Dealing with environmental legacy effects: the economic and social benefits of acid mine drainage remediation

This paper is concerned with developing a practical methodology for prioritising measures to ameliorate the environmental problems associated with the abandonment of mine workings. Although much attention is focused on the pollution associated with on-going industrial production, rather fewer resources are going to develop methodologies for handling the environmental legacy effects of our forefathers. Of the work that has been done, much of it tends to focus on single, incomplete measures or benefits. This paper looks at the particular issues of acid mine drainage (AMD) in the USA, and develops a tractable way of approaching the problem of how allocated resources may be prioritised to maximise net social benefits. In particular, it advocates the use of a combination of established methodologies with rather newer statistical procedures to approach the problem. It offers a number of case studies by way of illustration as to how the methodology can be applied.     

Study of the Kuznets environmental curve hypothesis from a global perspective 1960–2019: a semi-parametric panel data proposal

Environmental Science and Pollution Research - This work uses parametric and semiparametric panel data analysis methodologies to test the hypothesis of the environmental Kuznets curve, in 186...     

自然水体中主要有毒有机物的研究进展

介绍了主要有毒有机物多环芳烃(PAHs)、多氯联苯(PCBs)、有机氯农药(OCPs)在环境中的危害及其来源,着重评述了近年来中国自然水体中和沉积物中该类污染物的研究进展,指出新的检测技术的开发、有毒有机物的生殖毒性和生态环境风险影响方法学的研究及污染区域污染控制、消减及修复是今后该领域的工作重点.     

PCBQ: Computerized quantification of total PCB and congeners in environmental samples

Computerized methodologies for the quantification of total PCBs, PCB in Aroclor mixtures and individual PCB congeners in environmental samples are presented. The method for total PCBs is based on a multiple-linear regression analysis using data from capillary gas chromatography of Arocolor standards. PCB congeners were identified and their weight percentages determined in Aroclor mixtures by GC/MS. PCB congeners and total PCBs were accurately quantified in predetermined test data and environmental samples.     

Relation between the exergy of waste emissions and measures of environmental impact

In an attempt to improve methodologies for assessing and predicting environmental impact, the relation between several measures of environmental impact potential and exergy is investigated. Exergy is a measure of the degree of disequilibrium between a substance and its environment. The approach taken compares current methods used to assess the environmental impact potential of waste emissions and the exergy associated with those emissions. The measures of environmental impact potential considered are the Ontario 7le of industrial air emission limits, and two methods of assessing the environmental costs for air emissions resulting from the combustion of three common fossil fuels: coal, oil and natural gas. A relationship was identified between one environmental costing methodology and exergy. Further work appears to be justified, using more data, to verify this relation, and to detect other relationships between the exergy of waste emissions and measures of environmental impact.     

Enantiomer fractions of polychlorinated biphenyls in three selected Standard Reference Materials

The enantiomer composition of six chiral polychlorinated biphenyls (PCBs) were measured in three different certified Standard Reference Materials (SRMs) from the US National Institute of Standards and Technology (NIST): SRM 1946 (Lake Superior fish tissue), SRM 1939a (PCB Congeners in Hudson River Sediment), and SRM 2978 (organic contaminants in mussel tissue--Raritan Bay, New Jersey) to aid in quality assurance/quality control methodologies in the study of chiral pollutants in sediments and biota. Enantiomer fractions (EFs) of PCBs 91, 95, 136, 149, 174, and 183 were measured using a suite of chiral columns by gas chromatography/mass spectrometry. Concentrations of target analytes were in agreement with certified values. Target analyte EFs in reference materials were measured precisely (<2% relative standard deviation), indicating the utility of SRM in quality assurance/control methodologies for analyses of chiral compounds in environmental samples. Measured EFs were also in agreement with previously published analyses of similar samples, indicating that similar enantioselective processes were taking place in these environmental matrices.     

Economic Feasibility Study for Phosphorus Recovery Processes

Phosphorus recovery from wastewater has become a necessity for sustainable development because phosphorus is a non-renewable essential resource, and its discharge into the environment causes serious negative impacts. There are no economic incentives for the implementation of phosphorus recovery technologies because the selling price of rock phosphate is lower than phosphorus recovered from sewage. The methodologies used to determine the feasibility of such projects are usually focused on internal costs without considering environmental externalities. This article shows a methodology to assess the economic feasibility of wastewater phosphorus recovery projects that takes into account internal and external impacts. The shadow price of phosphorus is estimated using the directional distance function to measure the environmental benefits obtained by preventing the discharge of phosphorus into the environment. The economic feasibility analysis taking into account the environmental benefits shows that the phosphorus recovery is viable not only from sustainable development but also from an economic point of view.     

Accurate Chemical Analysis of MTBE in Environmental Media

The new millennium ushers in changes for refiners of automobile gasoline in the United States, as well as for the state and federal regulators who establish guidelines for gasoline formulation and environmental regulation governing the fate of gasoline-related chemicals in the nation's air, soil and groundwater. One current issue in the gasoline formulation debate centers on the comparison of the proven benefits of the addition of chemical oxygenates—especially methyltert -butyl ether (MTBE)—to gasoline (to improve tailpipe emission quality) against the presumed environmental problems caused by the presence of oxygenates in ground- and surface waters due to fugitive releases of gasoline. Credible debate on this subject presumes that current and past environmental monitoring data for MTBE in environmental samples is accurate and precise. Experience suggests that this assumption is not correct, in part because certain analytical methodologies—particularly older methods supported by the U.S. Environmental Protection Agency—can fall short of reasonable data quality goals for measurement of MTBE. This Technical Note summarizes the standard EPA methods available to site investigators who need to measure MTBE in environmental media, the limitations and advantages of these measurement techniques, and recommendations for improving these standard EPA methods to yield the highest quality MTBE environmental residue data.     

不确定性水质模型及其研究进展

水环境是一个充满不确定性因素的复杂巨系统,研究这些不确定性的变化有利于提高人们对水环境分析的认识和做出更切合实际的决策.详细、清晰地评述了不确定性水质模型研究的必要性、研究的方法和国内外研究进展等,并针对此类模型研究与应用过程中普遍存在的一些问题、主要表现和成因进行了分析与论述,最后结合目前的研究热点指出了今后不确定性水质模型发展的3个重要方向.     

Extraction and clean-up methods for organochlorine pesticides determination in milk

Organochlorine pesticides (OCPs) can cause environmental damage and human health risks since they are lipophilic compounds with high resistance to degradation and long half-lives in humans. As most persistent OCPs have been banned years ago, it is expected to find these compounds at trace levels in environment. Therefore, increasingly sensitive and reliable analytical techniques are required to ensure effective monitoring of these compounds. The aim of this review is to discuss extraction and clean-up methods used to monitor OCP residues in milk, reported in the last 20 years. To carry out this review, an exhaustive bibliographic review was conducted. Despite the disadvantages of conventional extraction and clean-up methods, such as liquid–liquid, solid-phase or Soxhlet extractions, these procedures are still used due to their reliability. New extraction methods, like solid-phase microextraction, matrix solid-phase dispersion or QuEChERS, have not been thoroughly evaluated for OCP determination in milk. Almost all the methodologies analyzed in this review presented good performance characteristics according to the performance acceptability criteria set in SANCO’s procedure. Comparison between limits of quantification (LOQ) and detection (LOD), for the reported methodologies, is not always possible due to the heterogeneity of the units. Thus, researchers should take into account an homogenization of LOD and LOQ units, according to the international regulations and MRLs established. Finally, more research is necessary to obtain the ideal methodology for OCPs determination in milk, which comprises the environmentally friendly characteristics of the new techniques and the reliability of the traditional methodologies.     

Improving estimation of indoor exposure to inhalable particles for children in the first year of life

There is growing scientific evidence linking early childhood exposure to environmental agents with asthma and other illnesses that may not appear until later in life. Unfortunately the direct measurement of personal exposures of children in the first year of life is not possible by existing methodologies. This study developed and evaluated a new methodology to better assess exposure of children to inhalable particles in the first year of life while involved in floor play in the home. We constructed the Pre-Toddler Inhalable Particulate Environmental Robotic (PIPER) sampler. Two series of measurements of inhalable particles were carried out. One collected filter samples of airborne inhalable particles and a second used a real-time total particle mass concentration monitor. Samples were collected for seven residential locations. Duplicate samples were collected with PIPER 20 cm above the floor and from an identical stationary monitor positioned at a height of 110 cm. The mean observed airborne inhalable particle concentrations measured by PIPER was 98.6 microg/ m3, whereas simultaneously collected stationary samples mean concentration was 49.8 microg/m3. The average observed ratio of PIPER samples to stationary samples was 2.4. A paired t test comparison of the two sampling methods indicated a statistically significant higher level of inhalable particle concentration measured by PIPER in comparison with the fixed sampler (P < 0.0001). Peak concentrations as measured by a real-time monitor were in excess of 3600 microg/m3. The results suggest that children playing on the floor are exposed to a higher concentration of total inhalable particles than previous methodologies estimate.     

Toxic Trace Elements Associated with Airborne Particulate Matter: A Review

This article provides a concise review of published literature pertaining to sampling and analytical methodologies, aerometric studies, source identification techniques and modeling activities for the elements arsenic, cadmium, nickel, lead, vanadium, zinc, cobalt, chromium, copper, iron, mercury, manganese, selenium and antimony, and their compounds, associated with airborne particulate matter. Sampling techniques discussed include filtration and inertial separation. Analytical methodologies such as atomic absorption and atomic emission spectrometry, neutron activation analysis, and X-ray fluorescence spectrometry are summarized. Data on atmospheric levels of 14 trace elements are presented in summary form from numerous studies in remote, rural and urban areas, and generally indicate that concentrations measured at rural locations are several orders of magnitude lower than those measured for urban areas. Source identification methodologies are discussed in terms of advantages and disadvantages, and various applications are cited for the following categories: size differentiation, enrichment factors, chemical mass balance, and multivariate models. Provided that reliable trace element data are available for both the source and the receptor, chemical mass balance and multivariate methods can account for up to 80 percent of all sources contributing to the observed ambient air concentration. Wet and dry deposition processes are reviewed and environmental measurement data are provided for each element for remote, rural and urban locations. Both wet and dry deposition fluxes need to be considered for trace elements when estimating the total annual amounts of various trace elements deposited at a particular locale. Global cycles and trace element budgets are introduced in the context of the types of models currently in use. Limitations include inadequate global scale surveys of heavy metal concentrations and the lack of knowledge of sources and/or sinks.     

New approaches to study the relationship between stomatal conductance and environmental factors under Mediterranean climatic conditions

The most frequently models used (Ball–Berry and Jarvis-type models) to estimate stomatal conductance (Gs) values have limitations when applied to plants growing in Mediterranean climate. To overcome these limitations, several statistical methodologies (Multiple Linear Regression, Neural Net Analysis (NNA)) were used to build models to predict Gs. However, all these models were unable to integrate the physiological response of plants to the overall limiting environmental parameters in our Mediterranean site especially during the summer drought. With this in mind, it is relevant to find alternative approaches which link Gs response to environmental limitations of plants. In this paper, we demonstrate that: (1) the different linear and nonlinear statistical approaches used significantly affect the weights of the environmental variables which are utilized in semi-empirical Gs models; (2) a tight relationship exists between summer values of Gs and the rate of accumulated precipitations (α) in the first 5 months of the year, thus allowing to predict Gs in a quantitative way; and (3) the latter is also related to different water-use strategies adopted by plants in response to drought stress in the summer period. Because α is easily calculated, it is an interesting parameter for the Gs modelling addressed to understand many important aspects of the plant–environment interactions, such as water relations and pollutant uptake.     

Enantiomer fractions of chiral organochlorine pesticides and polychlorinated biphenyls in standard and certified reference materials

Enantiomeric ratios (ERs) and enantiomeric fractions (EFs) of a number of chiral organochlorine pesticides and PCB atropisomers were measured by chiral gas chromatography/mass spectrometry (GC/MS) in five standard (SRM) and certified (CRM) reference materials: SRM 1588a (organics in cod liver oil), SRM 1945 (organics in whale blubber), Marine Mammal Quality Assurance Exercise Control Material IV (NIST IV, organics in whale blubber), CRM trout, and CRM EC-5 (sediment). Target analytes were cis- and trans-chlordane, heptachlor exo-epoxide, oxychlordane, U82, MC5, MC6, MC7, o,p^′-DDT, and PCB congeners 91, 95, 136, 149, 174, 176, and 183. Measured ERs and EFs are in close agreement with the few literature values reported for some of these analytes in SRMs and CRMs. Chiral PCB ERs and EFs measured by one-dimensional chiral GC/MS were similar to values measured using multidimensional chiral GC/MS. Non-racemic chiral compositions are in agreement with known uptake and biotransformation in the respective environmental matrices. These values should aid in the quality assurance/quality control methodologies for chiral environmental chemistry using standardized reference materials.     

Spatial modeling of factor analysis scores

The use of mosses as biomonitors operates as an indicator of their concentration in the environment, becoming a methodology which provides a significant interpretation in terms of environmental quality. The different types of pollution are variables that can not be measured directly in the environment - latent variables. Therefore, we propose the use of factor analysis to estimate these variables in order to use them for spatial modelling. On the contrary, the main aim of the commonly used principal components analysis method is to explain the variability of observed variables and it does not permit to explicitly identify the different types of environmental contamination. We propose to model the concentration of each heavy metal as a linear combination of its main sources of pollution, similar to the case of multiple regression where these latent variables are identified as covariates, though these not being observed. Moreover, through the use of geostatistical methodologies, we suggest to obtain maps of predicted values for the different sources of pollution. With this, we summarize the information acquired from the concentration measurements of the various heavy metals, and make possible to easily determine the locations that suffer from a particular source of pollution.     

Microplastics in aquatic environment: characterization,ecotoxicological effect,implications for ecosystems and developments in South Africa

Microplastics are small-size plastic piece scales (particles <?5 mm) in sediments and waters which interact with environment and organisms by various means. Microplastics are becoming a universal ecological concern since they may be a source of hazardous chemicals to marine organisms and environments. Recent research suggests microplastics could enable the transfer of hydrophobic aquatic pollutants or chemical additives to biota. Even though microplastic presence and interactions are recently being detected in marine and freshwater systems, the fate of microplastics is still very poorly understood. This literature review is a summary of the sources and transport of microplastics, their interactions with toxic chemicals and the methodologies for chemical quantification and characterization of microplastics. The environmental outcome and impact of microplastics in wastewater treatment plants were assessed as well as the trends and update on microplastic research in the South African aquatic ecosystem.

     

Estimation and projection of nitrous oxide (N2O) emissions from anthropogenic sources in Taiwan

Taiwan is a densely populated and developed country with more than 97% of energy consumption supplied by imported fuels. Greenhouse gas emissions are thus becoming significant environmental issues in the country. Using the Intergovernmental Panel on Climate Change (IPCC) recommended methodologies, anthropogenic emissions of nitrous oxide (N2O) in Taiwan during 2000-2003 were estimated to be around 41 thousand metric tons annually. About 87% of N2O emissions come from agriculture, 7% from the energy sector, 3% from industrial processes sector, 3% from waste sector. On the basis of N2O emissions in 2000, projections for the year 2010 show that emissions were estimated to decline by about 6% mainly due to agricultural changes in response to the entry of WTO in 2002. In contrast to projections for the year 2020, N2O emissions were projected to grow by about 17%. This is based on the reasonable scenario that a new adipic acid/nitric acid plant will be probably started after 2010.     

Chapter two: methodologies for characterisation of combustion sources and for quantification of their emissions

Emissions from the combustion of biomass and fossil fuels result in generation of a large number of particle and gaseous products in outdoor and/or indoor air, which create health and environmental risks. Of particular importance are the very small particles that are emitted in large quantities from all the combustion sources, and that could be potentially more significant in terms of their impact on health and the environment than larger particles. It is important to quantify particle emissions from combustion sources for regulatory and control purposes in relation to air quality. This paper is a review of particle characteristics that are used as source signatures, their general advantages and limitations, as well as a review of source signatures of the most common combustion pollution sources including road transport, industrial facilities, small household combustion devices, environmental tobacco smoke, and vegetation burning. The current methods for measuring particle physical characteristics (mass and number concentrations) and principles of methodologies for measuring emission factors are discussed in the paper as well. Finally, the paper presents the recommendations for the future techniques for measurements of combustion products.