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1.
Wastewater treatment plants (WWTPs) are commonly considered as the main source of pharmaceuticals in surface waters. Here, however, we show that an open-air festival, attracting approximately 10,000 visitors per year at the shores of River Fyris upstream of Uppsala WWTP, can temporarily result in a higher pharmaceutical input into the river water than the WWTP. Studying the influence of Uppsala Reggae festival on the occurrence of ten commonly used acidic and basic pharmaceuticals upstream, in the effluent, and downstream of the Uppsala WWTP, we found that occasional heavy rainfalls during the festival in 2008 severely increased the mass flows of all pharmaceuticals at the WWTP upstream site. Also, strong increases in ammonium (210-fold), nitrate (21-fold), and total nitrogen (21-fold) mass flows were observed. The pharmaceutical mass flows at the upstream site were up to 3.4 times higher than those observed in the WWTP effluent. In contrast, in 2009, the festival was not accompanied with rainfalls and no major additional input of pharmaceuticals and nitrogen was observed. The findings of this study give new insights into risk assessments and are relevant for monitoring programmes.  相似文献   

2.
The existence of pharmaceuticals in the water environment is thought to be a potential problem for aquatic organisms. In this study, we conducted a nationwide survey to clarify the occurrence of 24 selected pharmaceuticals in major Japanese rivers and evaluated their environmental risk to aquatic organisms. We found a total of 22 substances in river waters at concentrations from several nanograms per liter to several micrograms per liter. We found the highest, which was 2.4 μg/L of caffeine, followed by 1.5 μg/L of crotamiton and 1.4 μg/L of sulpiride. We conducted an environmental risk assessment of the 22 pharmaceuticals detected in river water, for which predicted no-effect concentration (PNEC) values for crustacea and algae had been obtained. The measured environmental concentration/PNEC values of four substances, caffeine, carbamazepine, clarithromycin, and ketoprofen, exceeded 0.1 with the maximum value of 9.0 for clarithromycin. As clarithromycin exhibits a high environmental risk to aquatic organisms, particular attention is required.  相似文献   

3.
Sediment oxygen demand (SOD) has become an integral part of modeling dissolved oxygen (DO) within surface water bodies. Because very few data on SOD are available, it is common for modeler to take SOD values from literature for use within DO models. SOD is such an important parameter in modeling DO that this approach may lead to erroneous results. This paper reported on developing an approach for monitoring sediment oxygen demand conducted with undisturbed sediment core samples, where the measured results were incorporated into a water quality model for simulating and assessing dissolved oxygen distribution in the Xindian River of northern Taiwan. The measured results indicate that a higher freshwater discharge results in a lower SOD. Throughout a 1-year observation in 2004, the measured SOD ranged from 0.367 to 1.246 g/m(2)/day at the temperature of 20°C. The mean values of the measured SOD at each station were adopted in a vertical two-dimensional water quality model to simulate the DO distribution along the Xindian River. The simulating results accurately depict the field-measured DO distribution during the low and high flow conditions. Model sensitivity analyses were also conducted with increasing and decreasing SOD values for the low and high flow conditions and revealed that SOD had a significant impact on the DO distribution along the Xindian River. The present work combined with field measurements and numerical simulation should assist in river water quality management.  相似文献   

4.
A dissolved oxygen (DO) model is calibrated and verified for a highly polluted River Ravi with large flow variations. The model calibration is done under medium flow conditions (431.5 m3/s), whereas the model verification is done using the data collected during low flow conditions (52.6 m3/s). Biokinetic rate coefficients for carbonaceous biochemical oxygen demand (CBOD) and nitrogenous biochemical oxygen demand (NBOD) (i.e, K cr and K n ) are determined through the measured CBOD and ammonia river profiles. The calculated values of K cr and K n are 0.36 day?1 and 0.34 day?1, respectively. The close agreement between the DO model results and the field values shows that the verified model can be used to develop DO management strategies for the River Ravi. The biokinetic coefficients are known to vary with degree of treatment (DOT) and therefore need to be adjusted for a rational water quality management model. The effect of this variation on level of treatment has been evaluated by using the verified model to attain a DO standard of 4 mg/L in the river using the biokinetic rate coefficients as determined during the model calibration and verification process. The required DOT in this case is found to be 96 %, whereas the DOT is 86 % if adjusted biokinetic rate coefficients are used to reflect the effect of wastewater treatment. The cost of wastewater treatment is known to increase exponentially as the removal efficiency increases; therefore, the use of appropriate biokinetic coefficients to manage the water quality in rivers is important.  相似文献   

5.
Dynamics of heavy metals such as Fe, Mn, Zn, Cr, Cu, Co, Ni, Pb, and Cd in surface water of Mahanadi River estuarine systems were studied taking 31 different stations and three different seasons. This study demonstrates that the elemental concentrations are extremely variable and most of them are higher than the World river average. Among the heavy metals, iron is present at highest concentration while cadmium is at the least. The spatial pattern of heavy metals suggests that their anthropogenic sources are possibly from two major fertilizer plants and municipal sewage from three major towns as well as agricultural runoff. The temporal variations for metals like Fe, Cu, and Pb exhibit higher values during the monsoon season, which are related to agricultural runoff. Concentrations of Ni, Pb, and Cd exceed the maximum permissible limits of surface water quality in some polluted stations and pose health risks. Dissolved heavy metals like Fe, Mn, Cr, Ni, and Pb exhibit a non-conservative behavior during estuarine mixing, while Zn, Cu, and Co distribution is conservative. Distribution of cadmium in the estuarine region indicates some mobilization which may be due to desorption. The enrichment ratio data suggest that various industrial wastes and municipal wastes contribute most of the dissolved metals in the Mahanadi River. The Mahanadi River transports 18.216 × 103 t of total heavy metals into the Bay of Bengal and the calculated rate of erosion in the basin is 128.645 kg km − 2 year − 1.  相似文献   

6.
The mass flows of selected pharmaceuticals and personal care products (PPCPs) were studied in the aqueous compartment of the river Somes in Romania. PPCPs were measured in wastewater treatment effluents and in the receiving river water. The analytical method for the determination of PPCPs in river water was based on solid phase extraction and GC-ITMS. Carbamazepine, pentoxyfylline, ibuprofen, diazepam, galaxolide, tonalide and triclosan were determined in wastewater effluents with individual concentrations ranging from 15 to 774 ng L(-1). Caffeine was measured at concentrations up to 42 560 ng L(-1). Due to the high contamination of WWTP effluents, the receiving river was also polluted. The most abundant PPCPs measured in the Somes were caffeine, galaxolide, carbamazepine and triclosan. They were present at all the 15 sampling sites along the Somes, the concentrations ranging from 10 to 400 ng L(-1). The concentrations in the effluents of the different wastewater treatment plants (WWTPs) varied considerably and the differences are due to different elimination efficiencies of the studied PPCPs during sewage treatment. Only one of 5 WWTPs studied, the WWTP in Cluj-Napoca, was working properly, and therefore technical measures have to be taken for upgrading the WWTPs and reducing the environmental load of micropollutants. This study is the first overview of PPCPs along on Romanian part of river Somes.  相似文献   

7.
The southwestern coast of India is drained by many small rivers with lengths less than 250 km and catchment areas less than 6,500 km2. These rivers are perennial and are also the major drinking water sources in the region. But, the fast pace of urbanization, industrialization, fertilizer intensive agricultural activities and rise in pilgrim tourism in the past four to five decades have imposed marked changes in water quality and solute fluxes of many of these rivers. The problems have aggravated further due to leaching of ionic constituents from the organic-rich (peaty) impervious sub-surface layers that are exposed due to channel incision resulting from indiscriminate instream mining for construction-grade sand and gravel. In this context, an attempt has been made here to evaluate the water quality and the net nutrient flux of one of the important rivers in the southwestern coast of India, the Manimala river which has a length of about 90 km and catchment area of 847 km2. The river exhibits seasonal variation in most of the water quality parameters (pH, electrical conductivity, dissolved oxygen, total dissolved solids, Ca, Mg, Na, K, Fe, HCO3, NO2-N, NO3-N, P \text-inorg_{\rm \text{-}inorg}, P \text-tot_{\rm \text{-}tot}, chloride, SO4, and SiO2). Except for NO3-N and SiO2, all the other parameters are generally enriched in non-monsoon (December–May) samples than that of monsoon (June–November). The flux estimation reveals that the Manimala river transports an amount of 2,308 t y − 1 of dissolved inorganic nitrogen, 87 t y − 1 dissolved inorganic phosphorus, and 9246 t y − 1 of SO4, and 1984 t y − 1 K into the receiving coastal waters. These together constitute about 23% of the total dissolved fluxes transported by the Manimala river. Based on the study, a set of mitigation measures are also suggested to improve the overall water quality of small catchment rivers of the densely populated tropics in general and the south western coast in particular.  相似文献   

8.
A stream water quality model, QUAL2Kw, was calibrated and validated for the river Bagmati of Nepal. The model represented the field data quite well with some exceptions. The influences of various water quality management strategies have on DO concentrations were examined considering: (i) pollution loads modification; (ii) flow augmentation; (iii) local oxygenation. The study showed the local oxygenation is effective in raising DO levels. The combination of wastewater modification, flow augmentation and local oxygenation is necessary to ensure minimum DO concentrations. This reasonable modeling guarantees the use of QUAL2Kw for future river water quality policy options.  相似文献   

9.
10.
In order to obtain representative dissolved and solid samples from the aquatic environment, a spectrum of sampling methods are available, each one with different advantages and drawbacks. This article evaluates the use of discrete sampling and time-integrated sampling in illustrating medium-term spatial and temporal variation. Discrete concentration index (CI) calculated as the ratio between dissolved and solid metal concentrations in grab samples are compared with time-integrated concentration index (CI) calculated from suspended particulate matter (SPM) collected in sediment traps and labile metals measured by the diffusive gel in thin films (DGT) method, collected once a month during one year at the Seine River, upstream and downstream of the Greater Paris Region. Discrete CI at Bougival was found to be significantly higher than at Triel for Co, Cu, Mn, Ni and Zn, while discrete metal partitioning at Marnay was found to be similar to Bougival and Triel. However, when using time-integrated CI, not only was Bougival CI significantly higher than Triel CI, CI at Marnay was also found to be significantly higher than CI at Triel which was not observed for discrete CI values. Since values are time-averaged, dramatic fluctuations were smoothed out and significant medium-term trends were enhanced. As a result, time-integrated concentration index (CI) was able to better illustrate urbanization impact between sites when compared to discrete CI. The impact of significant seasonal phenomenon such as winter flood, low flow and redox cycles was also, to a certain extent, visible in time-integrated CI values at the upstream site. The use of time-integrated concentration index may be useful for medium- to long-term metal studies in the aquatic environment.  相似文献   

11.
Rapid urban development has led to a critical negative impact on water bodies flowing in and around urban areas. In the present study, 25 physiochemical and biological parameters have been studied on water samples collected from the entire section of a small river originating and ending within an urban area. This study envisaged to assess the water quality status of river body and explore probable sources of pollution in the river. Weighted arithmetic water quality index (WQI) was employed to evaluate the water quality status of the river. Multivariate statistical techniques namely cluster analysis (CA) and principal component analysis (PCA) were applied to differentiate the sources of variation in water quality and to determine the cause of pollution in the river. WQI values indicated high pollution levels in the studied water body, rendering it unsuitable for any practical purpose. Cluster analysis results showed that the river samples can be divided into four groups. Use of PCA identified four important factors describing the types of pollution in the river, namely (1) mineral and nutrient pollution, (2) heavy metal pollution, (3) organic pollution, and (4) fecal contamination. The deteriorating water quality of the river was demonstrated to originate from wide sources of anthropogenic activities, especially municipal sewage discharge from unplanned housing areas, wastewater discharge from small industrial units, livestock activities, and indiscriminate dumping of solid wastes in the river. Thus, the present study effectively demonstrates the use of WQI and multivariate statistical techniques for gaining simpler and meaningful information about the water quality of a lotic water body as well as to identify of the pollution sources.  相似文献   

12.
This research compared the structural and chemical characteristics among dissolved organic matter (DOM) fractions within the same source and among different origins. Samples taken from the Taiping Wastewater Treatment Plant (TWTP) (Harbin, China) and from the Songhuajing River (SR), Heilongjiang Province, China were chosen to represent waters containing DOM of wastewater origin and of natural-water origin, respectively. DOM was fractionated using XAD resins into five fractions: hydrophobic acid (HPO-A), hydrophobic neutral (HPO-N), transphilic acid (TPI-A), transphilic neutral (TPI-N) and hydrophilic fraction (HPI). The SR fractions were more UV-sensitive and more reactive with chlorine in formation of trihalomethanes (THMs) than the TWTP secondary effluent (TSE) fractions. The aromatic character peaks in the Fourier-transform infrared (FT-IR) spectra of SR fractions were clearer than those of TSE fractions. On the other hand, the peaks of carbohydrates in TSE fractions were more prominent in comparison with SR fractions. In addition, the amide-2 peak was present in the spectra of all the five TSE fractions but not visible in the spectra of SR fractions. The fluorescence results showed that SR DOM fractions contained more fulvic acid-like fluorescent compounds while TSE DOM fractions had higher amounts of protein-like fluorescent components.  相似文献   

13.
The mutagenic activity of XAD-2 adsorbates and water extracts recovered from nine locations of the Kumho River was tested on S. typhimurium TA98 strain to identify the source of the mutagenicity. A sampling site, receiving effluents from the textile industrial complex located in Daegu City, showed extraordinarily high mutagenic activity, especially in the presence of S9 mixture, at all sampling time in both XAD-2 adsorbates and dichloromethane extracts. This indicated the existence of the frame-shift mutagens in the Kumho River, same type of mutagens detected in previous studies by other researchers in the Nakdong River into which the Kumho River discharges. The fractionation study showed that the mutagenic chemicals in the river water are mid-polar. Furthermore, mean tail length obtained by single cell gel electrophoresis assay (Comet assay) showed consistent dose-dependent DNA damage, indicating that the chemicals in the river water not only act as frame-shift mutagens but also break human lymphocytes DNA strain. Chemical identification of the mutagens should be required.  相似文献   

14.
The aim of this study is to investigate the air pollution situation in an urban area in southwestern Luxembourg and to simulate annual NO2 and PM10 concentrations in response to changes in meteorological conditions and emissions using a Gaussian dispersion model. Simulations are carried out for the years 1998–2006. Emission scenarios related to road transport and nonindustrial combustion are performed in order to predict changes of air pollution levels. Road transport is by far the most important local emission source in the study area. Scenarios with more stringent emission standards for vehicles, less traffic, and fewer heavy-duty vehicles lead to reductions of NOx and primary PM10 emissions. As a result, the annual NO2 concentrations are decreasing in most parts of the study area and are below the European annual limit value of 40 μg?m?3. In contrast, a scenario with increased use of wood pellets for domestic heating shows an increase in urban PM10 concentration. The year-to-year variability of meteorological conditions accounts for the same magnitude of absolute NO2 and PM10 concentration changes as the emission scenarios. The comparison with measurements located in the study area shows that the model is able to predict urban-scale annual average air pollution. The proposed application results show that the model can be appropriate for policy-driven air quality management and planning queries.  相似文献   

15.
The occurrence and behavior of β-blockers, antiepileptic drug carbamazepine and its metabolites, X-ray contrast agent iopromide, natural and synthetic hormones, and several groups of hormone-like personal care products (PCPs), including antiseptics (triclocarban, triclosan, and 2-phenylphenol), parabens and bisphenol A, were investigated in municipal wastewater, sewage sludge, and urban river water of the Pearl River Delta, South China. The pharmaceuticals, natural hormones and PCPs were ubiquitously detected in the raw wastewater from a sewage treatment plant (STP). Only triclocarban and triclosan were detected at significant amounts in the dewatered sludge. Iopromide and the PCPs were greatly removed/transformed from the aqueous phase of the wastewater. The β-blockers were only moderately removed/transformed. Carbamazepine passed through the STP almost unchanged. Biodegradation was the dominant process for elimination/transformation of the pharmaceuticals, hormones, and most PCPs in the STP. However, sorption also played an important role in the fate of triclocarban with nearly 50% of the mass load entering the STP ended up and persisted in the dewatered sludge. The pharmaceuticals, estrone, and PCPs were also widely detected in the Pearl River at Guangzhou. Bisphenol A had the highest concentration. The pharmaceutical concentrations in the Pearl River were higher in March than in May, most likely due to less dilution by lower precipitation. The omnipresence and high levels of the pharmaceuticals and PCPs in the Pearl River may be associated with direct discharge of untreated wastewater and pose potential risks to the ecological system.  相似文献   

16.
We estimate the nutrient budget in a temporary Mediterranean river basin. We use field monitoring and modelling tools to estimate nutrient sources and transfer in both high and low flow conditions. Inverse modelling by the help of PHREEQC model validated the hypothesis of a losing stream during the dry period. Soil and Water Assessment Tool model captured the water quality of the basin. The ‘total daily maximum load’ approach is used to estimate the nutrient flux status by flow class, indicating that almost 60 % of the river network fails to meet nitrogen criteria and 50 % phosphate criteria. We recommend that existing well-documented remediation measures such as reforestation of the riparian area or composting of food process biosolids should be implemented to achieve load reduction in close conjunction with social needs.  相似文献   

17.
A single compartment model has been constructed for predicting hourly concentrations of pollutant concentrations arising from vehicular emissions within a typical street canyon. The model takes account of traffic densities and composition to estimate pollutant emissions within the model compartment. Meteorological data on wind speed and direction are used to define the exchanges of pollutants between the compartment and the surrounding air. A parameter is also included to describe the exchange in calm conditions. The pollutant concentrations are then estimated from a steady state mass balance equation for the compartment, assuming conservation of pollutants. The model was applied to the prediction of carbon monoxide concentrations in Hope Street, Glasgow. Model parameters were fitted using field measurements, together with concurrent meteorological data and traffic flows estimated from traffic census data for Hope Street. The model accounted well for the observed variations in carbon monoxide. It was found that the model parameters varied seasonally, perhaps due to differences in atmospheric stability which have not so far been included in the model formulation.  相似文献   

18.
Intra-tidal variability in the transport of materials through the Cochin estuary was studied over successive spring and neap tides to estimate the export fluxes of nutrients and chlorophyll a into the adjoining coastal zone. The results showed that there was a substantial increase in the freshwater flow into the estuary following heavy rains (~126 mm) prior to the spring tide observations. The estuary responded accordingly with a relatively larger export through the Cochin inlet during spring tide over neap tide. Despite an increased freshwater discharge during spring tide, the export fluxes of phosphate and ammonia were high during neap tide due to their input into the estuary through anthropogenic activities. The significance of this study is that the export fluxes from the Cochin estuary could be a major factor sustaining the spectacular monsoon fishery along the southwest coast of India.  相似文献   

19.
Housedusts and garden soils were sampled in 14 houses in the vicinity of a secondary Pb smelter and analysed for concentrations of Pb, Zn, Cu, Cd, As, and Hg. Sixty-one topsoil samples were also taken from a 2 km2 grid covering the smelter grounds and surrounding residential areas and analysed for concentrations of Pb, Zn, Cd and Cu. Contour maps generated from the grid data indicate significant contamination in the area (maximum Pb concentration 58 500 g g-1), particularly down-wind of the smelter grounds. A geometric mean Pb concentration of 2225 g g-1 was recorded in garden soil and similarly elevated levels were recorded for Zn, Cd, As and Sb. In housedusts, a geometric mean Pb concentration of 1668 g g-1 was observed. Whilst housedust metal concentrations were generally elevated, compared to other urban or residential areas, there appears to be a large degree of attenuation of the metals between the exterior and interior environments of the homes studied. A significant correlation was not recorded between metal concentrations of garden soils and housedusts. There were significant correlations for: distance from the smelter against garden soil metal concentrations; garden soil metal concentrations against each other; housedust metal concentrations against each other; and house age against garden soil metal concentrations.  相似文献   

20.
The presence of pharmaceuticals in the environment is now a major concern given their potential adverse effects on organisms, particularly human beings. Because the feeding style and habitat of the crab Carcinus maenas make this species vulnerable to organic contaminants, it has been used previously in ecotoxicological studies. Lysosomal membrane stability (LMS) in crabs is a general indicator of cellular well-being and can be visualized by the neutral red retention (NRR) assay. LMS in crab hemolymph has been evaluated as a cellular biomarker of adverse effects produced by exposure to pharmaceutical compounds. Crabs were exposed in the laboratory to four different pharmaceuticals for 28 days in a semistatic 24-h renewal assay. Filtered seawater was spiked every 2 days with various concentrations (from 0.1 to 50 μg·L?1) of caffeine, ibuprofen, carbamazepine, and novobiocin. Results showed that NRR time, measured at day 28, was significantly reduced (p?<?0.05) after exposure to environmental concentrations of each pharmaceutical (caffeine?=?15 μg·L?1; carbamazepine?=?1 μg·L?1; ibuprofen?=?5 μg·L?1; and novobiocin?=?0.1 μg·L?1) when compared with control organisms. The predicted “no environmental effect” concentration/measured environmental concentration results showed that the selected pharmaceuticals are toxic at environmental concentrations and need further assessment. LMS monitoring in crabs is a sensitive tool for evaluating exposure to concentrations of selected drugs under laboratory conditions and provides a robust tier 1 testing approach (screening biomarker) for rapid assessment of marine pollution and environmental impact assessments for analyzing pharmaceutical contamination in aquatic environments.  相似文献   

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