用Ames试验检测水源水和自来水中的遗传毒性

用微伤寒沙门氏菌／哺乳动物微粒体酶系的Ａｍａｅｓ试验，研究了不同季节物水源水及管网自来水中的遗传毒性，以ＸＡＤ２树脂为吸附剂，以丙酮－甲醇的混合液为洗脱液，浓率水样中的有机物，并对部分阳性水样进行有机成分的定性分析。结果发现：１３个水样中有７个样品在淡需要代谢活化系统Ｓ９的情况下，可诱导鼠伤寒沙门氏菌碱基移码型菌株的回复突变；不同水样在不同季节不同的诱导作用；同时通过ＧＣ／ＭＳ方法分析，发现阳性水     

用Ames试验调查水中致突变物含量──江苏油田饮用水及水源水的污染状况调查

应用鼠伤寒沙门氏菌致突变试验对江苏油田主要饮用水及饮用水源水的致突变物污染状况进行了调查，结果表明，在本检测条件下，江苏油田饮用水及饮用水源水无致突变性。     

用Ames试验调查水中致突变物含量：江苏油田饮用水及水源水的 …

应用鼠伤寒沙门氏菌致突变试验对江苏油田主要饮用水及饮用水源水的致突变物污染状况进行了调查，结果表明，在本检测条件下，江苏油田饮用水及饮用水源水无致突变性。     

南京市主要饮用水源水中有机污染物的遗传毒性研究

运用鼠伤寒沙门氏菌 /哺乳动物微粒体酶系 ( Ames)试验 ( DNA)、SOS/Umu试验 (基因 )和蚕豆根尖微核试验(染色体 )对不同季节 (枯、丰、平 )南京市主要水厂的水源水中有机污染物的遗传毒性进行了研究。以 XAD-2树脂为吸附剂 ,丙酮 -甲醇的混合液为洗脱液 ,浓缩水样中有机物 ,并对部分阳性水样进行了有机组分的定性分析 ( GC/MS法 )及其污染源调查。结果发现 ,不同季节水样均有不同程度的遗传毒性检出 ,其中以上元门水厂水质最劣 ;同时通过 GC/MS法分析 ,发现阳性水样中存在有美国 EPA所列的多种优先污染物以及其它黑名单上所属的有毒有害物质 ,应当引起足够的重视     

响应面法优化养殖水体中炔雌醇的固相萃取条件

在单因素试验、Plackett-Burman设计试验基础上,采用Box-Behnken响应面法对养殖水体中炔雌醇(EE2)的固相萃取条件进行优化。结果表明,洗脱液体积、洗脱液组成和淋洗液体积是影响EE2固相萃取回收率的3个主要因素;EE2的最佳固相萃取条件为:水样pH值为3,进样流量为3.0 mL/min,淋洗液为体积分数为10%的甲醇水溶液,淋洗液体积7.0 mL,洗脱液为乙酸乙酯-正己烷混合溶液(体积比为9∶1),洗脱液体积12.0 mL。该条件下养殖水样中EE2固相萃取回收率为81.6%～86.7%。     

响应面法优化测定水体中微囊藻毒素

针对水体中低浓度微囊藻毒素(MC-RR和MC-LR)的富集、淋洗、洗脱等前处理环节,采用单因素响应面优化法探讨微囊藻毒素前处理的最佳条件。结果表明:采用体积分数为25%的甲醇水溶液能够取得最佳淋洗效果,由One Factor设计优化得到体积分数为75%的甲醇水溶液作洗脱剂,MC-RR和MC-LR最佳回收率为89.4%和90.7%。方法在0.100 mg/L~5.00 mg/L范围内线性良好,MC-RR和MC-LR的检出限分别为0.07μg/L和0.04μg/L,实际水样加标回收率分别为80.6%和84.9%,平行测定结果的RSD分别为1.6%和2.4%。     

典型燃煤电厂机组二氧化碳排放测试及核算研究

为验证二氧化碳排放量的测试技术适用性及可行性,获取燃煤电厂机组碳排放特征,系统比较不同测试方法之间碳排放量的差异,对某典型火电机组二氧化碳排放开展测试,结果表明,不同测试原理及设备二氧化碳排放实测体积分数均较为接近。测试机组CO₂实测体积分数为11.28%～14.21%,与负荷变化呈一定的正相关关系,不同负荷下基准氧含量(体积分数6%)基本无变化。测试机组排放量与负荷正相关,使用了缺省值的指南排放量最高,与其他方法排放量相对偏差均值为31.6%;使用入炉煤实测数据的指南排放量差异不大,相对偏差为0.1%;使用入炉煤实测数据的2版指南排放量高于直接测量法,相对偏差均值为4.9%;直接测量各类方法间相对偏差均值为1.0%,其中在线法与手工法间相对偏差均值为1.2%。CO₂排放强度与负荷负相关,实验条件下,机组负荷越高,碳排放强度越低。     

碘化钾-淀粉试纸法测定余氯

基于余氯对碘化钾的氧化作用和碘淀粉反应，本文提出了测定余氯的碘化钾－淀粉试纸法。研究了最佳测试条件，用于测定医院污水中的余氯，获得满意结果。测量范围为１．０－１０．０ｍｇ／Ｌ。     

高效液相色谱法快速测定水中苦味酸

采用高效液相色谱法,研究了水中苦味酸的快速测定方法,优化了液相色谱的各项分析条件。结果表明,流动相为甲醇:水(0.01%三氯乙酸)(体积比45:55)、柱温40℃、检测波长350 nm为最佳的检测条件,在最佳检测条件下,苦味酸的检出限为0.4 μg/L。地表水和地下水高、中、低3种浓度的加标回收率均在88%以上,相对标准偏差(RSD)均小于5%,污水的加标回收率为71%~90%,RSD为7.9%。     

超高效液相色谱-串联质谱同时测定水中的敌百虫和敌敌畏

建立超高效液相色谱-串联质谱(UPLC-MS-MS)同时测定水中敌百虫和敌敌畏的方法。水样经0.22μm滤膜过滤,直接用超高效液相色谱-三重四极杆串联质谱多级反应监测法(MRM)定量检测敌百虫、敌敌畏。考察了色谱柱、流动相、滤材对分析的影响,并确定了最佳分析条件。最佳条件下,敌百虫、敌敌畏的检出限分别为0.6μg/L和2.3 ng/L。用建立的方法测定了4种实际水样中的敌百虫、敌敌畏,水样加标回收率为82.2%~112.1%。方法简便快捷、绿色环保,适合于地表水及地下水中敌百虫和敌敌畏的同时分析。     

Salmonella mutagenicity analysis of water samples from Çamaltı saltern

Mutagenicity analysis of water samples from Camalti Saltern, Turkey were investigated by applying Salmonella mutagenicity test. Plate incorporation assay was applied in the absence of metabolic activation. XAD 4 and XAD 16 columns were used for the fractionation of the water samples. The results obtained were negative in both TA 98 and TA 100. Although the number of revertants of XAD 16 extract in station B were higher than the revertants in the other stations for TA 98 strain when compared to the solvent control. However this was not significant to be considered as mutagenic. The results were discussed for the future analysis.     

Ascorbic acid reduction of active chlorine prior to determining Ames mutagenicity of chlorinated natural organic matter (NOM)

Many potable water disinfection byproducts (DBPs) that result from the reaction of natural organic matter (NOM) with oxidizing chlorine are known or suspected to be carcinogenic and mutagenic. The Ames assay is routinely used to assess an overall level of mutagenicity for all compounds in samples from potable water supplies or laboratory studies of DBP formation. Reduction of oxidizing disinfectants is required since these compounds can kill the bacteria or react with the agar, producing chlorinated byproducts. When mutagens are collected by passing potable water through adsorbing resins, active chlorine compounds react with the resin, producing undesirable mutagenic artifacts. The bioanalytical and chemoanalytical needs of drinking water DBP studies required a suitable reductant. Many of the candidate compounds failed to meet those needs, including 2,4-hexadienoic (sorbic) acid, 2,4-pentanedione (acetylacetone), 2-butenoic (crotonic) acid, 2-butenedioic (maleic and fumaric) acids and buten-2-ol (crotyl alcohol). Candidates were rejected if they (1) reacted too slowly with active chlorine, (2) formed mutagenic byproducts, or (3) interfered in the quantitation of known chlorination DBPs. L-Ascorbic acid reacts rapidly and stoichiometrically with active chlorine and has limited interactions with halogenated DBPs. In this work, we found no interference from L-ascorbic acid or its oxidation product (dehydroascorbic acid) in mutagenicity assays of chlorinated NOM using Salmonella typhimurium TA100, with or without metabolic activation (S9). This was demonstrated for both aqueous solutions of chlorinated NOM and concentrates derived from the involatile, ether-extractable chlorinated byproducts of those solutions.     

Mutagenic activity of river water from a river near textile industrial complex in Korea

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.     

Mutagenicity assessment of contaminated soil in the vicinity of industrial area

In the industrial area of Chinhat, Lucknow (India) wastewater coming from pesticide manufacturing and other industries is used to irrigate the agricultural crops. This practice has been polluting the soil and pollutants might reach the food chain. Gas chromatographic analysis revealed the presence of certain organochlorine pesticides in soil samples. Samples were extracted using different solvents, i.e., hexane, acetonitrile, methanol, chloroform, and acetone (all were HPLC-grade, SRL, India). Soil extracts were assayed for mutagenicity using Ames Salmonella/mammalian microsome test. Mutagenicity was observed in the test samples and TA98 was the most responsive strain for all the soil extracts (irrigated with wastewater) in terms of mutagenic index in the presence (+S9) and absence (−S9) of metabolic activation. In terms of slope (m) of linear dose–response curve for the most responsive strain TA98 exhibited highest sensitivity against the soil extracts in the presence and absence of S9 fraction. Hexane-extracted soil sample (wastewater) exhibited maximum mutagenicity in terms of net revertants per gram of soil in the presence and absence of S9 mix as compared to the other soil extracts. Groundwater-irrigated soil extracts displayed low level of mutagenicity as compared to wastewater-irrigated soil. The soil is accumulating a large number of pollutants due to wastewater irrigation and this practice of accumulation has an adverse impact on soil health.     

Effects of residual antibiotics in groundwater on Salmonella typhimurium: changes in antibiotic resistance, in vivo and in vitro pathogenicity

An outbreak-causing strain of Salmonella enterica serovar Typhimurium was exposed to groundwater with residual antibiotics for up to four weeks. Representative concentrations (0.05, 1, and 100 μg L(-1)) of amoxicillin, tetracycline, and a mixture of several other antibiotics (1 μg L(-1) each) were spiked into artificially prepared groundwater (AGW). Antibiotic susceptibility analysis and the virulence response of stressed Salmonella were determined on a weekly basis by using human epithelial cells (HEp2) and soil nematodes (C. elegans). Results have shown that Salmonella typhimurium remains viable for long periods of exposure to antibiotic-supplemented groundwater; however, they failed to cultivate as an indication of a viable but nonculturable state. Prolonged antibiotics exposure did not induce any changes in the antibiotic susceptibility profile of the S. typhimurium strain used in this study. S. typhimurium exposed to 0.05 and 1 μg L(-1) amoxicillin, and 1 μg L(-1) tetracycline showed hyper-virulent profiles in both in vitro and in vivo virulence assays with the HEp2 cells and C. elegans respectively, most evident following 2nd and 3rd weeks of exposure.     

Genotoxicity evaluation of water soil leachates by Ames test, comet assay, and preliminary Tradescantia micronucleus assay

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.     

Polycyclic aromatic hydrocarbon concentrations,mutagenicity, and Microtox® acute toxicity testing of Peruvian crude oil and oil-contaminated water and sediment

The oil industry is a major source of contamination in Peru, and wastewater and sediments containing oil include harmful substances that may have acute and chronic effects. This study determined polycyclic aromatic hydrocarbon (PAH) concentrations by GC/MS, mutagenicity using TA98 and TA100 bacterial strains with and without metabolic activation in the Muta-ChromoPlate? test, and Microtox® 5-min EC₅₀ values of Peruvian crude oil, and water and sediment pore water from the vicinity of San José de Saramuro on the Marañón River and Villa Trompeteros on the Corrientes River in Loreto, Peru. The highest total PAH concentration in both areas was found in water (Saramuro?=?210.15 μg/ml, Trompeteros?=?204.66 μg/ml). Total PAH concentrations in water from San José de Saramuro ranged from 9.90 to 210.15 μg/ml (mean?=?66.48 μg/ml), while sediment pore water concentrations ranged from 2.19 to 70.41 μg/ml (mean?=?24.33 μg/ml). All water samples tested from Saramuro and Trompeteros sites, and one out of four sediment pore water samples from Trompeteros, were found to be mutagenic (P?<?0.001). One sediment pore water sample in Saramuro was determined to have a measurable toxicity (Microtox EC₅₀?=?335.1 mg/l), and in Trompeteros, the EC₅₀ in water and sediment pore water ranged from 25.67 to 133.86 mg/l. Peruvian crude oil was mutagenic using the TA98 strain with metabolic activation, and the EC₅₀ was 17.18 mg/l. The two areas sampled had very high PAH concentrations that were most likely associated with oil activities, but did not lead to acute toxic effects. However, since most of the samples were mutagenic, it is thought that there is a greater potential for chronic effects.     

Comparison of the use of mussels and semipermeable membrane devices for monitoring and assessment of accumulation of mutagenic pollutants in marine environment in combination with a novel microbiological mutagenicity assay

A novel microbiological mutagenicity assay, based on bioluminescence of a marine bacterium Vibrio harveyi mutant strain, potentially suitable for monitoring and assessment of mutagenic pollution of marine environment, has been described recently. Here, we tested the use of this assay, in combination with either mussels (Mytilus sp.) or semipermeable membrane devices (SPMDs), in assessment of accumulation of mutagens in marine water (samples of Baltic Sea water were tested). Either similar results were obtained in both systems or higher signals in the SPMD-based system were detected, depending on the tested water samples. We conclude that the use of both mussels and SPMDs in combination with the V. harveyi bioluminescence mutagenicity assay is a method suitable for monitoring and assessment of accumulation of mutagenic pollutants in marine environment, but in some cases the SPMD-based system may provide a more sensitive test.     

Disinfection by-product formation and mutagenic assay caused by preozonation of groundwater containing bromide

Brominated organic and inorganic by-products are generated during ozonation of groundwater containing high bromide concentrations. This study measured concentrations of bromate, bromoform, bromoacetic acids, bromoacetonitriles, bromoacetone, 2,4-dibromophenol and aldehyde generated by ozonation. The potential mutagenicity of ozonated waters was assessed using the Ames and Microtox tests. Test results for the 18 ozonated groundwater samples demonstrate that bromate formation is associated with high pH, bromide and alkalinity content, low levels of dissolved organic carbon (DOC) and ammonia, and low alkalinity. Brominated organic by-products were correlated with high bromide ion and natural organic matter content, and low ammonia concentrations. The Ames test results demonstrate that all extracts from ozonated water have mutagenic activity; however, the 18 raw groundwater samples had no mutagenicity. The Microtox test results also show that the ozonated water samples were highly toxic. Generally, both bromide and DOC content promoted the formation of ozonation by-products and mutagenicity. Controlling of bromide and DOC concentrations is an effective method of reducing potential by-product formation and eliminating mutagenicity problems associated with groundwater ozonation.