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Majadahonda, Spain

Fernandez M.F.,University of Granada | Fernandez M.F.,CIBER ISCIII | Parera J.,CSIC - Institute of Environmental Assessment And Water Research | Arrebola J.P.,University of Granada | And 13 more authors.
Science of the Total Environment

Because fetuses are considered significantly more sensitive to various environment toxicants, there is a need for continuous biomonitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls PCBs (DL-PCBs) to assess their impact on this susceptible population. The aim of this study was to assess the concentration of PCDD/Fs and DL-PCBs in placenta samples from women participating in the Spanish Environment and Childhood (INMA) birth cohort study and to evaluate whether maternal and child characteristics predict placenta concentrations of these pollutants. The presence of PCDD/Fs and DL-PCBs was investigated in 50 placenta samples selected at random in the recruitment period 2000-2008. Multivariable regression models were constructed. Mothers had a mean age at delivery of 30.7years (18.0-38.0years), pre-pregnancy BMI of 23.3kg/m2 (18.0-40.2kg/m2), and 31% were smokers. Median total concentrations of PCDD/Fs and DL-PCBs were 6.9pgWHO-TEQ/g lipid and 2.1pgWHO-TEQ/g lipid, respectively. In comparison to the few previous studies in placenta, total TEQ levels were among the lowest recorded in comparable general populations. The congener distribution pattern and the frequencies and concentrations of PCDD/F and DL-PCB congeners were similar to previous reports in placenta. PCDD/F and DL-PCB exposure was related to the age of the mother and the year of the delivery. Although placental concentrations cannot be considered wholly appropriate predictors for evaluating fetal exposure to these contaminants, they can provide a good indication of both maternal and infant prenatal and postnatal exposure and can be used as a proxy for fetal exposure. © 2012 Elsevier B.V. Source

News Article
Site: http://phys.org/biology-news/

Through experiments meant to generally reflect runoff from a multiple-homeowner watershed, investigators found that pesticide mixtures had negative effects on the abundance of certain snails, water fleas, and crustaceans. "The effects we observed indicate that many species were affected at a sublethal level," said Dr. Simone Hasenbein, lead author of the Environmental Toxicology & Chemistry study. "Thus, populations exposed to low concentrations of pesticides could be even more sensitive to other abiotic or biotic factors such as invasive species, or changes in salinity or temperature leading to a magnification of multi-stressor situations." More information: Simone Hasenbein et al. A long-term assessment of pesticide mixture effects on aquatic invertebrate communities, Environmental Toxicology and Chemistry (2015). DOI: 10.1002/etc.3187

News Article | January 10, 2014
Site: venturevillage.eu

Global Founders Capital, the German VC launched by the Samwer brothers, and Redline Capital Management have announced a €6.1m investment in UK startup Iwoca. Existing investors Beyond Digital Media and Talis Capital also contributed to the round. Launched in March 2012, Iwoca provides short-term loans to UK-based eCommerce services. The startup plans to use the latest funding round to grow its UK operations and expand to Europe. This is the fifth investment Global Founders Capital has announced after launching early last year – the VC also holds shares in European startups Lingoda, Kreditech, Videdressing and Girl Meets Dress. Headed up by former Delivery Hero cofounder Fabian Siegel along with Rocket Internet founders Marc and Oliver Samwer, the €150m fund is stage-agnostic – able to invest anywhere between €100k and €10m. “We invest in proven concepts with huge market potential”, Siegel said on the Iwoca investment. “We will put our expertise in building internet companies and our global network at their disposal to help them drive growth.” Iwoca CEO Christoph Rieche added: ”Our highly innovative approach to data-analysis and credit scoring coupled with Oliver Samwer’s experience in franchise building puts us in an incredibly strong position to take advantage of the structural change within the business lending industry.” All images in this article are subject to the Creative-Commons-Lizenz (credit - no editing, CC BY-ND , link to the legally-binding license agreement). Excluded are pictures that are labelled differently, including from Panthermedia, Fotolia, Pixelio, Morguefile, along with press photos or publishers' own visual material.

News Article
Site: http://phys.org/biology-news/

The scientists observed several species in the contaminated water body, including the less standard species for these tests, such as mini-snails and copepods. Credit: Hasenbein Bodies of water are "sinks", and thereby bind contaminants particularly well. If even slightly toxic concentrations in water are to be detected, the growth and swimming behavior of small crustaceans, mini-snails and copepods should be used for ecotoxicological assessments. This was the conclusion of a scientist from the TUM, who carried out a number of studies on the subject in cooperation with the University of California in Davis. She also confirmed that it is more informative to test several substances in parallel on various aquatic species, rather than only carrying out individual toxicity tests. If a small crustacean does not grow properly, this can affect its reproduction. And if it is no longer able to move normally, it cannot flee from predators or from changing temperatures, which eventually has a fatal outcome. In scientific research, these effects are referred to as "sublethal effects". However, worldwide standard methods of pesticide analysis and the risk assessments associated with them only consider the lethal (deadly) effects. For the first time, three studies published in "Ecotoxicology", "Environmental Science and Pollution Research" and "Environmental Toxicology and Chemistry" demonstrate the sublethal effects on swimming behavior and growth, caused by widely used pesticides on the animals being studied. Moreover, the results indicate that the substances influence the underwater world for weeks, even if they are no longer detectable using standard methods. Pesticides become more toxic as a combined package Another factor is the mix of pesticides: "We looked at the insecticides not individually, but as a mixture, in order to investigate their interaction with one another", explains lead author Dr. Simone Hasenbein. "In addition, we observed several species in the contaminated water body, including the less standard species for these tests, such as mini-snails and copepods." The tests took place over a period of ten days in the laboratory and also for six months in the field. Eventually, significantly negative effects resulting from the combined pesticide pollution in the water were found for twelve of the 15 small invertebrates and ten of the 16 zooplankton species. "Another point that was considered was how long the insecticide remained detectable in water", was Dr. Hasenbein's explanation of the method - "thus, one of the three substances was still detectable after six weeks." - Firstly, the laboratory tests provided an indication of the concentrations at which the contaminants influence the growth and swimming behavior of the organisms. - The field studies proved the long-term effects on an entire ecosystem, its food web and its community structures. The negative effects on aquatic ecosystems could only be pinned down once all the results were combined. Since the microorganisms being studied can be influenced by the pesticides for much longer than these substances remain detectable, this also leads to the conclusion that bodies of water are far more polluted than all previous research had demonstrated. The changes in the animals which are detectable from their swimming behavior, growth or weight, and which eventually lead to their death (sublethal), are an important indicator of this. To date, however, there is no valid scale showing the point from which, for example, a delay in growth has a fatal outcome for the animal. Therefore, study author Dr. Hasenbein is advocating this approach in particular: "Sublethal endpoints need to be integrated into the methods used in ambient water monitoring, to allow long-term negative effects on aquatic ecosystems to be detectedreliably, even when the pesticide concentrations in the water are low", says the scientist. "A crustacean population which is exposed to low-level contaminant pollution could be more susceptible to invasive species, changes in water temperature or different salt concentrations, because the permanent, low-level pesticide contamination increases stress on the animals." This is an important aspect, especially in the light of climate change, and should therefore be taken into consideration in future ecotoxicologic assessments. More information: Hasenbein S, Lawler SP, Geist J, Connon RE.: A long-term assessment of pesticide mixture effects on aquatic invertebrate communities. Environmental Toxicology and Chemistry, 13.11.2015. DOI: 10.1002/etc.3187 Simone Hasenbein et al. A comparison of the sublethal and lethal toxicity of four pesticides in Hyalella azteca and Chironomus dilutus, Environmental Science and Pollution Research (2015). DOI: 10.1007/s11356-015-4374-1 Simone Hasenbein et al. The use of growth and behavioral endpoints to assess the effects of pesticide mixtures upon aquatic organisms, Ecotoxicology (2015). DOI: 10.1007/s10646-015-1420-1

Llorente M.T.,Environmental Toxicology | Parra J.M.,Environmental Toxicology | Sanchez-Fortun S.,Complutense University of Madrid | Castano A.,Environmental Toxicology
Water Research

The cytotoxicity and genotoxicity of 11 organic fractions from sewage treatment plant (STP) effluents were tested using the RTG-2 rainbow trout permanent cell line. An automated in vitro micronucleus assay developed for RTG-2 cells was used to test the genotoxicity, whereas neutral red uptake, kenacid blue protein assay and ATP content were used to evaluate cytotoxicity. The induction of micronuclei (MN) and alterations in the cell cycle were analysed in these cells by flow cytometry after exposure to the organic fractions for 72 h. More than half of the organic extracts tested demonstrated a significant increase in the MN frequency, thus indicating that most of them can be considered to be genotoxic. The extracts were analysed chemically by GC/MS. Although the most frequently detected compounds in the effluents were bisphenol A (BPA), octylphenol (OP), di-2-ethylhexyl phthalate (DEHP) and dibutyl phthalate (DBP), as well as other possible mutagens, the concentrations cannot explain the genotoxicity of the individual chemicals, thereby suggesting a mixture effect. The results obtained support the need to apply effect-based tests to monitor complex mixtures as the most accurate means of assessing the genotoxicity of environmental samples. © 2012 Elsevier Ltd. Source

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