Determination of total and available fractions of PAHs by SPME in oily wastewaters: overcoming interference from NAPL and NOM

Background, aim, and scope  

Polycyclic aromatic hydrocarbons (PAHs) are often found in oily wastewaters. Their presence is usually the result of human activities and has a negative effect on the environment. One important step in addressing this problem is to evaluate the effectiveness of PAH removal by biological processes since these are the most cost-effective treatments known today. Many techniques are presently available for PAH determination in wastewaters. Solid phase microextracion (SPME) is known to be one of the most effective techniques for this purpose. When analyzing complex matrices with substances such as natural organic matter (NOM) and non-aqueous phase liquids (NAPL), it is important to differentiate the free dissolved PAH from matrix-bonded PAH. PAHs associated with the bonded fraction are less susceptible to biological treatment. The present study concerns the development of a simple and suitable methodology for the determination of the freely dissolved and the total fraction of PAHs present in oily wastewaters. The methodology was then applied to an oily wastewater from a fuel station retention basin.     

Temporal pessimism and spatial optimism in environmental assessments: An 18-nation study

The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies.     

Indicating ecosystem integrity — theoretical concepts and environmental requirements

This paper discusses some conceptual fundamentals for the derivation of environmental indicator sets. On the one hand, it defines requirements from environmental politics, environmental management and legislation, reaching from political target hierarchies and sustainable management strategies to holistic protection concepts such as process protection, resource preservation, ecosystem health and ecological integrity. On the other hand, demands from ecosystem theory are described which include the consideration of features such as self-organization, emergence, thermodynamics, gradients and ecological orientors in environmental indicator sets. From that concept, collective and emergent properties are selected and eight holistic ecosystem features are presented that indicate the ecosystemic state as an ensemble. These general indicators of ecosystem integrity are supplemented by variables on structural changes and substance dynamics.     

Remediation aspect of microbial changes of plant rhizosphere in mercury contaminated soil

Phytoremediation, an approach that uses plants to remediate contaminated soil through degradation, stabilization or accumulation, may provide an efficient solution to some mercury contamination problems. This paper presents growth chamber experiments that tested the ability of plant species to stabilize mercury in soil. Several indigenous herbaceous species and Salix viminalis were grown in soil collected from a mercury-contaminated site in southern Poland. The uptake and distribution of mercury by these plants were investigated, and the growth and vitality of the plants through a part of one vegetative cycle were assessed. The highest concentrations of mercury were found at the roots, but translocation to the aerial part also occurred. Most of the plant species tested displayed good growth on mercury contaminated soil and sustained a rich microbial population in the rhizosphere. The microbial populations of root-free soil and rhizosphere soil from all species were also examined. An inverse correlation between the number of sulfur amino acid decomposing bacteria and root mercury content was observed. These results indicate the potential for using some species of plants to treat mercury contaminated soil through stabilization rather than extraction. The present investigation proposes a practical cost-effective temporary solution for phytostabilization of soil with moderate mercury contamination as well as the basis for plant selection.     

A proposed impact assessment method for genetically modified plants (AS-GMP Method)

An essential step in the development of products based on biotechnology is an assessment of their potential economic impacts and safety, including an evaluation of the potential impact of transgenic crops and practices related to their cultivation on the environment and human or animal health. The purpose of this paper is to provide an assessment method to evaluate the impact of biotechnologies that uses quantifiable parameters and allows a comparative analysis between conventional technology and technologies using GMOs. This paper introduces a method to perform an impact analysis associated with the commercial release and use of genetically modified plants, the Assessment System GMP Method. The assessment is performed through indicators that are arranged according to their dimension criterion likewise: environmental, economic, social, capability and institutional approach. To perform an accurate evaluation of the GMP specific indicators related to genetic modification are grouped in common fields: genetic insert features, GM plant features, gene flow, food/feed field, introduction of the GMP, unexpected occurrences and specific indicators. The novelty is the possibility to include specific parameters to the biotechnology under assessment. In this case by case analysis the factors of moderation and the indexes are parameterized to perform an available assessment.     

Evaluation of various chemical extraction methods to estimate plant-available arsenic in mine soils

Elevated levels of bioavailable As in mining soils, agricultural areas and human habitats may cause potential toxicity to human health, plants and microbe. Therefore, it is essential to determine proper soil chemical extraction method in order to estimate plant-available As in mining soils and protect agricultural and environmental ecosystems by evaluation of environmental risk and implementation of remediation measures. In this study, six single soil chemical extraction processes and four-step sequential chemical extraction protocol were used to determine the relative distribution of As in different chemical forms of soils and their correlations with total As in plants grown in mining areas and greenhouse experiments. The strongest relationship between As determined by single soil chemical extraction and As in plant biomass was found for sodium acetate and mixed acid extractant. The mean percent of total As extracted was: ammonium oxalate (41%)>hydroxylamine hydrochloride (32%)>mixed acid (16%)>phosphate (6%)>sodium acetate (1.2%)>water (0.13%). This trend suggests that most of the As in these soils is inside the soil mineral matrix and can only be released when iron oxides and other minerals are dissolved by the stronger chemical extractant. Single soil chemical extraction methods using sodium acetate and mixed acids, that extract As fractions complexed to soil particles or on the surface of mineral matrix of hydrous oxides of Fe, Mn and Al (exchangeable+sorbed forms) can be employed to estimate and predict the bioavailable As fraction for plant uptake in mining affected soils. In sequential chemical extraction methods, ammonium nitrate and hydroxylamine hydrochloride may be used to provide closer estimates of plant-available As in mining soils.     

Trisomy 10: ultrasound features and natural history after first trimester diagnosis

We report on the ultrasound features and natural history of trisomy 10. At 12 weeks' gestation in a routine scan examination, the fetus presented with increased nuchal translucency thickness, mild skin oedema, bilateral pleural effusion, marked micrognathia, cardiomegaly, unilateral talipes and reversed A-wave in the ductus venosus blood flow. Karyotyping on chorionic villus sampling (CVS) led to the diagnosis of trisomy 10, which was confirmed by fetal blood sampling at 22 weeks' gestation. As the parents opted to continue with the pregnancy, the natural history and following ultrasound features are described. This is the third case of trisomy 10 in the literature reporting on the physical features. The most frequent ultrasound findings presented in trisomy 10 are increased nuchal translucency, micrognathia, renal agenesis, facial cleft, limbabnormalities, cardiac defects and early severe growth retardation. Copyright © 2001 John Wiley & Sons, Ltd.     

Old models explain new observations of butterfly movement at patch edges

Understanding movement in heterogeneous environments is central to predicting how landscape changes affect animal populations. Several recent studies point out an intriguing and distinctive looping behavior by butterflies at habitat patch edges and hypothesize that this behavior requires a new framework for analyzing animal movement. We show that this looping behavior could be caused by a longstanding movement model, biased correlated random walk, with bias toward habitat patches. The ability of this longstanding model to explain recent observations reinforces the point that butterflies respond to habitat heterogeneity and do not move randomly through heterogeneous environments. We discuss the implications of different movement models for predicting butterfly responses to landscape change, and our rationale for retaining longstanding movement models, rather than developing new modeling frameworks for looping behavior at patch edges.     

Survey of mercury,cadmium and lead content of household batteries

The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline–manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc–carbon batteries, on average, contained the highest levels.