm and non-farm families, we investigated relationships in exposure between families and family members. We recruited 68 families, including 54 non-farm and 14 farm families (180 vs. 45 individuals). Some pesticide users (n = 14, all male farmers) had slightly elevated AMPA levels compared to other adult participants but, overall, we observed no significant differences between farm and non-farm families. The main metabolite, AMPA, was quantifiable in twice as many samples as glyphosate (61% vs. 32%), with a maximum concentration of 7.24 (micro)g/L vs. 3.21 (micro)g/L. Compared to previous studies, exposure levels were relatively low and far below current health-based guidance values (3% or less for glyphosate and AMPA). Study results suggest potential exposures from residential co-exposures or living with a pesticide user. This is the first study internationally to investigate glyphosate and AMPA across family members (farm and non-farm). We found comparably low glyphosate and AMPA exposures among these families. These results enhance our understanding of glyphosate exposures for different demographic groups and contribute to the scientific knowledge on exposures required for regulatory risk assessments and the re-evaluation of glyphosate in 2022 by the European Commission. © 2022 by the authorsVeröffentlichung Developing human biomonitoring as a 21st century toolbox within the European exposure science strategy 2020-2030(2022) Jeddi, Maryam Zare; Conrad, André; Hopf, Nancy B.; Louro, Henriqueta; Kolossa-Gehring, MarikeHuman biomonitoring (HBM) is a crucial approach for exposure assessment, as emphasised in the European Commissionâ€Ìs Chemicals Strategy for Sustainability (CSS). HBM can help to improve chemical policies in five major key areas: (1) assessing internal and aggregate exposure in different target populations; 2) assessing exposure to chemicals across life stages; (3) assessing combined exposure to multiple chemicals (mixtures); (4) bridging regulatory silos on aggregate exposure; and (5) enhancing the effectiveness of risk management measures. In this strategy paper we propose a vision and a strategy for the use of HBM in chemical regulations and public health policy in Europe and beyond. We outline six strategic objectives and a roadmap to further strengthen HBM approaches and increase their implementation in the regulatory risk assessment of chemicals to enhance our understanding of exposure and health impacts, enabling timely and targeted policy interventions and risk management. These strategic objectives are: 1) further development of sampling strategies and sample preparation; 2) further development of chemical-analytical HBM methods; 3) improving harmonisation throughout the HBM research life cycle; 4) further development of quality control / quality assurance throughout the HBM research life cycle; 5) obtain sustained funding and reinforcement by legislation; and 6) extend target-specific communication with scientists, policymakers, citizens and other stakeholders. HBM approaches are essential in risk assessment to address scientific, regulatory and societal challenges. HBM requires full and strong support from the scientific and regulatory domain to reach its full potential in public and occupational health assessment and in regulatory decision-making. © 2022 The AuthorsVeröffentlichung 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 Benefits of cooperation among large-scale cohort studies and human biomonitoring projects in environmental health research: An exercise in blood lead analysis of the Environment and Child Health International Birth Cohort Group(2019) Nakayama, Shoji F.; Conrad, André; Espina, Carolina; Kamijima, Michihiro; Kolossa-Gehring, Marike; Murawski, AlineA number of prospective cohort studies are ongoing worldwide to investigate the impact of foetal and neonatal exposures to chemical substances on child health. To assess multiple exposure (mixture) effects and low prevalence health outcomes it is useful to pool data from several studies and conduct mega-data-analysis. To discuss a path towards data harmonization, representatives from several large-scale birth cohort studies and a biomonitoring programme formed a collaborative group, the Environment and Child Health International Birth Cohort Group (ECHIBCG). In this study, an intra-laboratory trial was performed to harmonize existing blood lead measurements within the groups' studies. Then, decentralized analyses were conducted in individual countries' laboratories to evaluate blood lead levels (BLL) in each study. The measurements of pooled BLL samples in French, German and three Japanese laboratories resulted in an overall mean blood lead concentration of 8.66 ng¯1 (95% confidence interval: 8.59-8.72 ng¯1) with 3.0% relative standard deviation. Except for China's samples, BLL from each study were comparable with mean concentrations below or close to 10ng¯1. The decentralized multivariate analyses revealed that all models had coefficients of determination below 0.1. Determinants of BLL were current smoking, age >35 years and overweight or obese status. The three variables were associated with an increase in BLL in each of the five studies, most strongly in France by almost 80% and the weakest effect being in Norway with only 15%; for Japan, with the far largest sample (~18,000), the difference was 36%. This study successfully demonstrated that the laboratory analytical methods were sufficiently similar to allow direct comparison of data and showed that it is possible to harmonize the epidemiological data for joint analysis. This exercise showed the challenges in decentralized data analyses and reinforces the need for data harmonization among studies. © 2019 The Authors. Published by Elsevier GmbH.
- «
- 1 (current)
- 2
- 3
- »