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1.
Six pharmaceuticals of different categories, such as nonsteroidal anti-inflammatory drugs (ibuprofen, ketoprofen, naproxen, diclofenac), anti-epileptic (carbamazepine), and anti-microbial (trimethoprim), were investigated in wastewater of the urban areas of Ghaziabad and Lucknow, India. Samples were concentrated by solid phase extraction (SPE) and determined by high-performance liquid chromatography (HPLC) methods. The SPE-HPLC method was validated according to the International Conference on Harmonization guidelines. All the six drugs were detected in wastewater of Ghaziabad, whereas naproxen was not detected in Lucknow wastewater. Results suggest that levels of these detected drugs were relatively higher in Ghaziabad as compared to those in Lucknow, and diclofenac was the most frequently detected drug in both the study areas. Detection of these drugs in wastewater reflects the importance of wastewater inputs as a source of pharmaceuticals. In terms of the regional distribution of compounds in wastewater of two cities, higher spatial variations (coefficient of variation 112.90–459.44 %) were found in the Lucknow wastewater due to poor water exchange ability. In contrast, lower spatial variation (162.38–303.77 %) was observed in Ghaziabad. Statistical analysis results suggest that both data were highly skewed, and populations in two study areas were significantly different (p?NSAIDs) posed high (RQ >1) risk to all the test species. The present study would contribute to the formulation of guidelines for regulation of such emerging pharmaceutical contaminants in the environment.  相似文献   

2.
The concentrations of trihalomethanes (THMs), including chloroform, bromodichloromethane, dibromochloromethane, and bromoform, and haloacetic acids (HAAs; monochloroacetic acid, monobromoacetic acid, dibromoacetic acid, dichloroacetic acid, and trichloroacetic acid) were measured in tap waters passing through water distribution systems of six water treatment plants in Seoul, Korea, and their associated health risks from exposure to THMs through ingestion, dermal contact, and inhalation were estimated using a probabilistic approach. The concentration ranges for total THMs and HAA5 were 3.9–53.5 and <LOD–49.5 μg/L, respectively. Among DBPs, chloroform, bromodichloromethane, dichloroacetic acid, and trichloroacetic acid were the most frequently detected. Spatial and seasonal variations in concentrations of THMs and HAAs in the six water distribution systems were significant (P?<?0.001).The mean lifetime cancer risks through ingestion, dermal contact, and inhalation during showering ranged as 7.23–10.06?×?10?6, 2.19–3.63?×?10?6, and 5.22–7.35?×?10?5, respectively. The major exposure route to THMs was inhalation during showering. Sensitivity analysis showed that shower time and shower frequency had a great impact on the lifetime cancer risk by the exposure to THMs in tap water.  相似文献   

3.
Occurrence and behaviour of 4-nonylphenol in river water of Germany   总被引:1,自引:0,他引:1  
An analytical method composed of solid-phase-extraction (SPE) followed by gas chromatography-mass spectrometry (GC-MS) has been developed to investigate the occurrence and the behaviour of the endocrine disruptor 4-nonylphenol (4-NP) in river water of Germany. 16 Para-isomers of the complex mixture of 4-NP isomers have been resolved in the SPE-extracts of river water samples. The mass spectra indicate the presence of four distinct groups of isomers. The different groups are characterised by different base peaks of the mass spectra dependent on the substitution of the alpha-carbon on the alkyl chain. The different isomers show (i) alpha-methyl, alpha-ethyl (base peak 149), (ii) alpha-dimethyl (base peak 135), (iii) alpha-methyl, alpha-propyl, alpha-butyl (base peak 121) and (iv) alpha-methyl, alpha-propyl, alpha-butyl (base peak 107) configuration of the alkyl chain. The recovery of the unbranched compound 4-n-NP was > or = 90%. Detection limit and determination limit of the whole analytical procedure were 6 ng L(-1) and 25 ng L(-1), respectively with a relative standard deviation of 11.7%. The concentration of the sum of the 4-NP isomers in all samples of river water ranged from 28 ng L(-1) (Elbe River) to 1220 ng L(-1)(Oder River). In a period of a higher river water level, a higher amount of 4-NP was detected in the Oder River than in a period of a lower water level. Therefore dilution was not the determinant factor of the 4-NP concentration in river water. The diurnal dynamics of the sewage treatment works (STWs) have to be considered as an influencing factor for the presence of 4-NP in river water.  相似文献   

4.
Occurrence and fate of pharmaceuticals and personal care products (PPCPs) in drinking water was investigated in southern China. Fifteen and twelve PPCPs were detected with concentrations of 0-36 ng L(-1) in source water and of 0-20 ng L(-1) in treated water, respectively. Four PPCPs were detected with concentrations of approximately 1 ng L(-1) in drinking water of distribution network. Conventional water treatment processes removed the types and average concentrations of PPCPs by 30% and above 50%, respectively. Advanced water treatment processes were more efficient in the removal of most PPCPs, with the types and concentrations reduced by 50% and approximately 90%, respectively. Molecular properties of PPCPs had an important influence on their behaviors during water treatment. pK(a) (acidity coefficient) and K(oc) (organic carbon partition coefficient) of PPCPs appeared to have a combined effect on PPCPs removal during coagulation and oxidation. Adsorption and biodegradation were two possible mechanisms responsible for PPCPs removal during sand filtration.  相似文献   

5.
6.
Perchlorate is known to competitively interfere with iodide uptake by the thyroid gland and thereby human exposure to perchlorate is a public health concern. Prevalence of perchlorate in dairy milk is documented; nevertheless, co-occurrence of perchlorate with other thyroid-binding monovalent ions such as iodide and nitrate is not well understood. In this study, we analyzed perchlorate, iodide, and nitrate-N in dairy milk, water and other dairy-related samples collected from Japan and Sri Lanka. Concentrations of perchlorate in Japanese dairy milk samples ranged from 1.03 to 14.1 ng ml(-1); the corresponding concentrations in dairy milk and powdered milk from Sri Lanka were 1.14-38.5 ng ml(-1). Perchlorate concentrations in commercial milk were significantly higher in Japan than in Sri Lanka, while iodide and nitrate levels in milk between the two countries were comparable. All three ions were ubiquitously found in water samples from Japan and Sri Lanka. Analysis of colostrum and raw milk collected from cows fed with the same feed for over 30 days showed no significant temporal variations in perchlorate, iodide and nitrate-N concentrations. A significant positive correlation was found between the concentrations of perchlorate and iodide in Japanese commercial milk. The concentrations of perchlorate and nitrate-N in water samples analyzed from both countries also showed a significant positive correlation. The exposure estimation revealed that dairy milk provides a greater source for perchlorate and iodide, while water predominantly contributes nitrate-N intake for all age groups in both counties. Infants and children demonstrated the highest estimated perchlorate, iodide and nitrate-N intake on a body weight basis in comparison to other age groups. Therefore, further studies of risk associated with perchlorate may need to reconsider co-existence of iodine and other iodide transport inhibitors in food.  相似文献   

7.
The environmental impacts of various hydrogen production processes are evaluated and compared, considering several energy sources and using life cycle analysis. The results indicate that hydrogen produced by thermochemical water decomposition cycles are more environmentally benign options compared to conventional steam reforming of natural gas. The nuclear based four-step Cu–Cl cycle has the lowest global warming potential (0.559 kg CO2-eq per kg hydrogen production), mainly because it requires the lowest quantity of energy of the considered processes. The acidification potential results show that biomass gasification has the highest impact on environment, while wind based electrolysis has the lowest. The relation is also investigated between efficiency and environmental impacts.  相似文献   

8.
In order to promote pollutant monitoring and preservation of water resources, we evaluate the spatiotemporal trends in recent water quality conditions in Japanese rivers. Trend analysis is conducted on the 92 major rivers in Japan using the available water quality data recorded from 1992 to 2005 and the characteristics of major pollutants in these rivers are analyzed. Spatial and temporal analysis of trends for six water quality indicators is conducted using the Mann Kendall test, a non-parametric statistical method. The indicators analyzed are biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP) and pH. The majority of sampling locations monitoring BOD, COD, TN and TP show trends toward decreasing concentrations over time. Many sampling locations show increasing DO concentrations. Our results show that water quality in Japanese rivers has improved dramatically over the past decade, although there are still problems in some places, most notably in the Hokkaido, Kanto, Kinki and Kyushu regions. The improvements seen in water quality appear to be the result of improved wastewater treatment and other water quality improvement efforts achieved through government initiative.  相似文献   

9.
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   

10.
A series of bioassays with fish was developed in order to evaluate toxicological aspects of polluted rivers in The Netherlands. A long term exposition of trout to riverwater under standardized conditions enables the detection of pathological effects such as growth retardation, liver and kidney enlargement and changes in clinical blood parameters. Bioaccumulation of heavy metals and organochlorine compounds can also be measured. Embryo-larval tests with trout were less suitable, because of yearly variations in egg quality. In the near future, sister chromatid exchange (SCE) assays in vivo with Nothobranchius may become available for the detection of mutagenic effects. It was possible to measure trends in toxicological quality of Rhinewater with these tests. However extrapolation of results to ecosystems and tracing of the causes of changes occurring in waterquality are still problematic.  相似文献   

11.
12.
The WWF water risk assessment tool is a universal methodology, as the establishment of its indicators fully consider various types of natural and social environments. When this tool is applied to China, a large country with a complex water situation in a period of rapid development, appropriate localization adjustment is necessary to ensure that indicators are generally stable and assessment results are internationally comparable. Based on the localization of WWF water risk assessment tools, this is the first application assessing water risk in China in terms of physical risks, regulatory risks and reputation risks. It explores the sources of China's water risk from industrial sectors and constructs a classification index system according to the degree of water dependence and the level of water pollution. Using the classification index system and relevant data, we find the key industrial sectors, enterprises and production processes to reduce water risk in China's ten major water valleys and offer some effective and practical management suggestions. Due to the large regional differences of water risk-bearing capacity in China, the assessment results should be interpreted in combination with specific national conditions of China and emphasis should be laid on key areas and industries.  相似文献   

13.
河流水质综合评价方法的统一和改进   总被引:42,自引:3,他引:42  
在分析我国河流水质综合评价方法存在的问题以及河流水质综合评价方法研究现状的基础上 ,以国家对全国水环境质量系统管理需要为目的 ,提出了对河流水质综合评价方法的要求 ,并针对综合污染指数法的缺陷 ,提出了改进的综合水质指数方法  相似文献   

14.
15.
This paper addresses the future of environmental assessment (EA) practice in light of a rapidly changing world. We apply a literature review-based methodology to firstly identify key global megatrends and then reflect upon the implications for EA practice based on some known challenges. The key megatrends identified are synthesised into six categories: i) demographics, ii) urbanization, iii) technological innovation, iv) power shifts, v) resource scarcity and vi) climate change. We then discuss the implications of these megatrends for EA practice against four known EA challenges namely: dealing with i) complexity and uncertainty, ii) efficiency, iii) significance and iv) communication and participation. Our analysis suggests important implications for EA practice such as: increased difficulties with accuracy of prediction; the need for facilitative adaptation; an increase in the occurrence of unexpected events; higher expectations for procedural efficiency; challenges with information and communication management; dealing with significance judgements; and mitigation amidst resource scarcity and increasing pressures on earth systems. The megatrends underscore the need for continued evolution of EA thinking and practice, especially moving away from seeking a predictable single future or outcome towards the possibility of multiple scenarios with associated adaptability and enhanced system resilience capable of responding to rapid change.  相似文献   

16.
17.
Fractionation of metals in natural sediment and suspended particulate matter (SPM) of Tadjan River is investigated. Competitive sorption, sorption capacities of sediment and SPM as well as fractionation of metal-loaded sediment and SPM are also examined. A risk assessment code (RAC) is applied to estimate the risk of heavy metals release into the environment during the sorption process. Results revealed that sediments and SPM containing more than 25 % of clay minerals and higher amounts of calcite have great capacity of metal sorption, particularly for Cu, Ni, and Mn. Assessing the risk of metals release prior to and following sorption tests indicates that RAC of metals would significantly increase from the level of no or low risk in natural sediment and SPM to high or very high risk after sorption. The Langmuir model reveals that the highest affinity for Cu, Mn, and Ni in sediment is the organic fraction. The classic isotherm models of Freundlich and Langmuir can fit the data from chemical extraction studies of adsorbed metals, indicating that although sorption was apparently a physical and chemical process in the river, isotherm models can be used to simulate the sorption and accumulation in different geochemical phases within the particulate matter.  相似文献   

18.
Urban and agricultural areas affect the hydraulic patterns as well as the water quality of receiving drainage systems, especially of catchments smaller than 50 km(2). Urban runoff is prone to contamination due to pollutants like pesticides or pharmaceuticals. Agricultural areas are possible sources of nutrient and herbicide contamination for receiving water bodies. The pollution is derived from leaching by subsurface flow, as well as wash-off and erosion caused by surface runoff. In the Luxembourgish Mess River catchment, the pharmaceutical and pesticide concentrations are comparable with those detected by other authors in different river systems worldwide. Some investigated pesticide concentrations infringe current regulations. The maximum allowable concentration for diuron of 1.8 μg l(?-?1) is exceeded fourfold by measured 7.41 μg l(?-?1) in a flood event. The load of dissolved pesticides reaching the stream gauge is primarily determined by the amount applied to the surfaces within the catchment area. Storm water runoff from urban areas causes short-lived but high-pollutant concentrations and moderate loads, whereas moderate concentrations and high loads are representative for agricultural inputs to the drainage system. Dissolved herbicides, sulfonamides, tetracyclines, analgesics and hormones can be used as indicators to investigate runoff generation processes, including inputs from anthropogenic sources. The measurements prove that the influence of kinematic wave effects on the relationship between hydrograph and chemographs should not be neglected in smaller basins. The time lag shows that it is not possible to connect analysed substances of defined samples to the corresponding section of the hydrograph.  相似文献   

19.
20.
The concentration of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn metals in water and sediments of Yamuna river were determined by atomic absorption spectrophotometry in the year 1981. The data showed that there was considerable variation in the concentration of elements from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wasters being added to the river at different sampling stations. The sediment samples collected from different sampling stations were also analysed for calcium carbonate, organic matter, potassium, and phosphorus.  相似文献   

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