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Daily intake and hazard index of parabens based upon 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

Moos, Rebecca K.; Apel, Petra; Schröter-Kermani, Christa; Kolossa-Gehring, Marike; Brüning, Thomas; Koch, Holger M. Journal of Exposure Science and Environmental Epidemiology , online 30. November 2016 In recent years, exposure to parabens has become more of a concern because of evidence of ubiquitous exposure in the general population, combined with evidence of their potency as endocrine disruptors. New human metabolism data from oral exposure experiments enable us to back calculate daily paraben intakes from urinary paraben levels. We report daily intakes (DIs) for six parabens based on 660 24 h urine samples from the German Environmental Specimen Bank collected between 1995 and 2012. Median DI values ranged between 1.1 μg/kg bw/day for iso-butyl paraben and 47.5 μg/kg bw/day for methyl paraben. The calculated DIs were compared with acceptable levels of exposure to evaluate the hazard quotients (HQs) that indicate that acceptable exposure is exceeded for values of >1. Approximately 5% of our study population exceeded this threshold for individual paraben exposure. The hazard index (HI) that takes into account the cumulative risk of adverse estrogenic effects was 1.3 at the 95th percentile and 4.4 at maximum intakes, mainly driven by n-propyl paraben exposure. HI values of >1 indicate some level of concern. However, we have to point out that we applied most conservative assumptions in the HQ/HI calculations. Also, major exposure reduction measures were enacted in the European Union after 2012. doi:10.1038/jes.2016.65 Verwandte Publikation: Parabens in 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

Recent findings of halogenated flame retardants (HFR) in the German and Polar environment

Dreyer, Annekatrin; Neugebauer, Frank; Lohmann, Nina; Rüdel, Heinz; Teubner, Diana; Grotti, Marco; Rauert, Caren; Koschorreck, Jan Environmental Pollution 253 (2019), 850-863; online 17. Juli 2019 To get an overview about distribution, levels and temporal trends of polybrominated diphenyl ethers (PBDE) and halogenated flame retardants (HFR) of emerging concern, different types of environmental samples archived in the German Environment Specimen Bank as well as fish filet samples from the Arctic (n = 13) and Antarctica (n = 5) were analysed for 43 substances (24 PBDE, 19 HFR) using a multi-column clean-up and GC-API-MS/MS or GC-MS. Sample types were herring gull egg (n = 3), blue mussel (n = 3) and eelpout filet (n = 3) from the German North- and Baltic Sea, bream filet (n = 7), zebra mussel (n = 6) and suspended particulate matter (SPM, n = 7) from German freshwater ecosystems as well as tree leaves (n = 9)/shoots (n = 10), soil (n = 4), earthworm (n = 4) and deer liver (n = 7) as representatives of German terrestrial ecosystems. PBDE and emerging HFR were present in each investigated matrices from Germany and Polar regions showing their widespread distribution. The presence in Arctic and Antarctic fish samples confirms their long-range transport potential. Average concentrations of total emerging HFR were highest in SPM (26 ng g -1 dry weight (dw)), zebra mussel (10 ng g -1 dw) and herring gull egg (2.6 ng g -1 dw). Lowest levels were measured in fish filet samples from Antarctica (0.02 ng g -1 dw). Average total PBDE concentrations were highest in bream filet (154 ng g -1 ), herring gull egg (61 ng g -1 dw), SPM (21 ng g -1 dw), and zebra mussel 18 (ng g -1 ) and lowest in deer liver (0.04 ng g -1 dw). The patterns of non-fauna terrestrial samples (leaves, shoots, soil) as well as SPM were dominated by DBDPE and BDE209. Elevated proportions of DPTE and in most cases the absence of DBDPE characterized all fauna samples with the exception of Polar samples. Overall, emerging HFR appeared to be less bioaccumulative than PBDE. Temporal trends were generally decreasing with few exceptions such as DBDPE. doi: 10.1016/j.envpol.2019.07.070

Modeling the role of the last ice age for the present and future sea-level contribution from Antarctica (SPP-ANTARCTICA)

Das Projekt "Modeling the role of the last ice age for the present and future sea-level contribution from Antarctica (SPP-ANTARCTICA)" wird vom Umweltbundesamt gefördert und von Potsdam-Institut für Klimafolgenforschung e.V. durchgeführt. The project will encompass the numerical simulation of at least four glacial cycles of the Antarctic sheet-shelf system using the Parallel Ice Sheet Model (PISM). The objective of the research plan is to determine the role of the past development of the Antarctic Ice Sheet for its sea-level contribution of the past and future century. To this end we investigate the influence of past climate evolution, especially the last deglaciation, on its present dynamic state: The ongoing changes in terms of mass balance, disregarding anthropogenic climate change, during the 20th and 21st centuries are influenced by the history of the advance and retreat of the ice during the last glacial cycles. Instead of aiming at a best-guess simulation, we will work on providing an ensemble of model simulations that incorporates uncertainties from climate boundary conditions and internal process-modeling and ice parameter choices. Apart from answering the above mentioned research question concerning the influence of the history of the ice sheet on its present day dynamics, we will also take an important step towards a new generation of projections of future ice discharge from Antarctica: It is important to know how much sea-level contribution, if any, is not caused by anthropogenic climate change. The program encompasses the development and short-term testing of physical improvements to the model that are needed in order to perform four glacial cycles (4GC) simulations and to provide a comprehensive ensemble. The currently implemented climate boundary conditions, both for the upper surface of the ice sheet and the underside of the ice shelves in contact with the ocean, will be examined and expanded to be suitable for 4GC-simulations. Process-based model components, concerning the numerical representation of the transition zone between ice sheet and ice shelf will be evaluated and improved. High-resolution nested simulation approaches will be developed for PISM in order to better resolve these crucial zones in order the further close the gap between finite differences models like PISM using shallow approximations of the stress balance and higher-order models. Sensitivity tests within 4GC-simulations will shed light on how the above mentioned new methods, climate boundary conditions in general and internal model parameters, influence the 4GC-simulation and ultimately the modeled present day state. An ensemble selection process will take place, excluding those parameter and climate-boundary combinations that are not conform to available geologic data for the past and observations of the present day state of the Antarctic ice sheet. This can be thought of as a blind selection of the dynamic present-day state of the ice sheet. By that dynamic state we mean the responsiveness of the modeled ice sheet to external forcing, which can vary drastically among a set of modeled ice sheets that are quite similar with respect to vertical and horizontal ice extent. (abridged text)

Global mass balance of persistent semi-volatile organic compounds: an approach with PCB as an indicator

Das Projekt "Global mass balance of persistent semi-volatile organic compounds: an approach with PCB as an indicator" wird vom Umweltbundesamt gefördert und von Universität Kiel, Institut für Meereskunde, Abteilung für Meereschemie durchgeführt. General Information: Several studies show that a large number of semi-volatile organic compounds (SOCs), and among them polychlorinated biphenyls (PCBs), are global pollutants. Atmospheric concentrations of PCBs in remote locations have not decreased or decreased very little since the 1970s, despite regulations that have drastically decreased the production of PCBs. This is a cause of concern since some PCB congeners are likely to cause toxicological effects at the present levels. Are PCB concentrations maintained by continuos diffuse emissions or are old emissions of PCBs being recycled? What is the rate of decrease in remote areas of the globe for different PCB congeners? The proposed project aims to address and quantify the major global loss rates which will also help answer to the question: where will the PCBs end up? In deep-sea water? Coastal sediments? Soil? Or chemically transformed to other substances? Preliminary global mass balance calculations point to the fact that all of these processes may be of significance for the environments capacity to remove pollutants on global scale. The proposed project will therefore be divided into sub-projects focusing on these different processes. Additional sub-projects will be modelling and compilation of data from other sub-projects, emission estimates for the completion of the global mass balance, and a quality assurance program to ensure the quality of all data generated within the project. GLOBAL-SOC involves several aspects of method development and innovative approaches to the assessment of SOCs fate in a global perspective. These issues are of fundamental concern for the environmental policy of the European Union and its individual member states. SOCs are typical transboundary pollutants which must be addressed in international collaborations. This project is focused on PCBs because they are well studied in many aspects, readily analysed in any matrix even at remote locations and since most of the emissions have probably been reduced, the part recycled in the environment can be studied. PCBs in this study shall be seen as a 'model compound group' to give us information about SOCs in general, in particular those SOCs that are in use today or in use until recently, in Europe and in other parts of the world e.g. polybrominated flame retardants, polychlorinated naphtalenes, chloroparaffins, DDT and other chlorinated pesticides. Prime Contractor: Stockholms Universitet, Department of Zoology, Institut foer Tillaempad Miljoeforskning; Stockholm; Sweden.

Short-term effects of air pollution on health: a european approach to methodology, dose response assessment and evaluation of public health significance

Das Projekt "Short-term effects of air pollution on health: a european approach to methodology, dose response assessment and evaluation of public health significance" wird vom Umweltbundesamt gefördert und von Didier-Werke, Anlagentechnik durchgeführt. General Information: In the context of recent publications from North America, indicating that moderate and low levels of air pollution have measurable short-term effects on mortality and morbidity, and the concern caused in the public and regulatory bodies, the APHEA (Short-term effects of Air Pollution on Heath: a European Approach) project investigated the issue in 15 European cities, within the Environment 1991-94 Programme. The combined analyses showed that particulate matter, SO2 and ozone were associated with statistically significant increases in total and cause specific daily mortality (an increase of 50 kg/m3 in one pollutant level was associated with 1-5 per cent increase in mortality). Particulate matter and ozone levels were found associated with hospital respiratory and COPD admissions (a 50kg/m3 increase in the pollutant level was followed by a 1-4 per cent increase in the daily number of admissions) while NO2 levels appeared associated with the number of asthma admissions. Other interesting results referred to regional differences and effect modification by season and by other pollutants. The present proposal has four objectives: 1. To investigate dose-response curves for air pollutants (particulate matter, SO2,NO2,Ozone, CO) -mortality (total, cardiovascular and respiratory) associations in 32 European cities/areas and air pollutants-hospital respiratory admissions in 7 areas, spread in 17 countries; 2. To address the problem of mortality displacement (i.e. how premature are the deaths caused by air-pollution) which is particularly important for evaluating the public health significance of the short-term air pollution health effects; 3. To investigate further regional differences in air pollutants- health associations; and 4. To evaluate results from Europe together with those from the U.S. in collaboration with a starting similar U.S. project. Extended and updated data files (up to 1995 or 96) will be used. The project is structured in Work Packages. In the initial stage (6 months) all Partners will compile their data files and send them to the four Partners who will be responsible for the analyses of individual data sets (13 months) and for the different aspects of the joint analyses (8 months). The next stages will be a collaboration with U.S. researchers (4 months) and the preparation of Reports and manuscripts (5 months). The project will be managed by a Steering Committee, while a Statistical group will be formed to decide on methodological aspects. The total duration of the project will be 36 months with a probable starting date 1/10/97. It is expected that the results will provide important input for public health protection policies and regulations concerning air quality. Prime Contractor: National and Kapodistrian University of Athens, Medical School, Department of Hygiene and Epidemiology; Athens-Goudi; Greece.

Energy and environment - optimal control strategies for reducing emissions from energy productions and energy use

Das Projekt "Energy and environment - optimal control strategies for reducing emissions from energy productions and energy use" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Kernenergetik und Energiesysteme durchgeführt. Objective: Due to the complexity of the energy system, the analysis and the identification of efficient emissions reduction strategies require adequate methodological instruments. The development of our energy-environment model based on efom 12c model that describes the energy systems in the different ec countries in a detailed form is a promising starting point for the analysis of the following problems and questions: -the future development of air pollution emissions from energy. -impacts of further improvement of energy efficiency and of a possible increase of the market share for solid fuels. -effects of emission reduction measures and policies. -cost-optimal emission reduction strategies. -waste management for the follow-up products. -contribution of interregional measures. General information: the energy model efom developed within the eg-project on 'energy systems analysis' which has been extended by an environment-module has already been used as a pilot model for an analysis of cost-optimal strategies to reduce so2-,nox- and dust-emissions in connection with energy production and energy use in the frg. This phase of the project was carried out by three different institutes (ike, iip, ste) each participating according to its specialisation. Ike will be responsible for the overall management of the project in frg. The next phase concerns the interrelationship of 'energy and environment'' to be studied on a European level. A cooperation between institutes of all ec countries has been set up to demonstrate the usefulness of the developed model. The present contract concerns essentially the extension of the environmental study to the ec and the contribution of ike for a successful accomplishment of such project. Achievements: As an important step towards a broader international analysis of energy and environmental issues, the effects of environmental control measures for the reduction of sulphur dioxide and nitrogen dioxide have been studied in detail. The analysis entails all sectors of the economy system. Acid pollution has been the main area of interest since concern in Europe has grown in the past few years as a result of observed forest damage and also because of the reduction of fish populations in lakes. Acid precipitation is considered a possible contributory cause.

Daily intake and hazard index of parabens based upon 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

In recent years, exposure to parabens has become more of a concern because of evidence of ubiquitous exposure in the general population, combined with evidence of their potency as endocrine disruptors. New human metabolism data from oral exposure experiments enable us to back calculate daily paraben intakes from urinary paraben levels. We report daily intakes (DIs) for six parabens based on 660 24h urine samples from the German Environmental Specimen Bank collected between 1995 and 2012. Median DI values ranged between 1.1Ţg/kg bw/day for iso-butyl paraben and 47.5Ţg/kg bw/day for methyl paraben. The calculated DIs were compared with acceptable levels of exposure to evaluate the hazard quotients (HQs) that indicate that acceptable exposure is exceeded for values of >1. Approximately 5% of our study population exceeded this threshold for individual paraben exposure. The hazard index (HI) that takes into account the cumulative risk of adverse estrogenic effects was 1.3 at the 95th percentile and 4.4 at maximum intakes, mainly driven by n-propyl paraben exposure. HI values of >1 indicate some level of concern. However, we have to point out that we applied most conservative assumptions in the HQ/HI calculations. Also, major exposure reduction measures were enacted in the European Union after 2012. Quelle: www.nature.com

Recent findings of halogenated flame retardants (HFR) in the German and Polar environment

To get an overview about distribution, levels and temporal trends of polybrominated diphenyl ethers (PBDE) and halogenated flame retardants (HFR) of emerging concern, different types of environmental samples archived in the German Environment Specimen Bank as well as fish filet samples from the Arctic (n=13) and Antarctica (n=5) were analysed for 43 substances (24 PBDE, 19 HFR) using a multi-column clean-up and GC-API-MS/MS or GC-MS. Sample types were herring gull egg (n=3), blue mussel (n=3) and eelpout filet (n=3) from the German North- and Baltic Sea, bream filet (n=7), zebra mussel (n=6) and suspended particulate matter (SPM, n=7) from German freshwater ecosystems as well as tree leaves (n=9)/shoots (n=10), soil (n=4), earthworm (n=4) and deer liver (n=7) as representatives of German terrestrial ecosystems. PBDE and emerging HFR were present in each investigated matrices from Germany and Polar regions showing their widespread distribution. The presence in Arctic and Antarctic fish samples confirms their long-range transport potential. Average concentrations of total emerging HFR were highest in SPM (26 ng g-1 dry weight (dw)), zebra mussel (10 ng g-1 dw) and herring gull egg (2.6 ng g-1 dw). Lowest levels were measured in fish filet samples from Antarctica (0.02 ng g-1 dw). Average total PBDE concentrations were highest in bream filet (154 ng g-1), herring gull egg (61 ng g-1 dw), SPM (21 ng g-1 dw), and zebra mussel 18 (ng g-1) and lowest in deer liver (0.04 ng g-1 dw). The patterns of non-fauna terrestrial samples (leaves, shoots, soil) as well as SPM were dominated by DBDPE and BDE209. Elevated proportions of DPTE and in most cases the absence of DBDPE characterized all fauna samples with the exception of Polar samples. Overall, emerging HFR appeared to be less bioaccumulative than PBDE. Temporal trends were generally decreasing with few exceptions such as DBDPE. Quelle: https://www.sciencedirect.com

Temporal trends of lipophilic organic contaminants in blue mussel (1994-2017) and eelpout (1994-2017) from the southern Baltic Sea

A time-trend study was carried out for two important Baltic Sea species, blue mussel (1994-2017, 11 samples) and eelpout (1994-2017, 11 samples), to track the changes in levels of regulated persistent organic pollutants (POPs) and show potential increases in the levels of the contaminants of emerging concern (CECs). It was carried out utilizing gas chromatography-high-resolution mass spectrometry (GC-HRMS) based non-target screening (NTS). Data were acquired in two modes - electron ionization (EI) and electron capture negative ion chemical ionization (ECNI) to widen the contaminant coverage, and treated using a fast semi-automated NTS data processing workflow. The study revealed that >250 tentatively identified compounds show statistically significant temporal trends in Baltic blue mussel and eelpout. A large number of regulated substances, including but not limited to PCBs, DDTs and other organochlorine pesticides (OCPs), chlorobenzenes, and many polybrominated diphenyl ethers (PBDEs), showed significant declining trends, as was expected. Their rates of decline were in good agreement with previously reported data. In contrast, increasing trends were observed for many CECs, some polycyclic aromatic compounds (PAHs), and hydrocarbons. The CEC group included, among others, four compounds, namely, one personal care product ingredient, 2-ethylhexyl stearate, one brominated compound 1,2,3,5-tetrabromobenzene and two intermediates 4-isopropoxyaniline and bilobol dimethyl ether, that were reported in marine biota for the first time to the best of our knowledge. Several compounds, including four CECs and two unknown brominated compounds, showed levels considerably higher than the common legacy pollutants (CB-153 and BDE-99), which might be taken into consideration for future monitoring and risk assessment. In addition, this work revealed the presence of a plethora of organoiodinated compounds that exhibited statistically significant temporal trends in the samples under study, which could be of future interest. © 2023 The Authors

Participatory technology development to manage cocoa pests and diseases in smallholder cocoa plantations in souther Cameroon

Das Projekt "Participatory technology development to manage cocoa pests and diseases in smallholder cocoa plantations in souther Cameroon" wird vom Umweltbundesamt gefördert und von Georg-August-Universität Göttingen, Department für Nutzpflanzenwissenschaften, Abteilung Agrarentomologie durchgeführt. Cocoa (Theobroma cacao L.) is the most important export crop and main source of foreign exchange in Cameroon. 400 000 households with poor resources to improve or expand their farms dominate the cocoa industry. Mirids (Salhbergella singularis Hagh.) is the most important pest causing 30 to 40 percent annual loss and tree death in severe cases. Most of the recommendations extended to cocoa farmers on the control of mirids have become inadequate and unsustainable because they have developed resistance to all pesticides used by farmers. The environmental concern, demand of consumers and regulatory authorities of cocoa free of pesticide residues combine to decrease production levels. Projections are made on integrated crop management (ICM) practices that will minimize the use of environmental hazardous pesticides, and sound socio-economic considerations that could promote sustainable cocoa production. At present, research on integrated management of mirids of cacao, although engaged in Cameroon, accounts variable degree of results. Some innovating research activities let predict, in theory, an improvement of control measures against mirids in the future, but with limited application. Consequently, the solution lies in an integrated approach to the management of cocoa agroforests through easy recommendations adapted to each locality. Such mode of action must be based on a total knowledge of the pest concerned and the agroecosystems in which they prevail.

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