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Veröffentlichung Phylogeography of the invasive cyanobacterium Cylindrospermopsis raciborskii(2003) Neilan, B. A.; Saker, Martin L.; Fastner, J.; Törökné, A.; Burns, P. B.Veröffentlichung Effects of toxicants with different modes of action on Myriophyllum spicatum in test systems with varying complexity(2013)At the international workshop Aquatic Macrophyte Risk Assessment for Pesticides (AMRAP), it was noted that the EU risk assessment under the directive 91/414/EEC for herbicides, based only on algae and the monocotyledonous duckweed species Lemna sp., offers no certain protection against some growth regulating auxins. Therefore, AMRAP members proposed the introduction of the dicotyledonous water milfoil Myriophyllum as additional test species. This study was aimed to compare toxicity results from three test systems (TS) with varying complexity, namely Water TS, Sediment TS and Microcosm TS using Myriophyllum spicatum as test organism. As test substances, the photosynthesis inhibiting herbicide isoproturon, the growth regulating auxins fluroxypyr and 2,4-dichlorophenoxyacetic acid (2,4-D), and the non-specific acting toxicant 3,5-dichlorophenol (3,5-DCP) were chosen. It was assessed if and why the sensitivity of M. spicatum towards the four toxicants varied in the different test systems and if the addition of sucrose to the medium used in the Water TS had an effect on the sensitivity of Myriophyllum. All TS were suitable for detecting negative effects of toxicants with different modes of action on M. spicatum. The lowest variability of endpoints was found in the Water TS with lowest experimental complexity. For auxins, the endpoint weight did not result in robust EC50 values in all TS, whereas root related endpoints, which are also ecologically relevant, turned out to be very sensitive with low variance. Sucrose in the medium of the Water TS did not seem to influence the sensitivity of M. spicatum towards isoproturon and 3,5-DCP but may have increased the sensitivity of M. spicatum roots when exposed to 2,4-D. However, the findings of all TS resulted in similar risk estimations if root endpoints were not considered.
Quelle: http://www.sciencedirect.comVeröffentlichung Organic chemicals jeopardize the health of freshwater ecosystems on the continental scale(2014)Organic chemicals can contribute to local and regional losses of freshwater biodiversity and ecosystem services. However, their overall relevance regarding larger spatial scales remains unknown. Here, we present, to our knowledge, the first risk assessment of organic chemicals on the continental scale comprising 4,000 European monitoring sites. Organic chemicals were likely to exert acute lethal and chronic long-term effects on sensitive fish, invertebrate, or algae species in 14% and 42% of the sites, respectively. Of the 223 chemicals monitored, pesticides, tributyltin, polycyclic aromatic hydrocarbons, and brominated flame retardants were the major contributors to the chemical risk. Their presence was related to agricultural and urban areas in the upstream catchment. The risk of potential acute lethal and chronic long-term effects increased with the number of ecotoxicologically relevant chemicals analyzed at each site. As most monitoring programs considered in this study only included a subset of these chemicals, our assessment likely underestimates the actual risk. Increasing chemical risk was associated with deterioration in the quality status of fish and invertebrate communities. Our results clearly indicate that chemical pollution is a large-scale environmental problem and requires far-reaching, holistic mitigation measures to preserve and restore ecosystem health. Quelle: www.pnas.orgVeröffentlichung Gastrointestinal absorption of uranium compounds A review(2015) Konietzka, RainerUranium occurs naturally in soil and rocks, and therefore where it is present in water-soluble form it also occurs naturally in groundwater as well as in drinking water obtained from groundwater. Animal studies suggest that the toxicity of uranium is mainly due to its damage to kidney tubular cells following exposure to soluble uranium compounds. The assessments of the absorption of uranium via the gastrointestinal tract vary, and this has consequences for regulation, in particular the derivation of e.g. drinking water limit values. Absorption rates vary according to the nature and solubility of the compound in which uranium is presented to the test animals and depending on the animal species used in the test. No differences for sex have been observed for absorption in either animals or humans. However, human biomonitoring data do show that boys excrete significantly more uranium than girls. In animal studies neonates took up more uranium than adults or older children. Nutritional status, and in particular the iron content of the diet, have a marked influence on absorption, and higher uranium levels in food intake also appear to increase the absorption rate. If the pointers to an absorption mechanism competing with iron are correct, these mechanisms could also explain the relatively high concentration and chemical toxicity of uranium in the kidneys. It is here (and in the duodenum) that divalent metal transporter 1 (DMT1), which is primarily responsible for the passage of iron (or uranium?) through the cell membranes, is most strongly expressed.Quelle: http://www.sciencedirect.comVeröffentlichung Glyceria maxima as new test species for the EU risk assessment for herbicides: a microcosm study(2015)In its recent guidance document on tiered risk assessment for plant protection products for aquatic organisms, the EuropeanFood SafetyAuthority (EFSA) proposed to use Glyceriamaximaas monocotyledonous grass species for the testing of special herbicide groups. However, published toxicity data for this species is very limited and there is no test guideline for Glyceriasp. For this reason a microcosm study was conducted in order to gain experience on the degree of sensitivity of G.maximato the herbicidal substances clodinafop-propargyl (grass herbicide) and fluroxypyr (auxin) in comparison to the already established test organism water milfoil Myriophyllum spicatumand the duckweed species Landoltiapunctata. Five concentrations without replicates were tested for each test substance using 10 microcosms and three microcosms served as controls. The experiment was run for 8 weeks. Morphological endpoints were used to determine growth and EC50values. The results show that M. spicatumwas most sensitive to fluroxypyr (37 days EC50for roots: 62 ng/L) and G.maximamost sensitive to clodinafop-propargyl (22 days EC50for total shoot length: 48 ng/L) whereas the duckweed species was considerable less sensitive. Hence, G.maximaturns out to be a good candidate for testing grass specific herbicides, supporting its inclusion as an additional macrophyte test for the risk assessment of herbicides as proposed by the EFSA. Quelle: http://link.springer.comVeröffentlichung Integrated in silico strategy for PBT assessment and prioritization under REACH(2016) Pizzo, Fabiola; Lombardo, Anna; Manganaro, Alberto; Brandt, Marc; Cappelli, Claudia I.; Petoumenou, Maria I.; Albanese, Federica; Roncaglioni, Alessandra; Benfenati, EmilioChemicals may persist in the environment, bioaccumulate and be toxic for humans and wildlife, posing great concern. These three properties, persistence (P), bioaccumulation (B), and toxicity (T) are the key targets of the PBT-hazard assessment. The European regulation for the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) requires assessment of PBT-properties for all chemicals that are produced or imported in Europe in amounts exceeding 10 tonnes per year, checking whether the criteria set out in REACH Annex XIII are met, so the substance should therefore be considered to have properties of very high concern. Considering how many substances can fall under the REACH regulation, there is a pressing need for new strategies to identify and screen large numbers fast and inexpensively. An efficient non-testing screening approach to identify PBT candidates is necessary, as a valuable alternative to money- and time-consuming laboratory tests and a good start for prioritization since few tools exist (e.g. the PBT profiler developed by USEPA).
The aim of this work was to offer a conceptual scheme for identifying and prioritizing chemicals for further assessment and if appropriate further testing, based on their PBT-potential, using a non-testing screening approach. We integrated in silico models (using existing and developing new ones) in a final algorithm for screening and ranking PBT-potential, which uses experimental and predicted values as well as associated uncertainties. The Multi-Criteria Decision-Making (MCDM) theory was used to integrate the different values. Then we compiled a new set of data containing known PBT and non-PBT substances, in order to check how well our approach clearly differentiated compounds labeled as PBT from those labeled as non-PBT. This indicated that the integrated model distinguished between PBT from non-PBT compounds.
Quelle: http://www.sciencedirect.comVeröffentlichung Health-based evaluation of chemical emissions to indoor air from construction products: Development and application of the EU-LCI harmonisation framework(2016) Crump, Derrick; Brouwere, Katleen De; Däumling, Christine; Harrison, Paul; Scutaru, Ana Maria; Wolkoff, PederVeröffentlichung Rating the risks of anticoagulant rodenticides in the aquatic environment(2018) Regnery, Julia; Friesen, Anton; Geduhn, Anke; Petersohn, Eleonora; Schmolz, ErikAnticoagulant rodenticides are used worldwide to control commensal rodents for hygienic and public health reasons. As anticoagulants act on all vertebrates, risk is high for unintentional poisoning of terrestrial and aquatic wildlife. Causative associations have been demonstrated for the unintended poisoning of terrestrial nontarget organisms. However, behavior and fate of anticoagulant rodenticides in the aquatic environment have received minimal attention in the past despite considerable acute toxicity of several anticoagulants to aquatic species such as fish. In light of recent regulatory developments in the European Union concerning rodenticides, we critically review available information on the environmental occurrence, fate, and impact of anticoagulant rodenticides in the aquatic environment and identify potential risks and routes of exposure as well as further research needs. Recent findings of anticoagulant rodenticides in raw and treated wastewater, sewage sludge, estuarine sediments, suspended particulate matter, and liver tissue of freshwater fish in the low ng/L and Ìg/kg range, respectively, demonstrate that the aquatic environment experiences a greater risk of anticoagulant rodenticide exposure than previously thought. While the anticoagulant's mechanism of action from the molecular through cellular levels is well understood, substantial data gaps exist regarding the understanding of exposure pathways and potential adverse effects of chronic exposure with multiple active ingredients. Anticoagulants accumulating in aquatic wildlife are likely to be transferred in the food chain, causing potentially serious consequences for the health of wildlife and humans alike. © 2018, Springer Nature Switzerland AG.Veröffentlichung Persistent, mobile and toxic substances in the environment: a spotlight on current research and regulatory activities(2020) Rüdel, Heinz; Körner, Wolfgang; Letzel, Thomas; Neumann, MichaelCertain persistent and polar substances may pose a hazard to drinking water resources. To foster the knowledge exchange in this field the Working Group Environmental Monitoring of the German Chemical Society (GDCh) Division Environmental Chemistry and Ecotoxicology discussed at their meeting in December 2018 the significance and relevance of persistent, mobile and toxic chemicals (PMT substances) in the environment. Five oral contributions highlighted not only various aspects such as the identification of potential PMT substances based on certain properties and their possible regulation under the European REACH regulation, but also current developments in the analysis of PMT substances and results from environmental monitoring. The data presented prove that many persistent and mobile substances can be detected in surface waters. Once detected, it can be complex and costly to identify sources and reduce inputs, as a case study on 1,4-dioxane in Bavarian surface waters shows. The same applies to the removal of polar substances from raw water for drinking water production. Today, scientific advances in analytical methods make it easier to identify and quantify even very polar substances in water samples. In addition to the targeted analysis of critical chemicals, non-target screening is playing an increasingly important role. This opens up the possibility of detecting substances in water samples that have not previously been investigated in routine monitoring and testing their relevance for humans and the environment. However, the list of potentially occurring PM substances that have not yet been investigated is still very long. Further methodological improvements seem necessary here. In view of the evidence for the presence of PMT substances in the environment (e.g., trifluoroacetic acid and 1,4-dioxane) and the potential risks for drinking water abstraction, it seems important under consideration of the precautionary principle to identify and prioritise relevant REACH-registered substances. The assessment should be based on the intrinsic properties and the emission potential of the compounds. The implementation of a detailed proposal made at European level to regulate PMT and very persistent and very mobile (vPvM) substances in the context of REACH would ensure that chemicals identified as being substances of very high concern according to the PMT and vPvM criteria are subject to authorisation in future. © The Author(s) 2020Veröffentlichung Glyphosate and aminomethylphosphonic acid (AMPA) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)(2021) Conrad, André; Kolossa-Gehring, Marike; Lemke, Nora; Murawski, Aline; Schmied-Tobies, Maria Irene HildeSince the 1970s, glyphosate has become the most used herbicide of the world. The general population is ubiquitously exposed to glyphosate. Its long-term toxicity, carcinogenic potential and other health effects are controversially discussed. Even though the possible health impacts of glyphosate are of global concern, no population-wide monitoring of glyphosate was done yet. This study presents the worldwide first population-representative data on glyphosate and its metabolite aminomethylphosphonic acid (AMPA) for children and adolescents. 2144 first-morning void urine samples of 3-17-year-old children and adolescents living in Germany were analysed for concentrations of glyphosate and AMPA in the German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). In 52 % of the samples (46 % for AMPA) the urinary glyphosate concentrations were above the limit of quantification of 0.1 (microgramm)/L. The geometric mean concentrations were 0.107 (microgramm)/L (0.090 (microgramm)/gcreatinine) for glyphosate and 0.100 (microgramm)/L (0.085 (microgramm)/gcreatinine) for AMPA. No clear association between exposure to glyphosate or AMPA and vegetarian diet or consumption of cereals, pulses, or vegetables could be identified. The low quantification rate and the 95th percentiles for glyphosate and AMPA of around 0.5 (microgramm)/L demonstrate an overall low exposure of the young population in Germany. Quelle: © Elsevier 2021