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1.
Environmental Science and Pollution Research - With the increase in global population, industrialization, and urbanization, waste from construction, renovation, and demolition (CRD) activities has... 相似文献
2.
Carboxylic acids are ubiquitous and important components of the troposphere; they are currently measured in different environments. They are thought to have several sources comprising primary biogenic and anthropogenic emissions, hydrocarbons gas-phase oxidations, and some carbonyl compounds aqueous-phase oxidations. In the present review we make a synthesis of the concentrations of low molecular weight carboxylic acids in tropospheric aqueous and gaseous phases and in aerosol particles for different environments. We also successively examine the major sources of carboxylic acids and discuss their relative contribution to tropospheric concentrations for various environments as well as the principal sinks of these compounds. 相似文献
3.
The chloroform flux through the environment is apparently constant at some 660±220 Gg yr −1 (±1σ) and about 90% of the emissions are natural in origin: the largest single source being in offshore sea water (contributing 360±90 Gg yr −1), with soil processes the next most important (220±100 Gg yr −1). Other natural sources, mainly volcanic and geological, account for less than 20 Gg yr −1. The non-natural sources total 66±23 Gg yr −1 and are much better characterised than the natural sources. They are predominantly the result of using strong oxidising agent on organic material in the presence of chloride ion, a direct parallel with the natural processes occurring in soils. Chloroform partitions preferentially into the atmosphere; the equilibrium distribution is greater than 99% and the average global atmospheric concentration has been calculated to be 18.5 pmol mol−1. Atmospheric oxidation, the principal removal process, is approximately in balance with the identified source fluxes. Chloroform is widely dispersed in the aquatic environment (even naturally present in some mineral waters). Consequently, it is also widely dispersed in the tissue of living creatures and in foodstuffs but there is little evidence of bioaccumulation and the quantities in foodstuffs and drinking water are not problematical for human ingestion at the highest concentrations found. Definitive studies have shown that current environmental concentrations of chloroform do not present an ecotoxicological risk, even to fish at the embryonic and larval stages when they are most susceptible. By virtue of the very small amounts that actually become transported to the stratosphere, chloroform does not deplete ozone materially, nor is it a photochemically active volatile organic compound (VOC). It has a global warming potential that is less than that of the photochemically active VOCs and is not classed as a greenhouse gas. 相似文献
4.
Naphthenic acids occur naturally in crude oils and in oil sands bitumens. They are toxic components in refinery wastewaters and in oil sands extraction waters. In addition, there are many industrial uses for naphthenic acids, so there is a potential for their release to the environment from a variety of activities. Studies have shown that naphthenic acids are susceptible to biodegradation, which decreases their concentration and reduces toxicity. This is a complex group of carboxylic acids with the general formula CnH(2n+Z)O2, where n indicates the carbon number and Z specifies the hydrogen deficiency resulting from ring formation. Measuring the concentrations of naphthenic acids in environmental samples and determining the chemical composition of a naphthenic acids mixture are huge analytical challenges. However, new analytical methods are being applied to these problems and progress is being made to better understand this mixture of chemically similar compounds. This paper reviews a variety of analytical methods and their application to assessing biodegradation of naphthenic acids. 相似文献
5.
Pharmaceuticals and other anthropogenic trace contaminants reach wastewaters and are often not satisfactorily eliminated in sewage treatment plants. These contaminants and/or their degradation products may reach surface waters, thus influencing aquatic life. In this study, the behavior of five different antihypertonic pharmaceuticals from the sartan group (candesartan, eprosartan, irbesartan, olmesartan and valsartan) is investigated in lab-scale sewage plants. The elimination of the substances with related structures varied broadly from 17 % for olmesartan up to 96 % for valsartan. Monitoring data for these drugs in wastewater effluents of six different sewage treatment plants (STPs) in Bavaria, and at eight rivers, showed median concentrations for, e.g. valsartan of 1.1 and 0.13 μg L ?1, respectively. Predicted environmental concentrations (PEC) were calculated and are mostly consistent with the measured environmental concentrations (MEC). The selected sartans and the mixture of the five sartans showed no ecotoxic effects on aquatic organisms in relevant concentrations. Nevertheless, the occurrence of pharmaceuticals in the environment should be reduced to minimize the risk of their distribution in surface waters, ground waters and bank filtrates used for drinking water. 相似文献
6.
Environmental Science and Pollution Research - The ban and restriction of polychlorinated biphenyls (PCBs) and major brominated flame retardants (BFRs), including hexabromocyclododecane (HBCD) and... 相似文献
7.
Veterinary antibiotics (VAs) are widely used in many countries worldwide to treat disease and protect the health of animals. They are also incorporated into animal feed to improve growth rate and feed efficiency. As antibiotics are poorly adsorbed in the gut of the animals, the majority is excreted unchanged in faeces and urine. Given that land application of animal waste as a supplement to fertilizer is often a common practice in many countries, there is a growing international concern about the potential impact of antibiotic residues on the environment. Frequent use of antibiotics has also raised concerns about increased antibiotic resistance of microorganisms. We have attempted in this paper to summarize the latest information available in the literature on the use, sales, exposure pathways, environmental occurrence, fate and effects of veterinary antibiotics in animal agriculture. The review has focused on four important groups of antibiotics (tylosin, tetracycline, sulfonamides and, to a lesser extent, bacitracin) giving a background on their chemical nature, fate processes, occurrence, and effects on plants, soil organisms and bacterial community. Recognising the importance and the growing debate, the issue of antibiotic resistance due to the frequent use of antibiotics in food-producing animals is also briefly covered. The final section highlights some unresolved questions and presents a way forward on issues requiring urgent attention. 相似文献
8.
本文介绍了蟹岛生态园区农业废气物及生活污水的资源化处理工艺方案 ,通过对沼气池和生活污水厌氧 -好氧 -生态塘处理系统进行综合设计 ,实现了节能环保和废弃物无害化综合处理利用。形成了种植业、养殖业、肥料加工、能源利用和休闲度假有机结合的生态农业经济 ,为实现农村经济可持续发展提供了一种新模式 相似文献
9.
This article includes a survey of chromium (Cr) occurrence in different environmental compartments, its pathways in the environment and the cross-sectional presentation of Cr speciation methods against the background of Cr chemistry. The aim of the article is to demonstrate that knowledge of interconversion processes between different Cr forms is necessary to understand its behaviour and role in the environment, in addition to enabling reliable Cr speciation analysis to be performed. The current methods of Cr speciation are presented, characterized and their usefulness discussed. These must rely on superior separation and detection capabilities since Cr in environmental compartments is mostly at trace or ultra-trace level. The need for using unique techniques of sampling, storage, handling and separation for Cr speciation is documented. 相似文献
10.
Plastic waste is a source of organic contaminants such as hexabromocyclododecanes (HBCDs). HBCDs have been found to cause developmental and reproductive toxicity; it is important to investigate the occurrence and metabolization of HBCDs in the soil environments with plastic waste contamination. This work analyzed HBCDs and their metabolites in soil and plant samples collected from Xinle and Dingzhou—the major plastic waste recycling centers in North China. Results showed that total HBCD concentrations in soils followed the order: plastic waste treatment site (11.0–624 ng/g) > roadside (2.96–85.4 ng/g) ≥ farmland (8.69–55.5 ng/g). HBCDs were detected in all the plant samples with total concentrations ranging from 3.47 to 23.4 ng/g. γ-HBCD was the dominant congener in soils, while α-HBCD was preferentially accumulated in plants. Compositions of HBCD isomers in soils and plants were significantly different ( P < 0.05) among sampling sites and among plant species. HBCDs in farmland soil and all plant samples exhibited high enantio-selectivity based on the enantiomeric fractions (EFs). Furthermore, metabolites of pentabromocyclododecenes (PBCDEs) were frequently identified in soils, and mono-OH-HBCDs were the most common ones in plants. This study for the first time provides evidences of HBCD contamination in the soil-plant system caused by plastic waste, their stereo-selectivity, and metabolization behavior, improving our understanding of the environmental behavior and fate of HBCDs. 相似文献
11.
Environmental Science and Pollution Research - With the rapid socio-economic and industrial development, the problem of water shortage is becoming increasingly serious. Seeking alternative water... 相似文献
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Environmental Science and Pollution Research - An increase in population compels the textile industry to expand production to fulfill the apparel requirement, resulting in huge textile waste. These... 相似文献
13.
为对垃圾填埋场封场后如何进行生态恢复研究提供基础资料,对超负荷运转中的广州市李坑生活垃圾填埋场周围的植被现状进行了调查,测算了物种量、覆盖度、污染状况等。同时运用植被覆盖度、结构、物种量和相对物种量等级评价以及对Zn、Cd等6种污染物的质量指数进行了评价。结果表明,所调查填埋场场区及灌区内有轻度污染,而场外与灌区外则相对较轻或无污染。 相似文献
14.
The fate and behavior of cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in the environment were reviewed. We evaluated their usage data and patterns, physico-chemical properties, toxicology, partitioning and degradation, methods of detection, and concentrations. The use of cVMS as an intermediate in the formation of silicone polymers, personal care and household products has resulted in their widespread environmental exposure; they have been detected in biogas, air, water, soil, biosolid, sediment, and biota samples. Modeled and experimental results suggest that cVMS may be subject to long-range atmospheric transport, but have low potential to contaminate the Arctic. For D4 and D5, there was no evidence of trophic biomagnification in aquatic food webs, while some aquatic organisms demonstrated a high degree of bioconcentration and bioaccumulation. High concentrations of cVMS observed in indoor air and biosolids resulted from point sources. Concentrations of cVMS in water, sediment, and soil were all below their no-observed-effect-concentrations. 相似文献
15.
研究了某电子垃圾拆解园周边151个农田土壤样品中16种多环芳烃(PAHs)的污染特征和环境风险。结果表明,125个表层土壤样品中PAHs总质量浓度在149.0~2.0×104μg/kg,均值为1 805.5μg/kg,随着剖面土壤深度增加,PAHs含量总体呈递减趋势。通过来源解析,电子拆解园周围土壤中PAHs污染主要由废弃的电子电器元件的粗放燃烧和汽车尾气排放共同引起。土壤风险评估表明,7种类二噁英毒性PAHs的毒性当量(TEQPAH)在6.000×10-5~0.689pg TEQ/g,平均值为0.015pg TEQ/g;苯并(a)芘、二苯并(a,h)蒽、苯并(a)蒽、苯并(b)荧蒽、茚并(1,2,3-cd)芘致癌风险率超出百万分之一的样本比例分别为20.53%、6.62%、1.99%、2.65%、2.65%,其中采样点1、68两个点位表层土壤的苯并(b)荧蒽致癌风险率超过了万分之一。 相似文献
16.
The sampling procedure of solid and gaseous pollutants, contained in flue gas emitted into the atmosphere by solid waste incinerating furnaces were investigated. Because of their extraordinary toxicological properties, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are taken into particular consideration. The analytical work is based on the use of high-resolution gas chromatography in combination with low-resolution mass spectrometry. Details of the extensive sample clean-up will follow the GC-MS separation and identification of the isomers detected for each group of PCDDs and PCDFs. Quantitative data of these pollutants distribution levels deriving from different investigated incinerators are also reported. 相似文献
17.
由抗生素类物质的使用引发的土壤环境污染问题已引起全球的广泛关注.中国是抗生素类物质的消费大国,其抗生素污染问题亟待解决.介绍了世界范围内使用最为广泛的四环紊类抗生索在土壤环境中的污染现状;分析了国内外有关四环素类抗生索的研究状况和进展;揭示了生物有效性研究在评价四环素类抗生索对土壤环境生态风险的重要意义;最后对四环素类... 相似文献
18.
近年来,国内外开始关注药品与个人护理品(PPCPs)对环境的污染.三氯生(TCS)作为药品与个人护理品的杀菌、防腐剂在环境中普遍存在.详细介绍了三氯生的基本性质及其在水环境中的赋存现状,并初步比较了污水处理工艺对三氯生的去除效果. 相似文献
19.
为实现城市生活垃圾减量化、无害化和资源化,采用热重分析天平和实验室固定床热解反应器进行城市生活垃圾(MSW)与园林废弃物共热解实验,研究了不同热解终温、松树枝和柳树枝添加比例对热解产物产率影响,并利用气质联用色谱分析仪(GC-MS)对热解油进行表征分析。实验结果表明:MSW、松树枝和柳树枝的热解过程均可以分为3个阶段,主要包括脱水、热解、炭化;MSW、松树枝和柳树枝单独热解时最大失重速率分别出现在321.48、358.23和377.83℃;MSW与松树枝共热解DTG曲线在热解反应第2阶段有2个析出峰,分别在342.32℃和471.48℃,比MSW单独热解时,失重率增加了7.29%。当城市生活垃圾与松树枝、柳树枝的添加量分别为3:1时,热解液体产物产率明显升高,热解油中醇类、羧酸类、醛类等含氧有机物的含量降低,热值增加,热解油中氧含量降低,且松树枝对共热解焦油的脱氧效果更为显著,热解油品质得到提升。 相似文献
20.
鉴于四川省重要的生态屏障功能和多样的地形气候条件,随机选择该地区10个自然村,通过问卷调查、采样测试等方法,对农村固体废物的处理现状、特性与农民环保意识进行调研,以期为农村典型污染物的管理与处理提供一定的理论支撑和技术指导。调研表明:四川省农村生活垃圾统一清运率相对较高,生活垃圾与塑料薄膜以焚烧为主;人畜粪便主要用作肥料,作物秸秆主要用于生活燃料,绝大部分灰渣均还田,大部分生活污水直接排放,这些处理方式导致了地表水、固体废物和大气的复合型污染。调查村生活垃圾产生量平均值为227g/(人·d),主要组分包括厨余、灰土、纸类、橡胶,生活垃圾平均容重、含水率、灰分、可燃物、低位热值分别为129kg/m3、43.42%、28.22%、28.36%和6 048kJ/kg。农村群众对生活垃圾特性的认知不高,参与环境管理的意愿和对典型污染物处理的支付意愿相对较弱;四川省农村生活垃圾和生活污水处理宜充分利用户用沼气池和中小型沼气工程,采取分散和自行处理为主、集中处理为辅的模式。 相似文献
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