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281.
Engineered nanomaterials (ENM) are expected to hold considerable potential for products that offer improved or novel functionalities. For example, nanotechnologies could open the way for the use of textile products outside their traditional fields of applications, for example, in the construction, medical, automobile, environmental and safety technology sectors. Consequently, nanotextiles could become ubiquitous in industrial and consumer products in future. Another ubiquitous field of application for ENM is fa?ade coatings. The environment and human health could be affected by unintended release of ENM from these products. The product life cycle and the product design determine the various environmental and health exposure situations. For example, ENM unintentionally released from geotextiles will probably end up in soils, whereas ENM unintentionally released from T-shirts may come into direct contact with humans and end up in wastewater. In this paper we have assessed the state of the art of ENM effects on the environment and human health on the basis of selected environmental and nanotoxicological studies and on our own environmental exposure modeling studies. Here, we focused on ENM that are already applied or may be applied in future to textile products and fa?ade coatings. These ENM's are mainly nanosilver (nano-Ag), nano titanium dioxide (nano-TiO(2)), nano silica (nano-SiO(2)), nano zinc oxide (nano-ZnO), nano alumina (nano-Al(2)O(3)), layered silica (e.g. montmorillonite, Al(2)[(OH)(2)/Si(4)O(10)]nH(2)O), carbon black, and carbon nanotubes (CNT). Knowing full well that innovators have to take decisions today, we have presented some criteria that should be useful in systematically analyzing and interpreting the state of the art on the effects of ENM. For the environment we established the following criteria: (1) the indication for hazardous effects, (2) dissolution in water increases/decreases toxic effects, (3) tendency for agglomeration or sedimentation, (4) fate during waste water treatment, and (5) stability during incineration. For human health the following criteria were defined: (1) acute toxicity, (2) chronic toxicity, (3) impairment of DNA, (4) crossing and damaging of tissue barriers, (5) brain damage and translocation and effects of ENM in the (6) skin, (7) gastrointestinal or (8) respiratory tract. Interestingly, some ENM might affect the environment less severely than they might affect human health, whereas the case for others is vice versa. This is especially true for CNT. The assessment of the environmental risks is highly dependent on the respective product life cycles and on the amounts of ENM produced globally.  相似文献   
282.
Agricultural land use has shifted towards more intensified production because the prices of agricultural products have increased during the past years. Just a few years ago, voluntary area set-aside was a lucrative alternative in some regions. But nowadays, land is re-cultivated again, inter alia with biomass crops. Consequently, this affects the soil and nutrient balances in agriculture. The global changes on the world markets influence agricultural production and thus the water cycle at the regional scale. In this paper, the regional developments and policy alternatives are discussed for the Elbe River Basin. The paper concludes that on average, no substantial effects of nitrogen surpluses are expected for the Elbe River Basin due to a continuing decline in animal herds. However, at the county level, nitrogen surpluses are likely to exceed the maximum threshold of 60 kg nitrogen per hectare (stipulated in the German Fertiliser Regulation) due to regional concentrations of animal production. A halving of the threshold to 30 kg per hectare shows that the marginal costs of nitrogen surplus reduction regionally exceeded 10 Euros per kilogram nitrogen.  相似文献   
283.
Biochar derived from pyrolysis has received much attention recently as a soil additive to sequester carbon and increase soil fertility. Hydrochar, a brown, coal-like substance produced via hydrothermal carbonization, has also been suggested as a beneficial soil additive. However, before soil application, both types of char need to be tested for potential toxic effects. The aim of this study was to develop simple, inexpensive, and easy-to-apply test procedures to identify negative effects of chars but not to provide false-negative results. The following tests, based partly on ISO norm biotoxicity test procedures, were chosen: (i) cress germination test for gaseous phytotoxic emissions; (ii) barley germination and growth test; (iii) salad germination test; and (iv) earthworm avoidance test for toxic substances. Test reproducibility was ensured by carrying out each test procedure three times with the same biochar. Several modifications were necessary to adapt the tests for biochars/hydrochars. The tested biochar did not induce negative effects in any of the tests. In contrast, the beet-root chip hydrochar showed negative effects in all tests. In an extension to the regular procedure, a regrowth of the harvested barley shoots without further nutrient additions yielded positive results for the hydrochar, which initially had negative effects. This implies that the harmful substance(s) must have been degraded or they were water soluble and leached. Tests with a biochar and hydrochar showed that the proposed modified quick-check test procedures provide a fast assessment of risks and effects of char application to soils within a short period of time (<2 wk).  相似文献   
284.
Mining, smelting, land applications of sewage sludge, the use of fungicides containing copper (Cu), and other human activities have led to widespread soil enrichment and contamination with Cu and potentially toxic conditions. Biochar (BC) can adsorb several substances, ranging from herbicides to plant-inhibiting allelochemicals. However, the range of potential beneficial effects on early-stage plant growth with regard to heavy metal toxicity is largely unexplored. We investigated the ameliorating properties of a forestry-residue BC under Cu toxicity conditions on early plant growth. Young quinoa plants () were grown in the greenhouse in the presence of 0, 2, and 4% BC application (w/w) added to a sandy soil with 0, 50, or 200 μg g Cu supplied. The plants without BC showed severe stress symptoms and reduced growth shortly after Cu application of 50 μg g and died at 200 μg Cu g. Increasing BC concentrations in the growth medium significantly increased the plant performance without Cu toxicity or under Cu stress. At the 4% BC application rate, the plants with 200 μg g Cu almost reached the same biomass as in the control treatment. In the presence of BC, less Cu entered the plant tissues, which had reduced Cu concentrations in the order roots, shoots, leaves. The amelioration effect also was reflected in the plant-soil system CO gas exchange, which showed clear signs of improvement with BC presence. The most likely ameliorating mechanisms were adsorption of Cu to negatively charged BC surfaces and an improvement of the water supply. Overall, BC seems to be a beneficial amendment with the potential to ameliorate Cu toxicity in sandy soils. Further research with a broad spectrum of different soil types, BCs, and crop plants is required.  相似文献   
285.
The innovative approach to the protection and management of water resources at the basin scale introduced by the European Union water framework directive (WFD) requires new scientific tools. WFD implementation also requires the participation of many stakeholders (administrators, farmers and citizens) with the aim of improving the quality of river waters and basin ecosystems through cooperative planning. This approach encompasses different issues, such as agro-ecology, land use planning and water management. This paper presents the results of a methodology suggested for implementing the WFD in the case of the Seveso river contract in Italy, one of the recent WFD applications. The Seveso basin in the Lombardy region has been one of the most rapidly urbanizing areas in Italy over the last 50?years. First, land use changes in the last 50?years are assessed with the use of historical aerial photos. Then, elements of an ecological network along the river corridor are outlined, and different scenarios for enhancing existing ecological connections are assessed using indicators from graph theory. These scenarios were discussed in technical workshops with involved stakeholders of the river contract. The results show a damaged rural landscape, where urbanization processes have decimated the system of linear green features (hedges/rows). Progressive reconnections of some of the identified network nodes may significantly increase the connectivity and circuitry of the study area.  相似文献   
286.
Evaluation of the presence of drugs of abuse in tap waters   总被引:1,自引:0,他引:1  
A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L−1, in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L−1. Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L−1). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L−1 (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L−1, respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L−1). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L−1 (Spain) and 0.3 ng L−1 (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.  相似文献   
287.
Characterization of bacterial communities at heavy-metal-contaminated sites   总被引:2,自引:0,他引:2  
The microbial community in soil samples from two long-term contaminated sites was characterized by using culture-dependent and culture-independent methods. The two sites investigated contained high amounts of heavy metals and were located in the upper Silesia Industrial Region in southern Poland. The evaluation of the aerobic soil microbial population clearly demonstrated the presence of considerable numbers of viable, culturable bacteria at both sites. A high fraction of the bacterial population was able to grow in the presence of high amounts of metals, i.e. up to 10 mM Zn2+, 3 mM Pb2+ or 1 mM Cu2+. Site 1 contained significantly (P < 0.05) lower bacterial numbers growing in the presence of 10 mM Zn2+ than site 2, while the opposite was observed for bacteria tolerating 1 mM Cu2+. This coincided with the contents of these two metals at the two sites. Ecophysiological (EP) indices for copiotrophs (r-strategists) and oligotrophs (K-strategists) pointed to high bacterial diversity at both sites. Fluorescence in situ hybridization (FISH) analysis indicated that Actinobacteria and Proteobacteria represent the physiologically active fraction of bacteria at the two sites. Shannon diversity (H′) indices for FISH-detected bacterial phylogenetic groups were not significantly different at the two sites.  相似文献   
288.
289.

Introduction  

Many previous studies revealed a high ability of mushrooms to accumulate heavy metals from environment. This paper concerns the capacity of some wild macromycetes belonging to Russula genus to accumulate heavy metals in natural condition of pH (between 6.5 and 6.8) and the pattern of metal translocation in the fruiting body.  相似文献   
290.

Background and scope  

Effect-directed analysis is increasingly used for the identification of key toxicants in environmental samples and there is a growing need for in vivo biotests as diagnostic tools. Within this study, we performed an in vivo sediment contact test, applicable on both native field samples and their extracts or fractions, in order to be able to compare the results from both field and laboratory studies.  相似文献   
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