Hydrolytic biodegradation of chlorothalonil in the soil and in cabbage crops

Broccoli and Chinese cabbage crops were treated at planting by pouring an emulsion of the fungicide chlorothalonil around the stem of the plant. During culture, chlorothalonil was biodegraded in soil into l,3‐dicarbamoyl‐2,4,5,6‐tetrachlorobenzene (compound 1), l,3‐dicyano‐4‐hydroxy‐2,5,6‐trichlorobenzene (compound 2), and l‐carbamoyl‐3‐cyano‐4‐hydroxy‐2,5,6‐trichlorobenzene (compound 3). Compounds 1 and 2 were the major metabolites in soil. In the harvested broccoli (in the flower) and Chinese cabbages (the leaves), the concentrations of chlorothalonil and of compounds 1 and 2 were lower respectively than 0.1, 0.1 and 0.5mg/kg fresh weight.     

Flanders’ urbanity — an outline

This article deals with Flanders’ urbanity. At the moment Flanders, a part of Belgium, is responsible for its own town and country planning. Nevertheless, today's picture of urbanity is, for the greatest part, the result of Belgian policy. The results are nothing to be proud of. In fact Flanders has no urbanity anymore, nor a real rurality. Everywhere in the countryside there are houses and other constructions; on the other hand and consequently the centres of cities and villages are in decay. The following text tries to draw, very briefly, the problems and the development of the problems in urban and rural Flanders. The roots have to be searched in the 19th century, especially in the constitution of Belgium, which is one of the most liberal on earth. The first part of the article is dealing with the history of urbanisation, whilst the second part deals with some recent evolutions in housing and housing policy, in employment and employment policy, in transport and transport policy. Finally, the third part is concerned with the town and country planning which has to structure the developments in spatial use for housing, industrial building and so on, but which has failed.     

Glutathione S-tranferases and cytochrome P450 activities in Mytilus galloprovincialis from the South coast of Portugal: effect of abiotic factors

To assess the health of aquatic organisms, biomarkers that measure changes at the biochemical level have been used as effective early warning tools in ecological risk assessment. In order to develop an integrated risk assessment strategy for the south coast of Portugal, mussels Mytilus galloprovincialis were collected from six sites along the coast with different organic contaminant characteristics. Additionally, an active biomonitoring approach was followed by transplanting indigenous mussels from site 4 to 6 and vice versa (from site 6 to 4) for 28 days. PAHs and PCBs contents were measured and the associated responses of phase I and phase II detoxification mechanisms evaluated by measuring cytochrome P450 and GST activities. GST activity was also determined on different tissues (gills, digestive gland, foot, mantle and gonads) of M. galloprovincialis and the impact of abiotic parameters (temperature, salinity, pH, conductivity and dissolved oxygen) on the GST activity assessed. Results indicate that CYP 450 follow the same pattern of PAHs and a direct relationship exist between CYP 450 and PAH levels from the different sites. Although there is a decrease between GST and PAHs concentrations it was not significant. The majority of the GST activity was in the gills and the digestive gland (around of 75% of the activity measured in all tissues) followed in decreasing order by the mantle, gonads. An inverse relationship between GST activity and salinity was detected along with temperature although not significant. These two biomarkers respond to changes of these two groups of compounds and to salinity especially for GST. In conclusion CYP 450 in mussels gives a reliable response as biomarker for organic contaminants in risk assessment in the South Coast of Portugal.     

Roadside vehicle particulate matter concentration estimation using artificial neural network model in Addis Ababa, Ethiopia

Currently, vehicle-related particulate matter is the main determinant air pollution in the urban environment. This study was designed to investigate the level of fine (PM_2.5) and coarse particle (PM₁₀) concentration of roadside vehicles in Addis Ababa, the capital city of Ethiopia using artificial neural network model. To train, test and validate the model, the traffic volume, weather data and particulate matter concentrations were collected from 15 different sites in the city. The experimental results showed that the city average 24-hr PM_2.5 concentration is 13%–144% and 58%–241% higher than air quality index (AQI) and world health organization (WHO) standards, respectively. The PM₁₀ results also exceeded the AQI (54%–65%) and WHO (8%–395%) standards. The model runs using the Levenberg-Marquardt (Trainlm) and the Scaled Conjugate Gradient (Trainscg) and comparison were performed, to identify the minimum fractional error between the observed and the predicted value. The two models were determined using the correlation coefficient and other statistical parameters. The Trainscg model, the average concentration of PM_2.5 and PM₁₀ exhaust emission correlation coefficient were predicted to be (R² = 0.775) and (R² = 0.92), respectively. The Trainlm model has also well predicted the exhaust emission of PM_2.5 (R² = 0.943) and PM₁₀ (R² = 0.959). The overall results showed that a better correlation coefficient obtained in the Trainlm model, could be considered as optional methods to predict transport-related particulate matter concentration emission using traffic volume and weather data for Ethiopia cities and other countries that have similar geographical and development settings.     

Quantification of carbamazepine and atrazine and screening of suspect organic contaminants in surface and drinking waters

A new approach for the identification of suspect trace organic contaminants in drinking and surface waters is presented. Samples were initially analyzed using a target determination method for two contamination tracers, carbamazepine (CBZ) and atrazine (ATZ). This method used offline solid-phase extraction and online solid-phase extraction techniques coupled to liquid chromatography-triple quadrupole mass spectrometry to accelerate the sample preparation process and improve method performance. CBZ and ATZ were found respectively in 31% and 56% of the samples, and concentrations were usually <20 ng L⁻¹. These samples were re-analyzed with a similar method on a quadrupole time-of-flight mass spectrometer to identify suspect contaminants by means of exact mass measurements and isotope patterns. A database of 264 common organic contaminants was built and used in conjunction with a Molecular Feature algorithm to identify the presence of these substances in drinking and surface water collected from different sources at various locations across Canada. Several organic contaminants were identified in the samples, but only the presence of caffeine, desethylatrazine, simazine and venlafaxine could be verified by comparison to pure standards. The presence of desethylatrazine was also confirmed by MS/MS experiments. These results suggest that target analysis for tracers of organic contamination may be a helpful tool to prioritize samples which should be further screened for suspect contaminants. This study also shows that the combination of separation techniques (offline and online SPE, LC) contribute to advance the applicability of high-resolution mass spectrometry for the identification of trace organic contaminants by accelerating the preparation step, reducing complexity and increasing analyte concentrations for optimal detection.     

Technical and environmental long-term properties of industrial residues--summary of field and laboratory investigations

In Sweden, use of industrial residues is still hindered by concern for their long-term properties. A three-year research project was therefore initiated aiming to (1) identify the crucial processes of ageing related to the usefulness of residues in roads; (2) investigate the consequences of these processes for technical and environmental properties of the residues, and (3) propose a method for accelerated ageing to predict the long-term properties. This paper gives an overview of the project methodology, a summary of the test results and references to papers where further details are given.The project, running through 2006-2008, compared naturally aged samples of two residues used as sub-bases in existing asphalt paved roads with samples of fresh residues from producers’ piles. Steel slag of electric arc furnace (EAF) type and municipal solid waste incinerator (MSWI) bottom ash were chosen. The samples were thoroughly characterised in order to identify which ageing processes had been crucial.The results showed that:

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Bottom ash from the pavement edge was more aged than bottom ash from the road centre. However, no difference in pH was found, instead the differences were caused by differences in water exposure.

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Steel slag from the pavement edge showed traces of carbonation and leaching processes, whereas slag from the road centre was identical to fresh slag.

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Water exposure to the subbase materials after ten years in an asphalt paved road was calculated to less than 0.1-0.5 litres per kg.

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Ageing reactions in steel slag and MSWI bottom ash, ready for use, were too small to be verified by laboratory measurement of deformation properties under loaded conditions.

An accelerated ageing test for steel slag was set up to achieve the carbonation (decrease in pH) and leaching that was observed in the pavement edge material.An accelerated ageing test for bottom ash was set up to achieve the pozzolan reactions that were observed in SEM analyses of in situ specimens.It is recommended to use uncrushed particles when properties of aged material are studied, in order to preserve the original particle surfaces.     

Sustainable decisions on the agenda – a decision support tool and its application on climate-change adaptation

A decision support tool aiming to facilitate discussion and transparency in land-use planning processes has been developed. It includes process steps initiating with an analysis of the current situation, identification of relevant actions and sustainability analysis steps. The sustainability was subdivided into human health and environment, resources, and social and economic impacts. The main difference between this risk analysis tool and others is the allowance of comparisons of present risks and consequences of measures early in the process. It also includes assessments from short- and long-term perspectives, such as taking into account climate change. It combines classic risk analysis with life-cycle assessment procedure. It has been developed and tested in co-operation with municipalities. The tests show that the tool is applicable and can be relevant in the planning process. It offers an iterative discussion framework that is systematic, condensed and yet a simplistic way of describing consequences. The criticism is that it is regarded as time demanding, but this can be managed by preparatory work.