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1.
Static bioassays were carried out using two aquatic snails (Pilia sp. and Lanistes sp.) as test organisms in soft natural dilution water, with waste drilling fluid as the test material, at 28±2°C. Comparison of results for the control and different concentrations of the waste drilling fluid were made by means of the F-statistic method. The waste drilling fluid was practically non-toxic to the two aquatic snails.  相似文献   

2.
This study aimed to optimise the methodology for the use of Corophium insidiosum in a bioassay. Taking into account that it would be suitable to execute the bioassay with organisms having a good sensitivity during the year and low mortality in control sediment, the influence of different temperatures (10–15–20 and 25°C) has been examined. C. insidiosum was collected during August, November 2005 and January 2006, in Mar Piccolo basin (Ionian sea). The results obtained show that this species mortality in the negative control sediment, ranged from 2.6 ± 0.6% at 10°C in August to 17 ± 2.2% at 20°C in November, at different temperatures tested. At 20°C there were significant differences in mortality among different months examined. Indeed no relationship among months was found at 15°C. Significant differences between August and November at 25°C, between November and January were not found at 10°C. The 96-h LC50 values found for cadmium at all temperature experimental conditions ranged from 2.11 mg/l (1.57–2.82) to 0.70 mg/l (0.54–0.93). The highest values were found at 10°C in November and January. The results showed that the optimal temperature for the bioassay seems to be between 15°C and 20°C. Even if, at 20°C the mortality differs significantly among organisms sampled.  相似文献   

3.
Freshwater cladocera such as Daphnia magna and Ceriodaphnia dubia have been used extensively for freshwater toxicity test worldwide. However, these species may not be indigenous in certain geographical regions, which restrict the utility of these organisms as test species. In the present study, we investigated optimal culture and test conditions for an indigenous freshwater macroinvertebrate of Korea, Moina macrocopa. The culture conditions that were evaluated included water temperature (20°C and 25°C), rearing media (moderately hard water or MHW, with or without selenium supplementation, or Elendt M4), and food density (2.5 × 107 and 5 × 107 cells/mL of Selenastrum capricornutum), and their effects on the life history characteristics of M. macrocopa were determined. Population growth rate of M. macrocopa was maximized at 25°C with 5 × 107 cells/mL of algal food density in MHW. A series of chronic three brood reference toxicant tests were conducted under the ideal culture conditions that were identified here, and the results of the tests indicated reliable reproducibility of the test protocol. Optimal culture and test conditions that were identified for M. macrocopa in the present study are suggested for evaluation of chronic toxicity of chemicals and industrial or municipal discharge.  相似文献   

4.
Microbiological quality of crude oil storage tanks was determined. The samples were taken from crude oil storage tanks in three stations, at Ughelli, Escravos and Forcados tank farms in the Delta State of Nigeria. Two tanks were sampled at each station with samples collected from three levels of the tank, namely the oil layer, oil water interface, and effluent layer. Samples from the inner walls and bottom sediment of the only empty tank in Ughelli during the study were also taken. The total heterotrophic count of bacteria and total fungal count were obtained by plating samples on nutrient agar and sabouraud's glucose agar respectively and incubated for 14 days at 28 °C±2 °C. Oilutilizing bacteria and fungi were isolated on oil agar using fungizone and antibiotics to inhibit fungal and bacterial growth respectively. Pure cultures of bacteria and fungi were prepared on nutrient agar and sabouraud's glucose agar respectively at 28 °C±2 °C for 4 days. Isolates were identified using approved standard methods. Three bacterial genera, Pseudomonas, Proteus and Bacillus, and one actinomycete, Actinomyces and two fungal genera, Penicillium and Cunninghamella, were isolated. Pseudomonas was dominant among the bacteria (41.62%) and Penicillium dominant among the fungi (94%). It was also found that the total microbial load of the effluent layer was higher than that of the oil layer.  相似文献   

5.
Greywater from baths, showers and washbasins was collected separately from all other domestic wastewater at a university block of flats with a dual reticulation system and analysed for a range of contaminants including indicator organisms and pathogens. Greywater flow and temperature were also monitored and a diurnal variation was observed. Physical and chemical water quality parameters were similar to previously published data, although measured COD and BOD levels appeared to be lower, possibly due to settlement or biodegradation in the storage tanks. Plate counts and indicator organism concentrations were consistently high suggesting a high level of human bacterial contamination necessitating biological treatment and disinfection if the water is to be used for recycling. However, these high levels of indicator organisms did not correlate to pathogen presence and should not be used as pathogen indicators in greywater. One positive count of Salmonella veltereden was observed as well as low levels of Giardia. Cryptosporidium, Escherichia coli O157:H7, enteroviruses and Legionella were not identified in any of the samples. The research also highlighted a number of problems with the complexity of this type of sampling programme, such as identifying the most likely time to isolate pathogens and analysing an ‘unusual’ water source.  相似文献   

6.
硫化学发光检测器-气相色谱法测定废气中挥发性硫化物   总被引:3,自引:1,他引:2  
采用硫化学发光检测-宽口径石英毛细管柱气相色谱法,建立了废气中羰基硫、硫化氢、二硫化碳、甲硫醇、乙硫醇、甲硫醚、乙硫醚、丙硫醇、异丙硫醇、噻吩及二甲二硫等11种挥发性硫化物的分析方法。硫化学发光检测器的灵敏度、选择性及线性范围均优于传统的火焰光度检测器。进样体积为0.2 ml时,硫化物的检出限为0.03~0.1 mg/m3。实际样品5次测定的相对标准偏差小于5.1%,加标回收率为83.7%~108.8%。测定了某炼油厂酸性水罐尾气、污油罐尾气及瓦斯气中挥发性硫化物,为其恶臭控制与治理提供检测手段和基础数据。  相似文献   

7.
The aim of this work was to monitor the sensitivity of two populations of Corophium orientale (Crustacea: Amphipoda) living at the outfall of two rivers (Magra and Serchio), comparing their responses towards two different toxicant solutions. Sensitivity was monthly checked performing the 96h-LC50 static water only test with Cd(NO3)2 and SDS. If no significant differences were found between the two populations, they could have been employed without distinction to perform sediment toxicity bioassays. As regard to Cd, an increasing in LC50 values from summer to winter was evident in each population (Serchio River: August 2003  =  1,36 mg/l, February 2004  =  7,23 mg/l; Magra River: August  =  1,21 mg/l, April  =  5,01 mg/l). This pattern was correlated to the droop of temperatures in winter period. The responses of the two populations towards the cadmium were compared using the ANOVA. The analysis showed any significant differences between the populations (p  =  0.12). The pattern of sensitivity towards SDS for the population living on Magra River was similar to the same pattern found for Cd; as regard to the population living on Serchio River, data were not enough to describe the annual pattern. Anyway, statistical analysis was performed and no significant differences were found between the two populations (p  =  0.34).  相似文献   

8.
钻井污水化学需氧量的研究   总被引:1,自引:0,他引:1  
针对石油工业钻井污水高化学需氧量(COD)严重超标的状况,对钻井污水的化学需氧量进行研究。分折测定了8种钻井液添加剂(PAN、PAMI、HPAN、柴油、磺化沥青、XY27、CMC、FA367)的COD;重点探讨了钻井液添加剂对钻井污水COD的影响,同时对钻井污水COD处理效果的影响进行了研究。实验结果表明,不同钻井液添加剂对钻井污水的COD的影响程度各不相同;钻井污水中COD值严重超标的主要因素是钻井液添加剂;并且钻井液添加剂浓度与其对应的COD之间存在良好的一元线性关系。根据一元线性回归方程可较好地预测油田现场各钻井液添加剂对COD的影响,为解决钻井污水处理这一难题提供科学依据。  相似文献   

9.
北京市废弃物处理温室气体排放特征   总被引:1,自引:0,他引:1  
基于《2006年IPCC国家温室气体清单指南》推荐的方法,结合《省级温室气体清单编制指南(试行)》和《城市温室气体核算工具指南》的部分数据与核算范围,针对固体废弃物填埋、焚烧和废水处理等过程,核算了北京市2005-2014年废弃物处理过程中温室气体总排放量。结果表明:2005-2014年北京市废弃物处理过程温室气体总排放量呈逐渐上升趋势,2014年温室气体总排放量比2005年增长98%。10年间,固体废弃物填埋过程一直是最主要的温室气体排放源,到2014年排放量达到最大,为416.3×104t二氧化碳当量(CO2e)。废弃物填埋、废水处理和废弃物焚烧过程占总排放量的比例分别为78.5%(CO2e质量分数,下同)、13.5%和8%。结合已有研究,系统优化国内7个典型城市废弃物处理温室气体排放因子,核算7个城市排放情况,并对比分析了北京市排放情况。  相似文献   

10.
Marine sediment toxicity tests are widely applied in monitoring programs, yet relatively little is known about the comparability of data from different laboratories. The need for comparability information is increased in cooperative monitoring programs, where multiple laboratories (often with variable skill levels) perform toxicity tests. An interlaboratory comparison exercise was conducted among seven laboratories in order to document the comparability of sediment toxicity measurements during the Bight'98 regional sediment survey in southern California. Sediments from four stations in Los Angeles and Long Beach Harbors were tested using a 10-day survival test of the amphipod Eohaustorius estuarius. All laboratories successfully performed the sediment test and associated reference toxicant test. Statistically significant differences were found in mean amphipod survival rates among some laboratories for the field-collected sediments, but there was little evidence of a consistent bias among laboratories. Although the reference toxicant test indicated a five-fold variation in test sensitivity among laboratories, these results were not accurate predictors of interlaboratory performance for the sediment tests. The laboratories demonstrated excellent concordance (Kendall's W = 0.91) in ranking the field-collected sediments by toxicity. Agreement on classifying the sediments into categories (nontoxic, moderately toxic, and highly toxic) based upon the percent of survival was best for highly toxic sediments. An analysis of test precision based upon the variance among replicates within a test indicated that the measured survival rate for a sample may vary by up to 12 percentage points from the actual response.  相似文献   

11.
化工园区污水特征分析及生物毒性研究   总被引:3,自引:0,他引:3  
对天津市某化工园区9个主要污染企业及总排放口的废水进行监测分析,测定了12项水质常规指标和8项重金属指标,采用主成分分析法和生物毒性测试对化工区废水的水质进行了综合评价。结果表明,水质指标中大部分常规项目(如COD、氨氮和重金属含量)在多数企业污水中都符合排放标准,总氮、总磷污染较重,其中磷的污染最严重,最高超标23.83倍;影响污水性质的第一主成分为氯化物、电导率、全盐量和Cr,第二主成分为溶解氧、悬浮物、氨氮、总氮、总磷和As;废水具有一定的生物毒性,且不同化工企业之间毒性差异较大。水质化学测定的结果和生物毒性程度有一定相关性,但也存在差异,应该结合两者综合评价水质污染特征。  相似文献   

12.
Organochlorine pesticide concentrations, particularly those of the DDT family and of toxaphene, were measured by gas chromatography in samples of liver and body fat taken from Australian freshwater crocodiles Crocodylus johnstoni at three locations along the Ord River in Western Australia. The three sampling sites were the irrigation area, downstream of the irrigation area, and well upstream of the irrigation area; the last site serving as the control. DDT and toxaphene were applied in large and known quantities to cotton grown in the Ord Irrigation Area from 1964 to 1974. Thus the residues in the crocodile tissues are representative of the situation almost thirty years after the use of DDT and toxaphene ceased in the area. Very high concentrations of p,p'-DDE and toxaphene were found in the lipid-rich tissues that were examined. Livers and body fat from estuarine crocodiles Crocodylus porosus from the downstream site were also analysed. As p,p'-DDE and toxaphene are both known to be disruptive of endocrine systems, a range of blood parameters, including estradiol and testesterone concentrations, were also measured for all the animals studied. The ovaries and testes of the freshwater crocodiles were also examined histologically. There were no obvious effects on blood chemistry or gonad histology of the large burden of pesticides and their metabolites carried by exposed animals, although the limited number of samples and the variability of the breeding state of the animals examined may have masked possible effects. The isolation of the area, the accurately known applications of DDT and toxaphene, and the simplicity of the drainage system make the lower Ord River a unique natural laboratory for studying the long term breakdown and effects of pesticides applied in a tropical environment.  相似文献   

13.
Fly ash samples were taken from solid waste incinerators with different feeding waste, furnace type, and air pollution control device in six cities of Zhejiang province. The solid waste incinerators there constitute one fifth of incinerators in China. Heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in the fly ash. Moreover, the fly ash samples were extracted by toxicity characteristic leaching procedure (TCLP). The biotoxicity of the leachate was evaluated by Chlorella pyrenoidosa. High variation and contents were found for both the heavy metals and PCDD/Fs. The contents of Zn, Cu, As, Pb, Cd, Cr, Ni, and Hg in the fly ash samples varied from 300 to 32,100, 62.1–1175, 1.1–57, 61.6–620, 0.4–223, 16.6–4380, 1.2–94.7, and 0.03–1.4 μg g−1 dw, respectively. The total contents of 17 PCDD/Fs varied from 0.1128 to 127.7939 μg g−1 dw, and the 2,3,7,8-TeCDD toxic equivalents (TEQ) of PCDD/Fs ranged from 0.009 to 6.177 μg g−1 dw. PCDF congeners were the main contributor to the TEQ. The leachate of the fly ash showed biotoxicity to C. pyrenoidosa. A significant correlation was found between the Cd and EC50 values. Further research is required to investigate the environmental impact of the various pollutants in the fly ash.  相似文献   

14.
Combining genotoxicity/mutagenicity tests and physico-chemical methodologies can be useful for determining the potential genotoxic contaminants in soil samples. The aim of our study was to evaluate the genotoxicity of soil by applying an integrated physico-chemical-biological approach. Soil samples were collected at six sampling points in a Slovenian industrial and agricultural region where contamination by heavy metals and sulphur dioxide (SO2) are primarily caused by a nearby power plant. The in vitro alkaline version of the comet assay on water soil leachates was performed with Caco-2 and HepG2 cells. A parallel genotoxicity evaluation of the samples was performed by Ames test using Salmonella typhimurium and the Tradescantia micronucleus test. Pedological analyses, heavy metal content determination, and different physico-chemical analyses, were also performed utilizing standard methodology. Water leachates of soil samples were prepared according to standard methods. Since only a battery of biotests with prokaryotic and eukaryotic organisms or cells can accurately estimate the effects of (geno)toxicants in soil samples and water soil leachates, a combination of three bioassays, with cells or organisms belonging to different trophic levels, was used. Genotoxicity of all six water soil leachates was proven by the comet assay on both human cell lines, however no positive results were detected by bacterial assay, Ames test. The Tradescantia micronucleus assay showed increase in micronuclei formation for three samples. According to these results we can assume that the comet assay was the most sensitive assay, followed by the micronucleus test. The Ames test does not appear to be sensitive enough for water soil leachates genotoxicity evaluations where heavy metal contamination is anticipated.  相似文献   

15.
The present study was aimed to make an assessment of health risk due to pollution and human pathogenic bacteria associated with the recreational and drinking water sources in twin densely populated holy Indian cities Ayodhya and Faizabad. Though physicochemical studies revealed that the water available in the area is under recommended limits for human use, it is unsafe on account of poor microbiological quality of surface and ground water in the region. The most probable number (MPN) test results revealed the preponderance of ≥2,400 total coliforms (TC) (100 ml) − 1 in river, pond, dug well and kund waters. Contrary to that, 94% tube wells, 32% hand pumps and 25% piped supply water were under safe limits having <3 TC (100 ml) − 1. The shallow depth (~40 ft), water logging and presence of septic tanks in the near vicinity are the possible reasons of poor microbial quality of hand pump drinking water. The municipal supply water passes along sewage line where loose connections and/or cracks in pipe lead to mixing and contamination. The significant best quality of tube well water evident from the absence of TC could be attributed to the depth of well ≥150 ft and usually their location away from the habitation. A total of 263 bacteria from 186 water samples were isolated, and at least five genera of enteric bacteria from various water sources were identified morphologically and biochemically as Escherichia coli, Klebsiella sp., Enterobacter sp., Shigella sp. and Salmonella sp. The serotyping of 72 E. coli and 36 Salmonella sp. revealed 51 as E. coli O157 and 20 as Salmonella sp. The presence of enteric pathogens in water sources pose threat to human health and therefore call for immediate remedial measures.  相似文献   

16.
Precipitation chemistry programs in different regions of the world have different quality control limits for ion balance parameter IPD in wet deposition monitoring (R). The range of R values was calculated by assuming sample rainwater models in this paper. It was found that R was influenced by the inorganic ion types, total ion concentrations (IS) and the accuracy of the measurements (a i ). R was defined and calculated as a function of a i and ion concentration C i . R values of different types of wet deposition (including ocean type, continent type and combined oceanic and continental deposition) were different. There were also differences between the samples of the same type if the samples had different total ion concentrations. When IS>100 μeq/L, the ranges of R of ocean type deposition, continent type deposition and combined oceanic and continental deposition were 5∼7%, 5∼9% and 5∼11%, respectively. When IS<50 μeq/L, if a i was 100%, the range of R was 33∼71% because of the lower accuracy. It was also found that R of each criterion was in the range of R as calculated in this paper when IS≥50 μeq/L, but when IS<50 μeq/L, the criteria varied greatly in their R values.  相似文献   

17.
Toxic effects of pollutants on marine organisms can be studied both by performing field measurements, and by undertaking laboratory simulation experiments. Here is described the effect of trace metals Zn, Cd, Pb and Cu on the clam Scrobicularia plana along a salinity gradient simulated in a hypothetical estuary using simulation experiments. The simulator produces a continuous entry of trace metals into the estuary through injection in the lower salinity tank of the system. The clams were exposed during two weeks to different concentration of trace metals to assess the bioaccumulation process along a salinity gradient. Bivalves were analysed for body tissue residue to determine the bioaccumulation factors related to each metal and the salinity influence was addressed. Differences among tanks were observed as a result of the salinity gradient. In the achieved assays, the mechanism of bioaccumulation of Zn and Cd in organisms was more efficient at high salinity values. Bioaccumulation factors for both metals showed a linear increase with the increase of salinity values. It seems that the mechanism of bioaccumulation of Pb and Cu in organisms was dependent on two simultaneous processes: the proximity to the input point of metals and the low salinity values.  相似文献   

18.
The acute salinity tolerance of three tropical freshwater cladoceran species, M. macleayi, C. rigaudii and D. brachyurum was determined. The existence of these species represented new records for Trinidad and Tobago, a tropical Caribbean island. It has a large oil based industry, in which, the primary effluent (saline produced water) is discharged directly into many freshwater systems. Cladoceran species are used routinely in temperate regions, to assess the impacts of chemicals and effluents in freshwater systems. However, relatively few studies have assessed the salinity tolerance of these organisms. Test organisms were assayed using seven salinity treatments (0, 1, 3, 5, 10, 15, 20, 25‰) prepared by volumetrically mixing natural filtered seawater with dilution water. C. rigaudii had a 48 h LC50 of 1.6‰, M. macleayi 1.5‰ and D. brachyurum <1‰. The CSmax (critical salinity maximum) for C. rigaudii and M. macleayi was 3‰ after 48 h, compared to 1‰ for D. brachyurum. There was no salinity value at which there was 100% survival. The resulting salinity response curve was a straight line which indicated that each species was intolerant of salt. Consequently, any of these can be considered as a representative freshwater organism for toxicity testing in Trinidad and Tobago.  相似文献   

19.
Mine waste water at South Kaliapani usually contains toxic levels of hexavalent Cr(VI). The present in situ study was conducted at South Kaliapani chromite mine area in Orissa state, India, to assess the phytoremediation ability of three plants, namely, rice (Oryza sativa L.), paragrass (Brachiaria mutica), and an aquatic weed (Eichhornia crassipes), in attenuating Cr(VI) from mine waste water and to correlate the bio-concentration factors (BCF) of Cr. Water hyacinth (E. crassipes) showed 24% to 54% reduction whereas paragrass (B. mutica) was able to reduce 18% to 33% of Cr(VI) from mine water. This reduction was studied over a period of 100 days of plant growth. The reduction was observed through a passage of a sum total of 2,000 sq. ft. cultivated plots and ponds separately. Reduction in Cr(VI) content in mine water varies with plant age as well as with the distance of passage. Cr accumulation and BCF values increased with high soil Cr levels as well as the age of plants. High BCF and transportation index (Ti) values, i.e., 10,924 and 32.09, respectively, were noted for water hyacinth. The Ti values indicated that the root-to-shoot translocation of Cr was very high after 100 days of growth. The total accumulation rate was maximum (8.29 mg Cr kg dry biomass − 1 day  − 1) in paragrass. The BCF values for roots were noted to be higher than those of leaves, stems, and grains of the 125-day-old plants. Hence, paragrass and water hyacinth may be used as tools of phytoremediation to combat the problem of in situ Cr contamination.  相似文献   

20.
The physical (pH, Dissolved Solids, Dissolved Oxygen, conductivity, water depth temperature) and bacteriological (Total coliforms, Faecal coliforms) characteristics of 22 hand-dug wells in oil-rich Niger Delta of Nigeria were investigated. All coliforms counts (Log10 MPN/100 ml) varied from well to well ranging from 0 to 6.0 although faecal coliform counts were markedly lower (0–3.5 vs 1.0–6.0). When both seasons were compared, faecal coliform counts were significantly higher (t test; P < 0.05) during the wet season whereas no significant difference was observed in respect of total coliforms. Unlike the total coliforms, faecal coliform counts increased in wells close to septic tanks during the wet season. Although a declining trend was observed during the wet season, the values of the physical parameters were within WHO limits. The pH was slightly acidic (Mean ± SD: dry season, 6.04 ± 0.66; wet, 6.43 ± 0.62) and may be attributed to emissions from gas flaring and petroleum refining activities, which is common in the area. While the total coliform counts reflected the unsanitary habits of the well users, the detection of faecal coliforms exceeding recommended numbers in 63% of the wells render them unfit for domestic use. The public health implication is obvious considering the increasing number of people using the wells due to the rapid urbanization of the oil-rich region.  相似文献   

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