Impact of peri-urban landscape on the organic and mineral contamination of pond waters and related risk assessment

Environmental Science and Pollution Research - Ponds are important for their ecological value and for the ecosystem services they provide to human societies, but they are strongly affected by human...     

2种改进型SBR工艺的特点及浅析

介绍了CSBR及MSBR2种改进型SBR处理工艺，并比较分析了两者的优缺点。结果表明，尽管两者在除磷脱氮、工艺灵活性和占地等方面都有明显的优势，但两者有各自的优缺点，设计时应根据不同的边界条件择优选用。     

2种改进型SBR工艺的特点及浅析

介绍了CSBR及MSBR2种改进型SBR处理工艺,并比较分析了两者的优缺点。结果表明,尽管两者在除磷脱氮、工艺灵活性和占地等方面都有明显的优势,但两者有各自的优缺点,设计时应根据不同的边界条件择优选用。     

The Significance of Particulate Emissions

Fine participates are the subject of increasing concern as one of the major air pollutants. They contribute to smog formation. They are a health hazard because they bypass the respiratory filters and penetrate deep into the lungs, and because they may act synergistically with other pollutants. The sources of submicron particle size pollutants are discussed.     

Governmental Provisions to Manage and Eradicate Feral Swine in Areas of the United States

Feral swine (wild hogs) are one of the most widely distributed free-ranging mammals in the world. In the United States, feral swine serve as game animals for the sport of hunting in some areas, while they are nuisance species at other locations. Increasing feral swine populations creates negative impacts to growing crops, native plant communities, and wildlife. Feral swine can also serve as reservoirs for a number of bacterial and viral diseases that can infect wild animals, livestock, and humans. The US state governments are adopting statutes and regulations to reduce the growth and dispersal of feral swine populations. An analysis of these provisions suggests that while they seek to control feral swine populations, they are unlikely to provide any significant relief from damages to crops and native ecosystems. More localized reduction plans and a national disease control program are suggested to assuage damages being wrought by these invasive animals.     

An overview of uncertainties in modelling groundwater solute transport

Model predictions are uncertain because of uncertainties on future and/or anthropogenic stresses, parameter values and conceptual models. The first two groups of problems can be addressed through rather systematic methods (scenario analysis, error transmission techniques, automatic calibration algorithms, etc.). However, conceptual uncertainties are rarely given adequate attention. The objective of this paper is to synthesize conceptual difficulties associated with transport. These include: (1) processes that are significant at small scales may not be relevant at large scales; (2) inversely, new processes (e.g., dispersion) emerge in response to increase in scale and the way to represent them may depend on the assumed model structure; (3) the observed shapes of both breakthrough curves and pollutant plumes are not well represented by the classical transport equation; (4) porosities and dispersivities derived from field tracer tests often exhibit a directional dependence; etc. Though not directly related to solute transport, scale effects on hydraulic conductivity may also affect solute transport modelling. When these anomalies are examined, it is concluded that they are directly or indirectly caused by heterogeneity. Current approaches for dealing with heterogeneity can be divided into stochastic and deterministic. Stochastic methods have been successful in explaining qualitatively some anomalies of solute transport, but they appear to be far from reaching a stage at which they can be used routinely for solving realistic field problems. On the other hand, when applied with care, deterministic methods have been successfully used in actual problems. Yet, it can be argued that they fail to account for small-scale variability of concentrations so that they would become ineffective when dealing with nonlinear processes, such as chemical reactions. Relevance of on-going research for overcoming these difficulties is discussed.     

Abiotic degradation of chlorinated ethanes and ethenes in water

INTRODUCTION: Chlorinated ethanes and ethenes are among the most frequently detected organic pollutants of water. Their physicochemical properties are such that they can contaminate aquifers for decades. In favourable conditions, they can undergo degradation. In anaerobic conditions, chlorinated solvents can undergo reductive dechlorination. DEGRADATION PATHWAYS: Abiotic dechlorination is usually slower than microbial but abiotic dechlorination is usually complete. In favourable conditions, abiotic reactions bring significant contribution to natural attenuation processes. Abiotic agents that may enhance the reductive dechlorination of chlorinated ethanes and ethenes are zero-valent metals, sulphide minerals or green rusts. OXIDATION: At some sites, permanganate and Fenton's reagent can be used as remediation tool for oxidation of chlorinated ethanes and ethenes. SUMMARY: Nanoscale iron or bimetallic particles, due to high efficiency in degradation of chlorinated ethanes and ethenes, have gained much interest. They allow for rapid degradation of chlorinated ethanes and ethenes in water phase, but they also give benefit of treating dense non-aqueous phase liquid.     

Testing the extraction of 12 mycotoxins from aqueous solutions by insoluble beta-cyclodextrin bead polymer

Environmental Science and Pollution Research - Mycotoxins are toxic metabolites of filamentous fungi; they are common contaminants in numerous foods and beverages. Cyclodextrins are ring-shaped...     

Closing Comments

Fine particles are those which penetrate into the respiratory system where they may act as a carcinogen, may contribute to blockage of the alveoli, or may accommodate pulmonary pathogens . Mr. Harrington observed that fine particles are not a single pollutant but a large category of pollutants. It is therefore difficult to agree on a general definition of fine particles as a pollutant. However, it has been shown that particles with diameters smaller than 5 µm do penetrate past the nasal cavity and nasopharynx into the lungs and that particles with diameters as small as 0.01 µm are deposited in the lungs. Other problems associated with submicron particles are that they are slow in settling out of the atmosphere and they create haze and adverse weather modification.     

Identification of substances with potential for long-range transport as possible substances of very high concern

According to the European legislation, REACH, organic compounds are considered as substances of very high concern (SVHC) if they are persistent, bioaccumulative and toxic (PBT). A substance's long-range transport potential (LRTP) may also pose a risk to remote regions. This is, however, not yet explicitly included. For identification of compounds, which are not PBT according to REACH criteria, but show LRTP, we investigated 22,438 compounds from the Canadian Domestic Substance List (CDSL). The CDSL was searched for organic, neutral compounds. Substance properties were estimated with EPI Suite v4.00. Next, the substance list was edited in two ways: (1) The half-life criterion in air for LRTP as defined in the Stockholm Convention was applied. (2) For all compounds, indicators for persistence and LRTP were calculated with the multimedia model ELPOS v2.2. Applying the half-life criterion, we identified 594 substances, which are prone to LRT but are not PBT (non-PBT-L substances). In contrast, investigations with ELPOS lead to a shorter list of 188 substances, which are non-PBT-L substances. Finally, the list was compared with potential Arctic contaminants identified in previous literature. Our results show that there is a large number of organic chemicals which would not be considered as SVHC since they are not, at the same time, persistent, bioaccumulative and toxic according to REACH criteria. Nevertheless, they show LRTP according to different screening approaches and thus a potential hazard to remote regions.     

Soil and Compost Filters of Malodorant Gases

Removing low concentrations of pollutant gases from air streams is difficult and expensive.^1,2 Removal techniques include water scrubbing (with and without permanganate, hypochlorite, or lime), burning, and sorption by activated charcoal. The shortcomings of these techniques are that they require fuel, maintenance, water, high capital costs, they pollute the wash water, and/or some concentrate only, rather than remove the offender.     

Macrobenthic invertebrates as bioindicators of trace elements in high-mountain lakes

Environmental Science and Pollution Research - Alpine lakes are extreme ecosystems located in remote areas and populated by few but well-adapted species. Because of their remote location, they are...     

Efficacy of ginsenoside Rg3 nanoparticles against Ehrlich solid tumor growth in mice

Environmental Science and Pollution Research - Solid tumors are fairly common and face many clinical difficulties since they are hardly surgically resectable and broadly do not respond to radiation...     

Preliminary assessment of antimicrobial activity and acute toxicity of norfloxacin chlorination by-product mixture

Environmental Science and Pollution Research - Among drugs and personal care products, antibiotics arouse interest since they are widely used in human and veterinary medicine and can lead to the...     

Metallothionein expression in Aspergillus exposed to environmentally relevant concentrations of heavy metals at different pH levels

Environmental Science and Pollution Research - Heavy metal pollution represents a health threat. Many fungal species are capable of tolerating various heavy metals, especially if they are isolated...     

Desorption of CO2, SO2, and NH3 in the vacuum evaporation of desulfurization wastewater

Environmental Science and Pollution Research - Mechanical vapor compression and multi-effect evaporation have been widely used in achieving zero discharge of desulfurization wastewater as they are...     

Assessing the Impacts of Establishing MPAs on Fishermen and Fish Merchants: The Case of Lyme Bay,UK

Shortly after the implementation of a marine protected area (MPA) in Lyme Bay in 2008, inside which scallop dredging and bottom trawling is prohibited, a socio-economic impact assessment was initiated. This article presents the initial findings from this study. The aim was to understand the costs and benefits to fishermen and fish merchants of establishing the MPA. These were assessed using a combination of primary and secondary data. The results indicate that the impacts of the closure differ according to the gear type and the fishing location used by the fishermen. Static gear fishermen who fish inside the closed area have seen changes in terms of increased fishing effort, mostly because they have been able to increase the number of crab and whelk pots they deploy. The effects of the closure on static gear fishermen who fish outside the closed area has been reported in terms of increased conflicts with towed gear fishermen who now fish regularly in their traditional grounds. Fishermen using towed gear on the other hand have been impacted through displacement effects as they have been forced to look for other fishing grounds outside the closed area. Most fish merchants and processors initially claimed that they were heavily impacted by the closure but when they were interviewed 1 year after the closure they suggested a more stable picture. Preliminary analyses of landings data indicate that the introduction of the MPA has so far had minimal impacts on the average incomes and financial profits of fishermen and fish merchants. This conclusion, however, reflects a short-term view as the impacts of the closure of Lyme Bay are likely to be felt for a long time to come.     

The chemistry of carbonyl compounds in the atmosphere—A review

Carbonyl compounds are very important for the trophospheric physico-chemistry because they are the result of the first photo-oxidation stage of almost all organic compounds and they are the essential originators of the free radicals. In the present review we make a synthesis of the studies on the carbonyl compounds chemistry in the trophosphere by successively examining: measurement methods in the trophosphere, sources of primary carbonyl compounds, formation of secondary carbonyl compounds in the atmosphere, reactivity of carbonyl compounds in the atmosphere.     

Assessment of degradation of 18 antibiotics in the Closed Bottle Test

Large quantities of antibiotics are used in health care. After administration, they are discharged into the effluent and reach sewage treatment plants (STPs); if they are not degraded, they will eventually enter the environment. Antibiotics can affect bacteria in the environment and thus disturb natural elemental cycles. For this reason, it is necessary to take a closer look at the fate and effects of these substances in the environment. The biodegradability of 18 clinically important antibiotics and their effects on environmental bacteria was studied using the Closed Bottle Test (CBT) (OECD 301 D 1992). In addition, a toxicity control was performed in the CBT and the colony forming units (CFUs) were monitored. Disappearance of some of the 18 antibiotics was monitored by HPLC (high performance liquid chromatography) analysis. The antibiotics were used in two concentrations: (a) according to OECD 301 D in the mg/l-range and (b) on the basis of calculated concentrations in the influent of STPs in the microg/l-range. None of the 18 antibiotics were readily biodegradable. The HPLC analysis showed that some substances were partially or even completely disappeared by a non-biotic mechanism. In the case of some antibiotics, partial biological removal took place in test vessels containing readily biodegradable sodium acetate and the test compound. However, in the toxicity control, toxicity had not been eliminated.     

Environmentally compatible polymerization of olefins by the use of metallocene catalysts

Polyolefins belong to the most non-polluting mass polymers since they consist of carbon and hydrogen, only. Additionally the pure polymers can be easily reused, they can be decomposed into their monomer building blocks or they can be burned to carbon dioxide and water under production of energy. With metallocene catalysts the efficiency of the polymerization compared to the common "Ziegler-Natta" catalysts can be increased by the factor of 10-100. Therefore, resources are saved and energy costs decreased. The metallocene catalysts allow in a so far unknown fashion the synthesis of polymers in a very distinctive way. By variation of the ligand structure it is possible to influence as well the microstructure of the polymers as the stereo- and regio-selectivity and the tacticity in a broad range. Therefore, the production of polymers with outstanding mechanical properties becomes possible, so far these were reserved for high-performance polymers, which can be only made with high efforts and less environmentally compatible.