31,024 research outputs found
Comparative ecotoxicity of three polluted industrial soils for the Collembola Folsomia candida
We tried to quantify the ecotoxicity of three industrial soil samples contaminated by different metals, using the Collembolan Folsomia candida as a biological model and mortality, growth and reproduction as parameters. The observed ecotoxicities are rather normal for the first such soil sample (aluminum factory) but are high for the second sample (ore treatment) and relatively low for the third one (zinc factory) considering its high metal concentrations. For these last two soil samples, an unusual ecotoxicity plotting is observed: two high ecotoxicity recordings fit with a low and high percentage of polluted soil to non-polluted soil and noticeably lower ecotoxicity recordings are observed between them. Chemical analyses of metals in pore waters show that arsenic probably explains part of such an unusual ecotoxicity curve. Otherwise, mortality and growth of the animals are less sensitive parameters than reproduction. Our experiments show that the results of the ecotoxicological assays of polluted soils are complex and difficult to interpre
Edito of the special focus issue on Environmental Toxicity of Nanoparticles
“The main goal of this special focus issue is to introduce the main parameters that affect the potential ecotoxicity of nanoparticles and to describe the state of the art
with a few selected examples of interaction of different nanoparticles...
Life cycle assessment of completely recyclable concrete
Since the construction sector uses 50% of the Earth. s raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete
EURO-ECOLE: Assessment of the Bioavailability and Potential Ecological Effects of Copper in European Surface Waters ; subproject 4: Evaluation and improvement of the ecological relevance of laboratory generated toxicity data
This report summarizes the acute and chronic toxicity of copper to algae, Daphnia and a few other freshwater species in standard laboratory test water and a wide range of natural surface waters (collected across Europe), with a wide range of pH, dissolved organic carbon (DOC) concentration and hardness. These data can be used for validation of bioavailability models such as the biotic ligand model (BLM)
Bioassays with terrestrial and aquatic species as monitoring tools of hydrocarbon degradation
In this study chemical analyses and ecotoxicity tests were applied for the assessment of a heavily hydrocarbon-contaminated soil prior and after the application of a remediation procedure that consisted in the stimulation of soil autochthonous populations of hydrocarbon degraders in static-ventilated biopiles. Terrestrial bioassays were applied in mixtures of test soils and artificial control soil and studied the survival and reproduction of Eisenia fetida and the avoidance response of E. fetida and Folsomia candida. Effects on aquatic organisms were studied by means of acute tests with Vibrio fischeri, Raphidocelis subcapitata, and Daphnia magna performed on aqueous elutriates from test soils. The bioremediation procedure led to a significant reduction in the concentration of hydrocarbons (from 34264 to 3074 mg kg-1, i.e., 91 % decrease) and toxicity although bioassays were not able to report a percentage decrease of toxicity as high as the percentage reduction. Sublethal tests proved the most sensitive terrestrial bioassays and avoidance tests with earthworms and springtails showed potential as monitoring tools of hydrocarbon remediation due to their high sensitivity and short duration. The concentrations of hydrocarbons in water extracts from test soils were 130 and 100 µg L-1 before and after remediation, respectively. Similarly to terrestrial tests, most aquatic bioassays detected a significant reduction in toxicity, which was almost negligible at the end of the treatment. D. magna survival was the most affected by soil elutriates although toxicity to the crustacean was associated to the salinity of the samples rather than to the concentration of hydrocarbons. Ecotoxicity tests with aqueous soil elutriates proved less relevant in the assessment of hydrocarbon-contaminated soils due to the low hydrosolubility of hydrocarbons and the influence of the physicochemical parameters of the aquatic mediumPostprint (author's final draft
The recycling of OMC's carbon reinforcement by solvolysing thermoset matrix. A way of sustainability for composites.
Originally developed for high-tech applications, carbon fibre/thermoset matrix composites have been increasingly used in leisure and sports industries, for several years. But the carbon reinforcement is the most expensive constituent, and also the most environmentally impacting in the elaboration of a composite part. To this day, no end-of-life solution or recycling process efficiently exists. This paper aims at demonstrating that recovering the carbon reinforcement is possible, technically and economically speaking. Moreover, it is particularly the basis for a life cycle analysis that assesses benefits and environmental challenges of this recycling loop based on the reinforcement recovery by a solvolysis of the organic matrix. Lastly, the lack of data to consider the better end-of-life option (reuse, recycling, energy recovery and material valorisation) will be underlined
Aggregation and ecotoxicity of CeO2 nanoparticles in synthetic and natural waters with variable pH, natural organic matter concentration and ionic strength
Transportation Life Cycle Assessment Synthesis: Life Cycle Assessment Learning Module Series
The Life Cycle Assessment Learning Module Series is a set of narrated, self-advancing slideshows on various topics related to environmental life cycle assessment (LCA). This research project produced the first 27 of such modules, which are freely available for download on the CESTiCC website http://cem.uaf.edu/cesticc/publications/lca.aspx. Each module is roughly 15- 20 minutes in length and is intended for various uses such as course components, as the main lecture material in a dedicated LCA course, or for independent learning in support of research projects. The series is organized into four overall topical areas, each of which contain a group of overview modules and a group of detailed modules. The A and α groups cover the international standards that define LCA. The B and β groups focus on environmental impact categories. The G and γ groups identify software tools for LCA and provide some tutorials for their use. The T and τ groups introduce topics of interest in the field of transportation LCA. This includes overviews of how LCA is frequently applied in that sector, literature reviews, specific considerations, and software tutorials. Future modules in this category will feature methodological developments and case studies specific to the transportation sector
The initial tolerance to sub-lethal Cd exposure is the same among ten naïve pond populations of Daphnia magna, but their micro-evolutionary potential to develop resistance is very different
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