Spatial distribution of cyanotoxins and ratios of microcystin to biomass indicators in the reservoirs of the Volga,Kama and Don Rivers,the European part of Russia     

《Limnologica》2020

We studied the distribution of cyanotoxins and potential producers, as well as the variability of microcystin to biomass parameters (chlorophyll-a; MC/Chl-a; and biovolume; MC/BV) in 12 drinking water reservoirs of the world’s largest reservoir system, the Volga-Kama-Don cascade (European part of Russia) during the summers of 2016 and 2018. MC concentrations varied from below 0.1 μg L⁻¹ in June up to 16.4 μg L⁻¹ in August and exceeded 1 μg L^-1 in 25 % of the samples. This MC variability was associated to changes in the abundance of widespread bloom formers such as Microcystis spp., Dolichospermum spp. and Planktothrix agardhii. Ratios of MC/Chl-a and MC/BV_cyano ranged up to 0.88 μg μg⁻¹ and 4.5 μg mm⁻³, respectively. Together with microcystin profiles MC/BV_cyano ratios characterized cyanobacterial populations along the reservoir cascade and they indicated a potential toxin hazard better than MC/Chl-a. The neurotoxin anatoxin-a was observed only in the most southern and hypereutrophic Tsimlyansk Reservoir (maximum 0.01 μg L⁻¹). Toxin gene analysis revealed that MC mostly originated from Microcystis and Dolichospermum. During their co-existence up to 14 MC congeners co-occurred. Cuspidothrix issatschenkoi cf. Raphidiopsis mediterranea was identified as possible neurotoxin producers.  相似文献   

Comparative analysis of bacterial contamination in tap and groundwater: A case study on water quality of Quetta City,an arid zone in Pakistan          下载免费PDF全文

Tanzeel Khan  Muhammad Akhtar Malik  Gohram Malghani  Rabia Akhtar 《地下水科学与工程》2022,10(2):153-165

Water is an essential element on earth, which provides human a variety of services in domestic use, agriculture, or industries. However, some serious health risks of drinking water are associated with microbial contamination, particularly with fecal matter. Therefore, microbial quality assessment is considered to be a necessary component of water quality assessment. This study investigates microbial contamination of water distributary system around the city by comparing groundwater (GW) and tap water (TW) quality in Quetta city. 31 GW samples and 31 TW samples were collected in the study area during the months of September, October, and November. Fecal coliform test was carried out in laboratory and their average total coliform contamination was computed. Results showed that the TW sample were all contaminated by coliform except for Chiltan town, hence are not considered suitable for drinking without any treatment according to WHO drinking water quality standards. The average coliform concentrations were 12 in Quetta main city, 11.6 in Jinnah town, 5.3 in Satallite town, 10 in Shahbaz town and 5 in Brewery town (0/100 mL CFU) and the TW samples from the three towns were even more contaminated with E.coli. Whereas among the GW, average microbial concentrations were 1.8 in Quetta main city, 2 in Satallite town, 1.4 in Shahbaz town, and 0.4 in Chiltan town (0/100 mL CFU), respectively, which shows that the contamination is occurring within the water distributary pipeline system when the water flows through the pipelines. Moreover, this research will be valuable for researchers and administrative authorities to conduct elaborative studies, and develop new policies to prevent further deterioration of drinking water in the water distribution system by pathogenic microorganisms and ensure safe drinking water to the public of Quetta city.  相似文献   

Cryptosporidium Oocysts in Drinking Water Supply of Chennai City,Southern India     

Muthukumar Anbazhagi  Dhanraj Loganathan  Subramani Tamilselvan  Raj Jayabalou  Senthilkumar Kamatchiammal  Rakesh Kumar 《洁净——土壤、空气、水》2007,35(2):167-171

Cryptosporidium is an enteric parasitic protozoan capable of causing chronic diarrhea. One of the most common modes of transmission is through faeces‐contaminated water. This study determines the distribution of Cryptosporidium oocysts for the first time in Chennai City's drinking water supply. 199 drinking water samples were collected from ten zones of the city. In the water samples Cryptosporidium, a common pathogenic protozoan of the gastrointestinal tract, has been analyzed physico chemically as well as microbiologically for heterotrophic organisms and total coliforms (TC). The studies revealed that three zones of the city were highly contaminated with coliforms and parasitic protozoa. A statistical analysis was done to find any correlation between heterotrophic organisms, total coliforms, and oocysts. Even though a positive correlation exists between oocysts and bacteriological parameters, a regression equation shows that heterotrophic plate count (HPC) and total coliforms were only 20% responsible for the presence of oocysts. The level of Cryptosporidium oocysts isolated from the water samples may present a public health hazard although no major outbreaks have so far been reported in Chennai City. Routine surveillance of water quality throughout the city is needed to curb the pollutants.  相似文献   

Alternative Validation of a LC-MS/MS-Multi-Method for Pesticides in Drinking Water     

Alexander Müller  Dirk Flottmann  Wolfgang Schulz  Wolfram Seitz  Walter H. Weber 《洁净——土壤、空气、水》2007,35(4):329-338

The development of instrumental analytics such as the LC-MS/MS has made it possible to quickly determine many component concentrations in a single chromatogram. However, the validation of such multi-methods needs new strategies for robustness and optimization. Statistical execution of analytical tests is one tool that can be utilized to meet this requirement. A Central Composite Design (CCD) was utilized for the validation of an LC-MS/MS multi-method for 84 analytes. The experimental design includes six design variables and two non-design variables (response variables). Concentration, ionization temperature, dwell time, gradient, flow (of eluent), and spraying/curtain gas (continuous design variables) were varied on five different levels; the whole design encompassed 91 runs. To investigate the robustness of a LC-MS/MS method both peak sensitivity and chromatographic separation had to be verified. Therefore, two non-design variables were necessary. The distribution of the peaks over analysis time was applied to describe the quality of the chromatographic separation. The sensitivity was described with the signal to noise ratio (S/N). The evaluation of the measured data was accomplished with the Analysis of Variance (ANOVA) and the Response Surface Methodology (RSM). Three main effects (concentration, ionization temperature, dwell time) and no significant interaction effect were found for the response variable “S/N”. The variables of concentration, ionization temperature, and dwell time had no significant effects for the response variable “S/N”. The ANOVA of the response variable chromatographic separation abandoned no significant effects as well. Therefore, robustness of the method can be guaranteed for all non significant design variables.  相似文献   

平原水库饮用水水质净化的有效途径   总被引：2，自引：0，他引：2  

李兰贵  牛建辉  胡荣花  赵卫国 《地下水》2003,25(3):178-180

针对地表饮用水水源地蓄水后水质发生变化的情况，结合平原水库工程管理和水源保护工作的实践，分析了地表饮用水水源地产生富营养化的原因及危害，阐述了生物净化水质的机理，提出了利用生物净化水质技术，通过对生物种群结构和生物量的科学调控，消耗水体中的营养物质，达到既能充分利用营养资源，又可净化水质，改善水体环境的理想效果，为地表饮水水源地的水质净化找到了有效途径和方法。  相似文献   

Determination of the origin of the Helvadere drinking springs by means of hydrochemical and isotopic techniques, Aksaray, Central Anatolia, Turkey     

M. Afşin 《Environmental Geology》2000,39(10):1190-1196

The main aquifer of the Helvadere springs that emerges on the strike-slip of the Hasanda?? fault set alongside the Tuzgölü (salt lake) fault zone, and trends in a NW–SE direction of Aksaray city, in the western part of Central Anatolia, is the exposed rocks of Hasanda?? which are volcanics that have distinct hydrogeological properties. The meteoric origin of the spring waters is deduced from hydrochemical and environmental isotope (¹⁸O, ²H, ³H) studies. The springs have high discharge (Q>100?l/s) and low ion concentrations because of fast circulation along the groundwater flow path in the aquifer. Furthermore, because it has Ca-Na-Mg-HCO₃ hydrochemical facies, it conforms to high standards of drinking and irrigation water.  相似文献   

Groundwater quality and its suitability for drinking and agricultural use in Chithar River Basin, Tamil Nadu, India   总被引：8，自引：0，他引：8  

T. Subramani  L. Elango  S. R. Damodarasamy 《Environmental Geology》2005,47(8):1099-1110

Hydrochemistry of groundwater in Chithar Basin, Tamil Nadu, India was used to assess the quality of groundwater for determining its suitability for drinking and agricultural purposes. Physical and chemical parameters of groundwater such as electrical conductivity, pH, total dissolved solids (TDS), Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^–, HCO₃^–, CO₃^2–, SO₄^2–, NO^–₃, F^–, B^– and SiO₂ were determined. Concentrations of the chemical constituents in groundwater vary spatially and temporarily. Interpretation of analytical data shows that mixed Ca–Mg–Cl, Ca–Cl and Na–Cl are the dominant hydrochemical facies in the study area. Alkali earths (Ca²⁺, Mg²⁺) and strong acids (Cl^–, SO₄^2–) are slightly dominating over alkalis (Na⁺, K⁺) and weak acids (HCO₃^–, CO₃^2–). The abundance of the major ions is as follows: Na⁺ Ca²⁺ Mg²⁺ > K⁺ = Cl^– > HCO₃^–> SO₄^2– > NO₃^– > CO₃^2– . Groundwater in the area is generally hard, fresh to brackish, high to very high saline and low alkaline in nature. High total hardness and TDS in a few places identify the unsuitability of groundwater for drinking and irrigation. Such areas require special care to provide adequate drainage and introduce alternative salt tolerance cropping. Fluoride and boron are within the permissible limits for human consumption and crops as per the international standards.  相似文献   

华东部分铀矿区内大气和饮用水体放射性水平调查研究     

张洪  周甄龙 《铀矿地质》1999,15(6):367-371

通过对华东地区２１ 个铀矿区内居民居住环境大气中氡及其子体α潜能浓度的调查,结果表明：居民居室外氡浓度均值范围为６．７３—１３２．９ Ｂｑ／ｍ ３,氡子体α潜能浓度均值范围为１１．０—７８．８ｎＪ／ｍ ３。居室内的平均氡浓度均值范围为１４．５—１８５．８ Ｂｑ／ｍ ３,氡子体α潜能浓度均值范围为１３．８—１０４．２ ｎＪ／ｍ ３;对居民饮用水源的取样分析表明,铀浓度均值范围为０．１２—１．６８ μｇ／Ｌ,钍浓度均值范围为０．０２—０．４２ μｇ／Ｌ,镭－２２６ 浓度均值范围为０．９０—１２．１ ｍ Ｂｑ／Ｌ,与全国和当地的放射性天然本底水平比较接近,均属正常本底水平。  相似文献   

An Approach for Classification of Groundwaters by Synchronous Fluorescence Spectroscopy and Discriminant Analysis     

W. Geyer  L. Brüggemann  U. Schmitz 《洁净——土壤、空气、水》1996,24(5):206-211

Monitoring and evaluation of groundwater quality in drinking water protectorates is of particular interest if the uncontrolled entry of pollutants, for example by infiltrating river water, cannot be excluded. A fluorescence spectroscopic method is presented as possible alternative to the conventional expensive hydrochemical investigations. This method uses the information yielded by synchronous fluorescence spectra. After a Fourier transformation of the original spectra and a following discriminant analysis, the samples can be classified in different groups corresponding to the different types of groundwater. The method was tested in the drinking water protectorate of a waterworks of a German metropolis (Halle, Sachsen-Anhalt). We found a prediction rate of about 90% in the investigated case.  相似文献   

Application of AMD to the Determination of Cropprotection Agents in Drinking Water. Part III: Solid Phase Extraction and Affecting Factors Anwendung der AMD-Technik zur Bestimmung von Pflanzenbehandlungsmittel-Wirkstoffen im Trinkwasser. Teil III: Festphasenextraktion und ihre Einflußfaktoren     

G. Pfaab  H. Jork 《洁净——土壤、空气、水》1994,22(5):216-223

The more sensitive an analysis method the more care must be given to sample preparation. Solid phase extraction (SPE) onto RP 18 phases has established itself as a general purification and enrichment technique for trace components in aqueous samples. Various factors may thereby influence the recovery rate. For example, the ratio amount of sorbent and sample volume should be taken into account to avoid breakthrough of the investigated substance. Extracting phenylurea herbicides from drinking water, the ratio should be 1 g RP 18 sorbent per 1 L water sample. Concerning the flow rate for the fungicides procymidone, vinclozolin, and iprodione, the recovery rate decreases using higher flow rates than 3 or 6 mL/min. In the case of phenylurea herbicides, a flow rate of 10 or 14 mL/min showed best results. Even the coefficient of variation is below ± 5% at these flow rates. Furthermore, the company dependence should be considered because the recovery rate might differ by up to 40% using the nominally identical material. The same applies to the batch dependence of quality from the same company. The concentration of the eluate must also be monitored and carried out with great care to avoid decreasing the recovery rate. Considering these factors of influence, SPE is a very useful tool in sample preparation, particularly if an automated system is used.  相似文献