Chlorophenols in river sediment in The Netherlands

In this paper an analytical method is described for the capillary gas chromatographic determination, after derivitization, of 19 individual chlorophenols in river sediment. The minimum detectable amounts are for monochlorophenols 10 μg kg⁻¹, dichlorophenols 0.5 μg kg⁻¹, trichlorophenols 0.2 μg kg⁻¹ and for tetra- and pentachlorophenols 0.1 μg kg⁻¹. The results of a monitoring program in the Rhine River and its tributaries and other Dutch surface waters with respect to these compounds are presented. 2,5-Dichlorophenol, 2,3,5- and 2,4,5-trichlorophenol, 2,3,4,5- and 2,3,4,6-tetrachlorophenol and pentachlorophenol had a frequency of occurrence of 100% in sediment samples from Lake Ketelmeer, which is a deposition area for Rhine River sediment. The highest concentrations of chlorophenols were found in the Nieuwe Maas River near Rotterdam, a heavily industrialized area.     

Lipophilic organic contaminants in the Rhine river, Germany

Detailed gas chromatographic-mass spectrometric analyses applied to eight Rhine river water samples constituted a comprehensive characterization of the low molecular weight organic contamination. Within the group of predominant anthropogenic contaminants, only a few compounds were characterized as frequently detected or priority pollutants. Numerous compounds exhibiting physiological or ecotoxicological properties are only rarely reported or still unnoticed riverine contaminants. Information on environmental behaviour or ecotoxicological effects is still limited for most of these substances. In particular, several brominated compounds (mono- and dibrominated (methoxyphenyl)propionic acids and hydroxymethylacetophenones) were identified for the first time as environmental contaminants. Quantitative analyses differentiated five groups of pollutants with respect to their concentration profiles. The spatial distribution and the intensity of emission sources on the one hand and the environmental stability as well as the tendency to adsorb on the particulate matter on the other hand determined the quantitative occurrence of individual compounds.     

Mutagenic activity in the rivers Rhine and Meuse in The Netherlands

Several water samples of the rivers Rhine and Meuse have been tested for mutagenic activity in the Ames Salmonella/microsome assay and a fluctuation assay. Samples were taken at places where the rivers enter The Netherlands and at several downstream locations relevant to drinking water supplies. For the Rhine this included samples of each of the river-branches Waal, Lek and IJssel. Before testing, all water samples were concentrated by adsorption on XAD-resins and subsequent elution with dimethylsulfoxide.The results obtained clearly show that all water samples derived from the river Rhine and its branches contain mutagenic activity. Positive Ames test results showing dose—response relations were observed primarily with strain TA 98 after metabolic activation (rat liver microsomal enzymes). In contrast to this, little or no mutagenic activity was detected in samples from the river Meuse. This indicated that, with the methods used, the overall mutagenic activity of the river Meuse was at least 10 times below that of the river Rhine. In the fluctuation assay, using the same bacterial strains, the river water concentrates could not be tested as such. However, after appropriate dilution of the dimethylsulfoxide with distilled water, this assay proved to be about 10–15 times more sensitive than the Ames test. The significance of these results with respect to human health is briefly discussed.     

Geo-referenced modeling of zinc concentrations in the Ruhr river basin (Germany) using the model GREAT-ER

Zinc enters surface waters from a variety of different emission sources. The geo-referenced model GREAT-ER (Geo-referenced Regional Exposure Assessment Tool for European Rivers) was applied to simulate spatially resolved zinc concentrations in the Ruhr river basin. The model links geo-referenced emissions (loads) to concentrations at local and regional scales and allows for evaluating the relative importance of emission sources. For each emission from point sources (household, industry, urban runoff) and non-point sources (agriculture, natural background), zinc loads were independently estimated using appropriate reference parameters (number of inhabitants, surface area drained, agricultural area, zinc ore regions). For point emissions from industry and mine drainage loads were taken directly from available data compilations. Simulated total zinc concentrations agree well with monitoring data. The strength of the modeling tool became evident from the unequivocal link that could be established between observed surface water concentrations and the large zinc input from geogenic sources and abandoned mines. These emission sources are regional characteristics of the Ruhr river basin and due to the fact that some regions are relatively rich in zinc ore, which was extracted over a long period of time. Although most of these emissions occur in the upper part of the catchment, they contribute to approximately one-third to the zinc load at the confluence with the Rhine River. Urban emissions from household, traffic (road) and buildings (roof) were shown to be responsible for approximately half of the concentration in the Ruhr at the confluence with the Rhine River.     

Managing a complex river catchment: a case study on the River Almond

The River Almond catchment in the east central belt rates amongst Scotland's most polluted rivers. This paper describes how shifting forms of economic development in the catchment since the 1860s have affected river quality. A legacy of effects from past land uses has combined with the impacts associated with current land uses to present a substantial and complex management challenge. It is argued that there have been, and still are, scientific, legislative and socio-economic constraints on the abilities of managers to respond promptly to changing patterns of impacts on the river system. This response lag has tended to increase the costs of subsequent remediation, and has consequently supported a downward pressure on the quality standards that are considered 'realistic' by river managers. Conversely, advances in science, the expansion of regulatory powers and resources, and an increase in public interest in the environment has helped to clarify the extent of the management problems in the catchment, and allowed major advances in some areas of pollution management. In an attempt to overcome some of the remaining weaknesses of river management, river managers and interest groups have started to form inter-sectoral and multidisciplinary partnerships. The success of these new groupings is highly contingent, not so much on the competence of their scientific advice, but on the priority given to water protection by the land-use decision-makers involved, and the resources they are prepared to commit to funding rehabilitation.     

Pollution of the river rhine with halogenated organic compounds an investigation during a “Fliessende Welle”

In August 1982 and between 13 September–1 October 1982, during two “Fliessende Welle” surveys, about 400 R. Rhine water sample were taken. The total organic halogen contents of about 200 samples were analyzed by different methods. In waste water samples, as well as in river water samples, there were considerable differences in the analytical data depending on the method used. Some discharge points for organic halogens into the Rhine are identified.     

The occurrence and role of Bdellovibrio bacteriovorus in a polluted river

Bdellovibrio bacteriovorus was found to occur in a polluted river in numbers averaging, over an 18 month period, 10–100 parasites/ml. The parasite was not able to grow at river temperatures on host concentrations below about 10⁶–10⁷ bacteria per ml and even at these had a doubling time of only 24–48 h. The results have indicated that the parasite was not important in reducing the bacterial population of the river studied.     

A bacterial methylmercury-mineralizing activity in river sediments

A bacterial activity involving mineralization of methylmercury was found in bottom sediments of the river Sambre (Belgium), in a zone highly polluted with inorganic mercury. The possibility, shown by other authors and ourselves, that biological production of toxic methylmercury compounds occurs in such a medium gives a great ecological significance to this finding.Some properties of this mineralizing activity were studied at the community level in the laboratory.The mineralizing capacity of the community can be increased in response to increased concentrations of methylmercury, probably by means of the selection of methylmercury-resistant bacterial species, among which the organisms responsible for the transformation constitute only a part.Because of this adaptation, it is suggested that some equilibrium can be reached between the degradation of methylmercury and its addition to, or its production in, mineral mercury polluted environments.     

The microcoulometric determination of extractable organic halogen in surface water; Application to surface waters of The Netherlands

In this paper an analytical method is described for the microcoulometric determination of extractable organic halogen, especially chlorine, in surface waters and sediments. The minimum detectable amounts of chlorine are respectivelly 1.0 μg/l (ppb) in water and 0.5 mg/kg (ppm) in sediments. The results of a monitoring program in the river Rhine and several Dutch surface waters with respect to this parameter are presented. The results cover the period January 1973 to December 1975.In 1973, 1974 and 1975 the average daily loads of organic halogen calculated as chlorine in the river Rhine at Lobith were 3300, 3410 and 2050 kg, respectively.The parameter “Extractable Organic Chlorine” (EOCl) is suggested as a useful general indicator for chemical pollution in surface waters and in effluents from industrial plants.     

Analysis of photosynthetic activity in the most polluted stretch of river Ganga

As a result of the increasing anthropogenic activities in the gangetic plain, Ganga water quantity as well as quality has declined over the years. A major effort to clean Ganga, named Ganga Action Plan (GAP) was instituted by the Government of India in 1984. The emphasis in GAP was on the reduction of organic load on the river through interception, diversion and treatment of wastewater reaching the river, thus maintaining the biochemical oxygen demand (BOD) and dissolved oxygen (DO) levels of river within the acceptable limits. A major criticism of GAP is that the significance of river ecology has not been addressed adequately during its conception and implementation. One of the important aspects from this perspective is the photosynthetic activity in the river Ganga. It has been postulated that photosynthetic activity plays an important role in maintaining high levels of DO in Ganga, and as a result the river can assimilate high organic loads without appreciable depletion in dissolved oxygen levels. Objective of the present study was to assess the photosynthetic activity and oxygen production rates in the river and correlate these values with various water quality parameters. Most polluted stretch of Ganga, which is known as the Kannauj-Kanpur stretch was chosen for this study. Based on the results of the study, it was concluded that despite implementation of phase I of GAP, and consequent diversion and reduction of organic loading to the river, both BOD and DO levels in the river has increased in the entire Kannauj-Kanpur stretch, except at Jajmau, where anaerobically treated effluent is discharged to the river. The nitrogen levels have also increased in the entire Kannauj-Kanpur stretch. Dissolved oxygen (DO) and alkalinity in the river water vary diurnally at all sites. Chlorophyll-a levels and oxygen production rates due to photosynthesis appear to be positively influenced by phosphate levels in the river water. Chlorophyll-a levels appear to be negatively correlated to the Ammonical and total Total Kjeldahl Nitrogen (TKN) content in the river water, suggesting the possibility of release of nutrients due to algal death and decomposition under certain circumstances.     

Algal diversity in relation to water quality in an Indian river

The application of the two diversity indices (Shannon's index of diversity and Margalef s index of diversity) has been critically analysed for water pollution monitoring in the tropical polluted river Khan. These two indices can be usefully employed for the biological assessment of water quality in tropical polluted rivers.     

Geochemistry of suspended particulate matter in two natural sedimentation basins of the river Rhine

Multivariate analysis procedures have been used to trace possible correlations between changes in the composition of particulate organics and changes in the ratios of trace metal contents of suspended matter present in two major sedimentation basins of the river Rhine. In both basins, seaward gradients are observed in the organic characteristics as well as in the trace metal “patterns”. These two phenomena are well correlated. For both basins the changes in the two types of characteristics can be explained by simultaneously operating processes of sedimentation, autochthonous production and sediment resuspension.     

河畔漫步——莱茵河畔步道景观设计

该项目涵盖了路德维希港及城市规划中整个莱茵河的景观设计,旨在向人们展示整个莱茵河畔的风貌。随着城市和莱茵河的联系日益紧密,该项目中的雕塑及其他的设计亮点都更加注重体现城市与莱茵河的联系,而为市民开放的公共空间也在不断的完善中,使其更具吸引力。     

Determination of organochlorines in river sediment by capillary gas chromatography: Application to Dutch river sediment

An analytical method is described for the capillary gas chromatographic determination of 17 organochlorines, such as HCB, α-, β- and γ-HCH, aldrin, dieldrin, endrin, isodrin, telodrin, C-601 (1,2,3,4,7,7-hexachlorobicyclo-[2,2,1]-heptadieen-2,5), C-773 (1,2,3,4,5,7,7-heptachlorobicyclo-[2,2,1]-hepteen-2), heptachlor, β-heptachlorepoxide and the DDT-complex, in soil and river sediment. C-601 and C-773 are by-products of the aldrin and dieldrin synthesis. Several solvents were compared for the extraction from clay, peat and river sediment. Acetone gave the best results, also after a long period between spiking of soil and sediment samples with organochlorines and extraction. 14 Organochlorines were determined without interference from PCBs. The analysis of heptachlor, aldrin and p·p′-DDT can be interfered with by PCB components.The results of a monitoring program in tributaries of the Rhine River, Western Scheldt and in some harbour basins of Rotterdam are presented. HCB occurred frequently. The most contaminated sediment was found in a harbour basin near a pesticide producing plant. In this sediment the mean concentrations were 0.86 mg kg⁻¹ and 0.18 mg kg⁻¹ for dieldrin and endrin, respectively, on a dry weight basis.     

Do the VOCs that evaporate from a heavily polluted river threaten the health of riparian residents?

To understand the potential threat of volatile organic compounds (VOCs) to the health of residents living close to a heavily polluted river, this study investigated the species and the concentration of VOCs evaporating from a river and surveyed the health condition of the nearby residents. Air samples were taken seasonally at the upstream, midstream, and downstream water surfaces of the river, and at different locations at certain distances from the river. These samples were analyzed qualitatively and quantitatively through gas chromatography and electron capture detector (GC/ECD) for chlorinated organic compounds, and through gas chromatography and flame ionization detector (GC/FID) for ordinary hydrocarbons. The health data obtained from valid health questionnaires of 908 residents were analyzed through Statistical Package for Social Science (SPSS) software. Twenty-six species of VOCs were identified in the environment adjacent the river, many of which are carcinogenic or believed to be carcinogenic to humans. However, results of this study shows that the VOCs evaporating from the polluted river have not been definitively identified as a major factor of cancer in the residents. However, the risk of suffering from certain chronic diseases may increase in residents living less than 225 m away from the river due to the high levels of evaporated VOCs. Residents living less than 225 m away from the river and with nearby specific industries are 3.130 times more at risk of suffering from chronic diseases than those with no nearby specific industries.     

黄河流域水污染分析及保护措施

对黄河流域水资源污染及其污水排放现状进行了介绍,在此基础上,分析了黄河流域废污水排放情况、水质污染程度、污染物的组成等情况,并提出水资源的保护措施。     

Organic matter transport and degradation in the river Seine (France) after a combined sewer overflow

The impact of a combined sewer overflow (CSO) upon receiving waters has been studied in the river Seine during Summers 1995 and 1996. Three main events have been monitored with special attention paid to the computation of oxygen, carbon and suspended solids budgets. Bacterial biomass and bacterial production rates have been measured to provide a more accurate understanding of the carbon cycle of the river Seine. Oxygen consumption inside the polluted water masses was totally due to the activity of large bacteria discharged into the river by the CSO, the activity of native small bacteria did not significantly increase after CSOs. Suspended solids issued from the CSO very quickly settles in this deep, slowly flowing river. However, discharged dissolved organic carbon (DOC) cannot account for the observed oxygen depletions, the additional carbon source could be phytoplankton or deflocculated/degraded particulate organic matter.     

Time series analysis on ammonia concentration and load values of the river Rhine

The autocorrelation technique is applied to ammonia data observed in the river Rhine and is used for two purposes. On one hand the error in the determination of the NH₄⁺-concentration, caused by both analysing and sampling errors, can be quantified. On the other hand the behaviour of the NH₄⁺-concentration and NH₄⁺-load is described. It is indicated that the NH₄⁺-load is a stochastic variable containing a periodicity, whereas the NH₄⁺-concentration is a merely stochastic variable with a large time constant.     

Children's perceptions of river landscapes and play: what children's photographs reveal

The insights that children's photography can provide into children's perceptions of river landscapes and play opportunities are focused upon, based on an analysis of over 500 photographs and comments generated during visits to two London rivers by children aged nine to eleven from three nearby schools. In their photographs, the children recognized the aesthetic appeal of specific natural features of the river landscapes, particularly trees. Some also appreciated broader river landscape 'views'. The rivers themselves were seen as littered and polluted. Dangers were identified, but these were not seen as unmanageable. The children recognized the special character of the rivers as play places affording varied, adventurous and manipulable play opportunities, but wanted cleaner, safer, more accessible and managed rivers. Some differences were found in the responses of boys and girls and in the children's responses to the two rivers. The urban children taking part in the study showed little understanding of the functions that living and decaying riverside vegetation might have in river ecology, indicating a need for more environmental education.     

Quality of dredged material in the river Seine basin (France). II. Micropollutants

Dredging rivers is needed to ensure safe navigable waters, rivers and waterways. To anticipate the management of dredged materials in the case of the river Seine basin, the quality of the sediments in the river is checked every 3 years before dredging operations. The river Seine Basin is heavily submitted to pollution pressure from nearby industrial activities and urban expansion of Paris and its region. Here, the micropollutant content of the sediment sampled in 1996, 1999 and 2000 before dredging is discussed compared to regulatory standards. The results indicate that most of the sediment samples from the river Seine basin are lightly to moderately contaminated with organic and inorganic micropollutants (heavy metals, PAH, PCB), which makes the management after dredging easier. This pollution is strongly correlated with the organic matter content and to the fine fraction (<50 microm) of the sediment. These results can lead to other management options than the ones already used in the river Seine basin: (1) dumping of lightly to moderately polluted sediments in quarries; and (2) physical treatment (sieving, hydrocycloning) of contaminated sediments issued from 'hot spots'.