Daily, seasonal and monthly variations in ozone levels recorded at the Turia river basin in Valencia (Eastern Spain)

Introduction

The Turia river basin, located in the east of the Iberian Peninsula, drains into the Mediterranean Sea near the city of Valencia (population, 814,208). The predominance of sea-breeze fluxes favours the inland transport of pollutants from the city up the basin where ozone concentrations exceeding the threshold for protection of human health are systematically recorded during the summer months.

Methods

This work analyses the variability in ozone levels by examining their spatial and temporal distribution in a Mediterranean river basin downwind from a city within the period 2005?C2008. Orographic determinants and atmospheric fluxes induce strong variations in ozone measurements, even on relatively close locations.

Conclusions

Results show a different behaviour of the monthly means and the daily cycles depending on the season of the year and the measuring environment, with summer/winter ratios ranging from 2.4 in cities to 1.6 inland, and mean values always higher in the interior of the basin. Daily cycles show significant summer/winter differences related to the predominant situations of anticyclonic stability in winter, which limit ventilation, and the predominant breeze circulations in summer. Results also show a ??weekend effect?? at urban and medium-distance stations. At the most inland station, the weekend/weekday behaviour differs according to the season of the year; weekend ozone levels are higher in spring, autumn and winter, and lower in summer, coinciding with the predominance of local wind cycles that favour air mass penetration inland from the coast.     

A tiered ecological risk assessment of three chlorophenols in Chinese surface waters

Introduction

The ecological risks posed by three chlorophenols (CPs), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) in Chinese surface waters were assessed.

Materials and methods

This was achieved by applying a tiered ecological risk assessment (ERA) approach ranging from deterministic methods to probabilistic options to measured concentrations of CPs in surface water of seven major watersheds and three drainage regions in China and the chronic toxicity data for indigenous Chinese species.

Results and discussion

The results show that the risks of three chlorophenols are ranked PCP>2,4-DCP??2,4,6-TCP. PCP posed little ecological risk while 2,4-DCP and 2,4,6-TCP posed negligible or de minimis risk in Chinese surface water. However, the risks varied with different river basins, for example, PCP posed some ecological risk in the Yangtze, Huaihe, and Pearl Rivers. The magnitude of 2,4-DCP and 2,4,6-TCP pollution in North China was more serious than that in South China.

Conclusion

The probabilistic risk assessment approach, which can provide more information for risk managers and decision makers, was favored over the screening-level single-value estimate method. However, the results from all tiers of the ERA methods in the framework were consistent with each other.     

Exposure assessment of pesticides in a shallow groundwater of the Tagus vulnerable zone (Portugal): a multivariate statistical approach (JCA)

Purpose

To assess groundwater exposure to pesticides, in agricultural areas of ??Ribatejo?? region (Portugal), and the influence of some key factors in that exposure, field, laboratory and modelling studies were carried out.

Methods

The study was performed in maize, potato, sugar beet, tomato and vegetables agricultural areas, located in a shallow aquifer, with pesticides use and, in most cases, with irrigation practices. Pesticides used in the studied agricultural areas and having leaching potential were selected, being considered also other pesticides included in priority lists, defined in Europe. Evaluation of groundwater exposure to pesticides was carried out by successively: (1) groundwater sampling in seven campaigns over the period 2004?C2006; (2) pesticide analysis [including isolation and concentration from the groundwater samples and further determination by gas chromatography?Cmass spectrometry (GC?CMS) of 14 herbicides, four insecticides and two metabolites]; and (3) analysis and discussion of the results by applying joint correspondence analysis (JCA).

Results

From the 20 pesticides and metabolites selected for the study, 11 were found in groundwater. Pesticides and metabolites most frequently detected were atrazine, alachlor, metolachlor, desethylatrazine, ethofumesate, ??-endosulfan, metribuzine, lindane and ??-endosulfan. The results showed that groundwater exposure to pesticides is influenced by local factors??either environmental or agricultural, as precipitation, soil, geology, crops and irrigation practices. Spring and autumn were more associated with the detection of pesticides being more likely to observe mixtures of these compounds in a groundwater sample in these transition seasons.

Conclusions

This work evidences the importance of models, which evaluate pesticides environmental behaviour, namely their water contamination potential (as Mackay multicompartimental fugacity model) and, specially, groundwater contamination potential (as GUS and Bacci and Gaggi leaching indices), in pesticide selection. Moreover, it reveals the importance to adapt proper statistical methods according to level of left-censored data. Using JCA was still possible to establish relations between pesticides and their temporal trend in a case study where there were more than 80% of data censored. This study will contribute to the Tagus river basin management plan with information on the patterns of pesticide occurrence in the alluvial aquifer system.     

Synthesis, properties and application research of atrazine Fe3O4@SiO2 magnetic molecularly imprinted polymer

Introduction

Magnetic Fe₃O₄ nanoparticles were prepared by coprecipitation and then were coated with SiO₂ on the surface.

Materials and methods

Fe₃O₄@SiO₂ composite microspheres were modified by KH570. Using molecular imprinting technology, atrazine magnetic molecularly imprinted polymer was prepared by using atrazine as template molecule, methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linkers. The morphology, composition and magnetic properties of magnetic nanoparticles were characterized. The recognition selectivity of polymer was studied for template molecule and simulation by UV spectrophotometry. The adsorption properties and selectivity ability were analyzed by Scatchard analysis.

Results

Scatchard linear regression analysis indicated that there are two binding sites of the target molecules. The magnetic molecularly imprinted polymer has been applied to the analysis of atrazine in real samples.

Conclusion

The results show that: the recovery rates and the relative standard deviation were 94.0??98.7% and 2.1??4.0% in corn, the recovery rates and the relative standard deviation were 88.7??93.5% and 2.8??7.2% in water.     

Evaluation of hexachlorocyclohexane contamination from the last lindane production plant operating in India

Purpose

??-Hexachlorocyclohexane (HCH), ??-HCH, and lindane (??-HCH) were listed as persistent organic pollutants by the Stockholm Convention in 2009 and hence must be phased out and their wastes/stockpiles eliminated. At the last operating lindane manufacturing unit, we conducted a preliminary evaluation of HCH contamination levels in soil and water samples collected around the production area and the vicinity of a major dumpsite to inform the design of processes for an appropriate implementation of the Convention.

Methods

Soil and water samples on and around the production site and a major waste dumpsite were measured for HCH levels.

Results

All soil samples taken at the lindane production facility and dumpsite and in their vicinity were contaminated with an isomer pattern characteristic of HCH production waste. At the dumpsite surface samples contained up to 450?g?kg^?1 ?? HCH suggesting that the waste HCH isomers were simply dumped at this location. Ground water in the vicinity and river water was found to be contaminated with 0.2 to 0.4?mg?l^?1 of HCH waste isomers. The total quantity of deposited HCH wastes from the lindane production unit was estimated at between 36,000 and 54,000?t.

Conclusions

The contamination levels in ground and river water suggest significant run-off from the dumped HCH wastes and contamination of drinking water resources. The extent of dumping urgently needs to be assessed regarding the risks to human and ecosystem health. A plan for securing the waste isomers needs to be developed and implemented together with a plan for their final elimination. As part of the assessment, any polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) generated during HCH recycling operations need to be monitored.     

Adsorption and photodegradation of microcystin-LR onto sediments collected from reservoirs and rivers in Taiwan: a laboratory study to investigate the fate, transfer, and degradation of microcystin-LR

Background, aim, and scope

This study demonstrated the adsorption capacity of microcystin-LR (MC-LR) onto sediment samples collected from different reservoirs (Emerald and Jade reservoirs) and rivers (Dongshan, Erhjen, and Wukai rivers) in Taiwan to investigate the fate, transport behavior, and photodegradation of MC-LR.

Main features

Langmuir adsorption and photodegradation studies were carried out in the laboratory and tested the capability of sediments for MC-LR adsorption. These data suggested that sediments play a crucial role in microcystins degradation in aquatic systems.

Results and discussion

The results of batch experiments revealed that the adsorption of MC-LR varied significantly with texture, pH, and organic matter content of sediments. Silty and clay textures of the samples were associated with larger content of organic matter, and they displayed the enhanced MC-LR adsorption. Low pH sediment showed increased adsorption of MC-LR. The effective photodegradation of MC-LR (1.6 ??g/mL) was achieved within 60 min under 254 nm light irradiation.

Conclusion

A comparative study of adsorption capacity of all sediment samples was carried out and discussed with respect to different aspects. Among all, sediments collected from Jade reservoir showed enhanced MC-LR adsorption (11.86 ??g/g) due to favored textural properties (BET surface area = 20.24 m2/g and pore volume = 80.70 nm).

Perspectives

These data provide important information that may be applied to management strategies for improvement of water quality in reservoirs and rivers and other water bodies in Taiwan.     

China’s wastewater discharge standards in urbanization

Background and purpose

China's environmental problems and pollution control have global implications. China??s water pollution has been increasing with its urbanization and industrialization. Although great efforts have been taken to keep its wastewater discharge standards in pace with the water pollution development and technological advances, many challenges remain. A summary of the past achievements and lessons as well as the current problems in water pollution may provide a basis for future improvements in China and a reference for other countries.

Methods

Statistical data are summarized to reveal the evolution of China??s population, wastewater discharge and corresponding discharge standards over the past four decades. In particular, the specific control indexes and number of controlled items are discussed in details. The present water pollution situation is clearly illustrated by the water pollution map and the water quality distribution diagram. A comparison between China??s present wastewater discharge standards and those in the USA and the EU are also presented to find the possibilities for future improvement.

Results

The historical origins, major challenges and future perspectives of China??s wastewater discharge standards are overviewed. The barriers and ongoing efforts for standards formulation and implementation are highlighted. Some suggestions for future endeavors are given.

Conclusions

China??s wastewater discharge standard system has seen significant improvement over the past decades, but it still has many defects and limitations. Nonetheless, unprecedented great efforts are underway to address all these challenges. More stringent standards and subsequently a cleaner water environment in China can be expected in the near future.     

Evaluation of environmental impact produced by different economic activities with the global pollution index

Introduction

The paper analyses the environment pollution state in different case studies of economic activities (i.e. co-generation electric and thermal power production, iron profile manufacturing, cement processing, waste landfilling, and wood furniture manufacturing), evaluating mainly the environmental cumulative impacts (e.g. cumulative impact against the health of the environment and different life forms).

Materials and methods

The status of the environment (air, water resources, soil, and noise) is analysed with respect to discharges such as gaseous discharges in the air, final effluents discharged in natural receiving basins or sewerage system, and discharges onto the soil together with the principal pollutants expressed by different environmental indicators corresponding to each specific productive activity. The alternative methodology of global pollution index (I _GP ^* ) for quantification of environmental impacts is applied.

Results and discussion

Environmental data analysis permits the identification of potential impact, prediction of significant impact, and evaluation of cumulative impact on a commensurate scale by evaluation scores (ES_i) for discharge quality, and global effect to the environment pollution state by calculation of the global pollution index (I _GP ^* ).

Conclusions

The I _GP ^* values for each productive unit (i.e. 1.664?C2.414) correspond to an ??environment modified by industrial/economic activity within admissible limits, having potential of generating discomfort effects??. The evaluation results are significant in view of future development of each productive unit and sustain the economic production in terms of environment protection with respect to a preventive environment protection scheme and continuous measures of pollution control.     

Perfluorooctane sulfonate increases β-oxidation of palmitic acid in chicken liver

Purpose

Perfluorooctane sulfonate (PFOS) belongs to a group of chemicals called perfluoroalkyl acids that have been extensively used in various applications such as stain and oil resistant treatments for fabrics, fire-fighting foams, and insecticides. These chemicals present an environmental and health risk being present in many samples both in wildlife and humans. In this study, we investigate the effect of PFOS on fatty acid ??-oxidation in developing chicken embryos.

Methods

Fertilized chicken eggs were exposed in ovo to PFOS at day?4 of incubation. On day?10, the eggs were dissected and livers were incubated in vitro with ³H-palmitic acid for 2?h. The media were collected, and after clean up, the amount of tritiated water was measured with liquid scintillation counting to determine the rate of palmitic acid ??-oxidation.

Results

PFOS was found to induce fatty acid ??-oxidation at doses starting from a lowest observed effect level (LOEL) of 0.1???g/g egg weight. Maximum induction of 77?% compared to control was seen at 0.3???g/g.

Conclusions

The administered doses in which effects are seen are around and even lower than the levels that can be found in wild populations of birds. General population human levels are a factor of two to three times lower than the LOEL value of this study. The environmental contamination of PFOS therefore presents a possibility of effects in wild populations of birds.     

Spatiotemporal distributions of nutrients in the downstream from Gezhouba Dam in Yangtze River, China

Introduction

From December 2008 to November 2009, an investigation of water quality was performed in the 70-km long downstream from Gezhouba Dam in Yangtze River.

Methods

Twelve sites in all were chosen. Nine parameters of water quality including the total phosphorus, the total nitrogen, chlorophyll a (Chl.a), nitrite, nitrate, ammonia, water temperature, DO, and pH were monitored almost monthly. The multivariate statistical technique (cluster analysis) and the nonparametric method (Kruskal?CWallis Test and Spearman??s rank correlation) were applied to evaluate the spatiotemporal variations of water quality data sets.

Results and discussion

According to the Chinese environmental quality standards for surface water (GB3838-2002), the water quality in the river section investigated can attain to the III water standards except total nitrogen. Further analysis indicated that there were no significant spatial differences in these parameters of water quality, but the sampling date had a significant effect. The temporal variation of water quality can be related to the discharge of Gezhouba Dam and moreover be affected by the reservoir regulation. During the discharge, the discharge increased the concentration of total phosphorus and then decreased the N:P ratio, which helps to the occurrence of algae blooms. The high consternation of phosphorus and the low N:P ratio show that the water body can be in the process of eutrophication during the discharge of Gezhouba Dam. In fact, Chl.a had begun to rise in the same period.     

Microbial structure and chemical components of aerosols caused by rotating brushes in a wastewater treatment plant

Purpose

Bacterial community structure and the chemical components in aerosols caused by rotating brushes in an Orbal oxidation ditch were assessed in a Beijing municipal wastewater treatment plant.

Methods

Air samples were collected at different distances from the aerosol-generating rotating brushes. Molecular culture-independent methods were used to characterize the community structure of the airborne bacteria in each sample regardless of cell culturability. A clone library of 16S rDNA directly amplified from air DNA of each sample was constructed and sequenced to analyze the community composition and diversity. Insoluble particles and water-soluble ions emitted with microorganisms in aerosols were analysis by a scanning electron microscope together with energy dispersive X-ray spectroscopy and ion chromatogram analyzer.

Results

In total, most of the identified bacteria were Proteobacteria. The majority of sequences near the rotating brushes (the main source of the bioaerosols) were Proteobacteria (62.97 %) with ??-(18.52 %) and ??-(44.45?%) subgroups and Bacteroidetes (29.63 %). Complex patterns were observed for each sampling location, suggesting a highly diverse community structure, comparable to that found in water in the Orbal oxidation ditch. Accompany with microorganisms, 46.36???g/m³ of SO ₄ ^2? , 29.35???g/m³ of Cl^?, 21.51???g/m³ of NO ₃ ^? , 19.76???g/m³ of NH ₄ ⁺ , 11.42???g/m³ of PO ₄ ^3? , 6.18???g/m³ of NO ₂ ^? , and elements of Mg, Cl, K, Na, Fe, S, and P were detected from the air near the aerosols source.

Conclusions

Differences in the structure of the bacterial communities and chemical components in the aerosols observed between sampling sites indicated important site-related variability. The composition of microorganisms in water was one of the most important sources of bacterial communities in bioaerosols. Chemical components in bioaerosols may provide a media for airborne microorganism attachment, as well as a suitable microenvironment for their growth and survival in the air. This study will be benefit for the formulation of pollution standards, especially for aerosols, that take into account plant workers?? health.     

Occurrence of psychoactive compounds and their metabolites in groundwater downgradient of a decommissioned sewage farm in Berlin (Germany)

Purpose

Psychoactive compounds??meprobamate, pyrithyldione, primidone, and its metabolites, phenobarbital, and phenylethylmalonamide??were detected in groundwater within the catchment area of a drinking water treatment plant located downgradient of a former sewage farm in Berlin, Germany. The aim of this study was to investigate the distribution of the psychoactive compounds in anoxic groundwater and to assess the risk of drinking water contamination. Groundwater age was determined to achieve a better understanding of present hydrogeological conditions.

Methods

A large number of observation and production wells were sampled. Samples were analyzed using solid-phase extraction and ultrahigh-performance liquid chromatography?Ctandem mass spectrometry. Groundwater age was estimated using the helium?Ctritium (³He?C³H) dating method.

Results

Concentrations of psychoactive compounds up to 1???g/L were encountered in the contamination plume. Generally, concentrations of phenobarbital and meprobamate were the highest. Elevated concentrations of the analytes were also detected in raw water from abstraction wells located approximately 2.5?km downgradient of the former sewage farm. Concentrations in the final drinking water were below the limit of quantification owing to dilution. The age of shallow groundwater samples ranged from years to a decade, whereas groundwater was up to four decades old at 40?m below ground. Concentrations of the compounds increased with groundwater age.

Conclusions

Elevated concentrations of psychoactive drugs indicate a strong persistence of these compounds in the environment under anoxic aquifer conditions. Results suggest that the heritage of sewage irrigation will affect raw water quality in the area for decades. Therefore, further monitoring of raw and final drinking water is recommended to ensure that contaminant concentrations remain below the health-based precautionary value.     

Lead concentration increase in the hepatic and gill soluble fractions of European chub (Squalius cephalus)—an indicator of increased Pb exposure from the river water

Purpose

To examine if chronic exposure of feral fish to elevated Pb concentrations in the river water (up to 1???g?L^?1), which are still lower than European recommendations for dissolved Pb in surface waters (7.2???g?L^?1; EPCEU (Official J L 348:84, 2008)), would result in Pb accumulation in selected fish tissues.

Methods

Lead concentrations were determined by use of HR ICP-MS in the gill and hepatic soluble fractions of European chub (Squalius cephalus) caught in the Sutla River (Croatia?CSlovenia).

Results

At the site with increased dissolved Pb in the river water, soluble gill Pb levels (17.3???g?L^?1) were approximately 20 times higher compared to uncontaminated sites (0.85???g?L^?1), whereas the ratio between contaminated (18.1???g?L^?1) and uncontaminated sites (1.17???g?L^?1) was lower for liver (15.5). Physiological variability of basal Pb concentrations in soluble gill and hepatic fractions associated to fish size, condition, sex, or age was not observed, excluding the possibility that Pb increase in chub tissues at contaminated site could be the consequence of studied biotic parameters. However, in both tissues of Pb-exposed specimens, females accumulated somewhat more Pb than males, making female chubs potentially more susceptible to possible toxic effects.

Conclusions

The fact that Pb increase in gill and hepatic soluble fractions of the European chub was not caused by biotic factors and was spatially restricted to one site with increased dissolved Pb concentration in the river water points to the applicability of this parameter as early indicator of Pb exposure in monitoring of natural waters.     

TiO2/β-SiC foam-structured photoreactor for continuous wastewater treatment

Introduction

This study of photocatalytic degradation of wastewater was carried out in alveolar cell ??-SiC foam-structured photocatalytic reactors working in a recirculation mode. The immobilization of TiO2 on ??-SiC foams was efficiently obtained through a sol?Cgel technique in acidic conditions.

Discussion

In order to optimize degradation yields obtained by the foam-structured prototype reactor for the photocatalytic water treatment, the operating conditions of the photoreactor have been investigated and the efficiency of the process was evaluated by measuring the photocatalytic degradation of Diuron (3-(3,4-dichlorophenyl)-1,1-dimethyl-urea)) under UV irradiation. Kinetic studies were carried out by investigating the influence of different parameters controlling the reaction (TiO2 loading and ??-SiC foam cell size). The ageing of TiO2/??-SiC foam photocatalytic materials and the mineralization (TOC, Cl?, NO3? and NH4+) of Diuron were investigated.     

Perfluorooctanoic acid and perfluorooctane sulfonate released from a waste water treatment plant in Bavaria, Germany

Purpose

Perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and precursors and derivatives thereof have been employed as surfactants and anti-adhesives. PFOA and PFOS are environmentally persistent and the discharge of municipal waste waters is one of the principal routes of these compounds into the aquatic environment. In a previous study, the concentrations of PFOA and PFOS in grab samples collected from the waste water treatment plant (WWTP) of Bayreuth, a city of 72,000 inhabitants in Bavaria, Germany, during two periods showed considerable variability. For a better estimate of average mass flows, the surfactants were monitored (five samplings) from 16 March to 18 May 2007. In a second campaign, river water receiving the WWTP effluent was sampled twice a day for five consecutive days.

Methods

Quantitative analysis was done by stable-isotope dilution, pre-cleaning, and pre-concentration by solid-phase extraction, and liquid chromatography followed by electrospray ionization/tandem mass spectrometry.

Results

The mass flows of PFOA and PFOS through the WWTP were determined. PFOA is fully discharged into the river, while about half of PFOS is retained in the sewage sludge. The average daily mass load of the river Roter Main by the WWTP of Bayreuth is about 1.2?±?0.5 g PFOA and 5?±?2 g PFOS, with variations of up to 140% within one day.

Conclusion

Overall, the total annual release to the rivers of Germany may be in the range of several hundred kilograms of PFOA and several tons of PFOS.     

Climate and land-use changes affecting river sediment and brown trout in alpine countries—a review

Background, aim, and scope

Catch decline of freshwater fish has been recorded in several countries. Among the possible causes, habitat change is discussed. This article focuses on potentially increased levels of fine sediments going to rivers and their effects on gravel-spawning brown trout. Indications of increased erosion rates are evident from land-use change in agriculture, changes in forest management practices, and from climate change. The latter induces an increase in air and river water temperatures, reduction in permafrost, changes in snow dynamics and an increase in heavy rain events. As a result, an increase in river sediment is likely. Suspended sediment may affect fish health and behaviour directly. Furthermore, sediment loads may clog gravel beds impeding fish such as brown trout from spawning and reducing recruitment rates. To assess the potential impact on fine sediments, knowledge of brown trout reproductive needs and the effects of sediment on brown trout health were evaluated.

Approach

We critically reviewed the literature and included results from ongoing studies to answer the following questions, focusing on recent decades and rivers in alpine countries.

Have climate change and land-use change increased erosion and sediment loads in rivers?

Do we have indications of an increase in riverbed clogging?

Are there indications of direct or indirect effects on brown trout from increased suspended sediment concentrations in rivers or from an increase in riverbed clogging?

Results

Rising air temperatures have led to more intensive precipitation in winter months, earlier snow melt in spring, and rising snow lines and hence to increased erosion. Intensification of land use has supported erosion in lowland and pre-alpine areas in the second half of the twentieth century. In the Alps, however, reforestation of abandoned land at high altitudes might reduce the erosion risk while intensification on the lower, more easily accessible slopes increases erosion risk. Data from laboratory experiments show that suspended sediments affect the health and behaviour of fish when available in high amounts. Point measurements in large rivers indicate no common lethal threat and suspended sediment is rarely measured continuously in small rivers. However, effects on fish can be expected under environmentally relevant conditions. River bed clogging impairs the reproductive performance of gravel-spawning fish.

Discussion

Overall, higher erosion and increased levels of fine sediment going into rivers are expected in future. Additionally, sediment loads in rivers are suspected to have considerably impaired gravel bed structure and brown trout spawning is impeded. Timing of discharge is put forward and is now more likely to affect brown trout spawning than in previous decades.

Conclusions

Reports on riverbed clogging from changes in erosion and fine sediment deposition patterns, caused by climate change and land-use change are rare. This review identifies both a risk of increases in climate erosive forces and fine sediment loads in rivers of alpine countries. Increased river discharge and sediment loads in winter and early spring could be especially harmful for brown trout reproduction and development of young life stages. Recently published studies indicate a decline in trout reproduction from riverbed clogging in many rivers in lowlands and alpine regions. However, the multitude of factors in natural complex ecosystems makes it difficult to address a single causative factor.

Recommendations and perspectives

Further investigations into the consequences of climate change and land-use change on river systems are needed. Small rivers, of high importance for the recruitment of gravel-spawning fish, are often neglected. Studies on river bed clogging are rare and the few existing studies are not comparable. Thus, there is a strong need for the development of methods to assess sediment input and river bed clogging. As well, studies on the effects to fish from suspended sediments and consequences of gravel beds clogging under natural conditions are urgently needed.     

Adapting a geographical information system-based water resource management to the needs of the Romanian water authorities

Background, aim, and scope

The need for global and integrated approaches to water resources management, both from the quantitative and the qualitative point of view, has long been recognized. Water quality management is a major issue for sustainable development and a mandatory task with respect to the implementation of the European Water Framework Directive as well as the Swiss legislation. However, data modelling to develop relational databases and subsequent geographic information system (GIS)-based water management instruments are a rather recent and not that widespread trend. The publication of overall guidelines for data modelling along with the EU Water Framework Directive is an important milestone in this area. Improving overall water quality requires better and more easily accessible data, but also the possibility to link data to simulation models. Models are to be used to derive indicators that will in turn support decision-making processes. For this whole chain to become effective at a river basin scale, all its components have to become part of the current daily practice of the local water administration. Any system, tool, or instrument that is not designed to meet, first of all, the fundamental needs of its primary end-users has almost no chance to be successful in the longer term.

Materials and methods

Although based on a pre-existing water resources management system developed in Switzerland, the methodological approach applied to develop a GIS-based water quality management system adapted to the Romanian context followed a set of well-defined steps: the first and very important step is the assessment of needs (on the basis of a careful analysis of the various activities and missions of the water administration and other relevant stakeholders in water management related issues). On that basis, a conceptual data model (CDM) can be developed, to be later on turned into a physical database. Finally, the specifically requested additional functionalities (i.e. functionalities not provided by classical commercial GIS software), also identified during the assessment of needs, are developed. This methodology was applied, on an experimental basin, in the Ialomita River basin.

Results

The results obtained from this action-research project consist of a set of tangible elements, among which (1) a conceptual data model adapted to the Romanian specificities regarding water resources management (needs, data availability, etc.), (2) a related spatial relational database (objects and attributes in tables, links, etc.), that can be used to store the data collected, among others, by the water administration, and later on exploited with geographical information systems, (3) a toolbar (in the ESRI environment) offering the requested data processing and visualizing functionalities. Lessons learned from this whole process can be considered as additional, although less tangible, results.

Discussion

The applied methodology is fairly classical and did not come up with revolutionary results. Actually, the interesting aspects of this work are, on the one hand, and obviously, the fact that it produced tools matching the needs of the local (if not national) water administration (i.e. with a good chance of being effectively used in the day-to-day practice), and, on the other hand, the adaptations and adjustments that were needed both at the staff level and in technical terms.

Conclusions

This research showed that a GIS-based water management system needs to be backed by some basic data management tools that form the necessary support upon which a GIS can be deployed. The main lesson gained is that technology transfer has to pay much attention to the differences in existing situations and backgrounds in general, and therefore must be able to show much flexibility. The fact that the original objectives could be adapted to meet the real needs of the local end-users is considered as a major aspect in achieving a successful adaptation and development of water resources management tools. Time needed to setup things in real life was probably the most underestimated aspect in this technology transfer process.

Recommendations and perspectives

The whole material produced (conceptual data model, database and GIS tools) was disseminated among all river basin authorities in Romania on the behalf of the national water administration (ANAR). The fact that further developments, for example, to address water quantity issues more precisely, as envisaged by ANAR, can be seen as an indication that this project succeeded in providing an appropriate input to improve water quality in Romania on the long term.

     

Heterocatalytic Fenton oxidation process for the treatment of tannery effluent: kinetic and thermodynamic studies

Background, aim, scope

Treatment of wastewater has become significant with the declining water resources. The presence of recalcitrant organics is the major issue in meeting the pollution control board norms in India. The theme of the present investigation was on partial or complete removal of pollutants or their transformation into less toxic and more biodegradable products by heterogeneous Fenton oxidation process using mesoporous activated carbon (MAC) as the catalyst.

Materials and methods

Ferrous sulfate (FeSO₄·7H₂O), sulfuric acid (36?N, specific gravity 1.81, 98% purity), hydrogen peroxide (50% v/v) and all other chemicals used in this study were of analytical grade (Merck). Two reactors, each of height 50?cm and diameter 6?cm, were fabricated with PVC while one reactor was packed with MAC of mass 150?g and other without MAC served as control.

Results and discussion

The oxidation process was presented with kinetic and thermodynamic constants for the removal of COD, BOD, and TOC from the wastewater. The activation energy (Ea) for homogeneous and heterogeneous Fenton oxidation processes were 44.79 and 25.89?kJ/mol, respectively. The thermodynamic parameters ??G, ??H, and ??S were calculated for the oxidation processes using Van??t Hoff equation. Furthermore, the degradation of organics was confirmed through FTIR and UV?Cvisible spectroscopy, and cyclic voltammetry.

Conclusions

The heterocatalytic Fenton oxidation process efficiently increased the biodegradability index (BOD/COD) of the tannery effluent. The optimized conditions for the heterocatalytic Fenton oxidation of organics in tannery effluent were pH 3.5, reaction time?C4?h, and H₂O₂/FeSO₄·7H₂O in the molar ratio of 2:1.     

Distribution of organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) in marine sediments directly exposed to wastewater from Cortiou, Marseille

Introduction

The future ??Calanque National Park?? coastlines of the Bouches-du-Rh?ne and Var departments in France, constitute one of the ten biodiversity hot spots identified in the Mediterranean basin that receives industrial and urban wastewaters discharged from Marseille and its suburbs.

Materials and methods

Organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) were measured in sediments collected from 12 sampling sites (C1?CC12) of sewage discharge to the sea from the wastewater treatment plant of Cortiou-Marseille. This study aims to determine the extent of these compounds in the sediments and to establish the possible sources of these contaminants.

Results and discussion

Total pesticides in the sediments ranged from 1.2 to 190.6 ng g^-1 dry weight of sediment. The highest value was found at station C1, with a decreasing trend in total OC concentrations seaward. Among these compounds, the concentrations of the sum of dichlorodiphenyltrichloroethane (??DDT) were the highest, ranging from 0.7 to 114.3 ng g^-1. PCB concentrations, expressed as equivalent to Arochlor 1260, varied from 9.1 to 226.9 ng g^-1. Individually, the dominant coplanar PCB congeners CB-153, CB-138 and CB-101. Generally, PCB concentrations at stations C2, C3, C5 and C7 were higher than those at stations C10, C11 and C12. Through some pollution indices, we showed the long-term contamination input of these OCs (DDT, endosulfan, HCH and heptachlor cases) rather than a recent release resulting from degradation and long-term weathering (dieldrin, aldrin and methoxychlor cases). Occurrence of PCBs might be due to their resistance to degradation processes or/and chronic inputs.

Conclusions

By comparison with available sediment quality guideline (SQG) values, the environmental significance and toxicological implications of PCBs and OCs (i) reveal the probable adverse effects for the sediments from C1, C5, C6, C9 and (ii) confirm the adverse effect for marine biota and more particularly for benthic communities at C2?CC4, C7 and C8.     

In vitro metabolism of hydroxylated polybrominated diphenyl ethers and their inhibitory effects on 17β-estradiol metabolism in rat liver microsomes

Purpose

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have emerged as contaminants of environmental concerns because they pose potential risks to human and animal health. The purpose of this study was to investigate the in vitro metabolism of OH-PBDEs and their potential inhibition against 17??-estradiol (E2) metabolism.

Methods

Rat liver microsomes were used as a source of P450 enzymes in an in vitro metabolism study of OH-PBDEs. Inhibition of E2 metabolism and kinetic study were performed by incubating with rat liver microsomes in the presence of OH-PBDEs.

Results

The obtained data clearly demonstrated that OH-PBDEs, especially those congeners with lower bromination, could be metabolized to bromophenol and diOH-PBDEs. The less metabolic rate of OH-PBDEs was observed with the increasing number of bromine substituents. OH-PBDEs with hydroxyl group and bromine adjacent to the ether bridge showed faster metabolic rates. In addition, the results showed non-competitive inhibition of E2 metabolism by OH-PBDEs with IC₅₀ values in the range from 13.7 to 55.2???M. The most potent OH-PBDE inhibitor was found to be 3??-OH-BDE-100. The inhibitory potencies for OH-PBDEs were significantly higher than those of parent PBDE and methoxylated metabolites, providing the evidence that PBDEs exerted estrogenic activity in part by their hydroxylated metabolites.

Conclusions

OH-PBDEs exhibited large differences in their capacity to be metabolized and to inhibit E2 metabolism in rat liver microsomes. The finding might increase our understanding of healthy risk associated with PBDEs in human and wildlife.