Mutagenic activity in organic concentrate from nishitakase river water in Kyoto City,and its fractions separated by using liquid-liquid fractionation and thin layer chromatography

XAD adsorption followed by elution with ethyl ether was used for recovering mutagenic substances from Nishitakase River water in Kyoto City. XAD extract recovered was separated by acid-base-neutral fractionation and tested for mutagenicity by using TA 1538 as a tester strain. The XAD extract showed strong mutagenic activity in the presence of S-9 mix, indicating the presence of frameshift type promutagens in the river water. Of the fractions separated, the neutral and basic fraction exhibited much more pronounced mutagenic activity and their contribution accounted for 98% of the mutagenic activity of the XAD extract. In order to separate mutagenic components, these active fractions were submitted to thin layer chromatography (TLC). In total 14 TLC subfractions, which had the ability to induce more than 100 net revertants/100μg of the neutral fraction or 10μg of the basic fraction, were isolated after 2 consecutive thin layer chromatographies. In this paper, the importance of varying S-9 concentration in the S-9 mix is also discussed to determine the presence or absence of synergical/antagonistic effect of chemical constituents of complex mixtures like the XAD extract.     

Removal of mutagens from drinking water by granular activated carbon. Evaluation using bacterial mutagenicity tests

The performance of a full-scale granular activated carbon (GAC) treatment system in removing mutagens from drinking water obtained from the Ohio River has been evaluated using two bacterial mutagenicity tests. The Salmonella/microsome assay (Ames Test) and a fluctuation assay were both performed using Salmonella typhimurium strains TA98 and TA100. Influent and effluent waters were collected at two GAC adsorbers, one filled with virgin GAC and one with nearly exhausted GAC. The samples were submitted to reverse osmosis (RO) pre-concentration, sequential liquid-liquid extractions and XAD-2 resin adsorption. The RO aqueous concentrations of both influents gave positive mutagenic responses with both strains in the fluctuation assay but no activity in the Ames test. The extracts and adsorbates showed mutagenic responses in the Ames test with both strains, the highest values being observed with TA100 in the absence of metabolic activation. The summation of mutagenic activity on the basis of net revertants per liter indicated that exhausted GAC removed a substantial fraction (more than 85%) of the mutagenic activity whereas virtually complete removal was observed with virgin GAC. These data suggest that short-term mutagenicity tests may be useful in evaluating the performance of GAC or other adsorbents used in the treatment of drinking water.     

Mutagenic assessment of Prestige fuel oil spilled on the shore and submitted to field trials of bioremediation

The mutagenicy of the slightly weathered fuel oil from the Prestige oil spill and the effects of different bioremediation products (nutrients and/or microorganisms and biodiesel) on the potential mutagenic activity of this heavy fuel oil spilled on the shore were evaluated for a period of 1 year using the Ames Salmonella assay with strains TA98, TA100, TA1535 and TA1537 in the absence and presence of exogenous metabolic activation (S9 fraction from rat liver). The in situ bioremediation experiment was performed using tiles located in the supra-littoral and intertidal zones of a beach seriously affected by the fuel oil spill. The results obtained showed the mutagenic activity of the slightly weathered fuel oil extracts at the beginning of the experiment in strain TA98 that persisted for more than 150 days in both the untreated control and treated tiles independently of the zone of the beach considered. However, after 360 days neither the control nor the treated tiles in the intertidal zone showed mutagenic activity and a weak positive response in strain TA98 was detected for the control fuel oil extracts from supra-littoral tiles. The application of biodiesel to accelerate the biodegradation of this type of fuel oil may constitute a further genotoxic hazard to the environment, since the mutagenic response achieved from the biodiesel-fuel oil mixture in the first samplings (days 0 and 30) was more potent than that obtained from the control tiles. The mutagenic activity was detected along the study with S. typhimurium TA98 in both the presence and absence of S9 microsomal fraction, but the addition of S9 fraction in the assay always increased the number of revertants induced. In general, these findings suggest that the bioremediation strategies used were not effective in eliminating the genotoxic hazard associated with this heavy fuel oil attached to rocky substrate since they did not achieve a decrease in the mutagenic response with respect to the untreated control tiles. These data also confirm that genotoxicity assays should be used to evaluate the effectiveness of bioremediation efforts associated with oil spills for a better risk assessment.     

Studies on the toxicity of pulp and paper mill effluents—I. Mutagenicity of the sediment samples derived from Kraft paper mills

Sediment samples collected at three different coastal points (Shinguu, Ooigawa and Tagonoura) were extracted with diethylether and then methanol. Each extract was separated into five fractions by high-speed liquid chromatography and they were submitted to mutagenic assay using B. subtilis and S. typhimurium and to GC-MS analysis.The ether fraction of sediment sample from Shinguu showed DNA damaging potency on B. subtilis and exhibited mutagenic effect on S. typhimurium TA 98, TA 100 and TA 1537. 2,4,6-Trichlorophenol, 3,4,5,6-tetrachloroguaiacol, dehydroabietic acid, pyrene and fluoranthene were mutagenic substances among 28 substances identified and tested.     

Studies on the toxicity of pulp and paper mill effluents—II. Mutagenicity of the extracts of the liver from spotted sea trout (Nibea mitsukurii)

Sediment samples collected at three different coastal points (Shinguu, Ooigawa and Tagonoura) were extracted with diethylether and then methanol. Each extract was separated into five fractions by high-speed liquid chromatography and they were submitted to mutagenic assay using B. subtilis and S. typhimurium and to GC-MS analysis.The ether fraction of sediment sample from Shinguu showed DNA damaging potency on B. subtilis and exhibited mutagenic effect on S. typhimurium TA 98, TA 100 and TA 1537. 2,4,6-Trichlorophenol, 3,4,5,6-tetrachloroguaiacol, dehydroabietic acid, pyrene and fluoranthene were mutagenic substances among 28 substances identified and tested.     

Mutagenic activity in humic water and alum flocculated humic water treated with alternative disinfectants

Mutagenic activity in Salmonella typhimurium strains TA 100 , TA 98 and TA 97 has been determined for humic water and alum flocculated humic water, treated with the alternative disinfectants chlorine, ozone, chlorine dioxide, ozone/chlorine and chlorine/chlorine dioxide.The most pronounced activity was found for chlorine treated water tested on strain TA 100 without metabolic activation (S9 mix). Ozone treatment prior to chlorination did not alter the activity, while treatment with chlorine in combination with chlorine dioxide reduced the activity to a level somewhat over the background. No mutagenic response was detected in waters treated with ozone or chlorine dioxide alone. In presence of S9 mix all water extracts studied were non-mutagenic.     

Mutagenicity of three agricultural soils

A chemical and biological testing protocol was employed to evaluate the mutagenic potential of the organic compounds extracted from three agricultural soils. The analytical procedures used included bioassays with Salmonella typhimurium and Aspergillus nidulans for the detection of point mutations and a gas chromatography/mass spectrometry/computer system to identify major organic constituents. The extracts of all three soils exhibited mutagenic response in the bioassays. At a dose level of 1000 micrograms per plate, the organic extract of the Bastrop clay induced 434 net revertants; while at the same dose level the Norwood sandy clay and the Sassafrass sandy loam induced 35 and 178 net revertants, respectively, in the Salmonella assay with metabolic activation. In the Aspergillus assay, the extract of the Norwood and Bastrop soils induced a positive response without metabolic activation; this effect was reduced or eliminated in the presence of metabolic activation. Chemical analysis identified a variety of initiators, promotors, inhibitors, and cocarcinogens; however, there were no mutagenic compounds identified in any of the soil extracts. The results of this combined testing protocol indicate that the agricultural soils tested had an inherent level of mutagenic activity, which was not detected by GC/MS analysis alone, and this activity may be related to the past history of agricultural practices, including biocide applications, fertilization, and cultivation.     

重庆五座水厂水的有机物致突变活性比较

采用固相萃取技术（GDX-120大孔树脂）于春、夏、冬季对以嘉陵江为水源的A厂和B厂，以长江为源的C厂和D厂以及以两江汇水为水源的E厂提取进厂水和出厂水中的有机物，以Ames试验评估其致突变活性。结果表明：①现行水处理工艺在低温季节及源水污染较为严重的情况下可降低出厂水的致突变活性，而在高温季节及源水污染不太严重的情况下可导致出厂水的致突变活性升高；②以嘉陵江为水源的水厂出水致突变危害均高于以长江为水源的水厂出水；③水中有机物的致突变活性以移码型为主，TA98是测试的敏感菌株。     

Mutagenic potential of laboratory chlorinated river water

Sample water was taken from a river and chlorinated at a concentration of 5 mg 1(-1) chlorine for 20 h in the laboratory in order to examine the effect of chlorination on the mutagenic potential of organic extracts that were recovered using XAD-2 resin and diethyl ether. It was found that the XAD extracts recovered from the river water showed per se strong mutagenic activity, in the presence of S-9 mix, towards Salmonella typhimurium TA 1538. When the mutagenic activity of the XAD extracts was related to the initial water volume, chlorination increased both the direct-acting and the S-9 dependent mutagenic activity. This suggests that chlorination produced de novo direct-acting and S-9 dependent mutagens and/or increased pre-existing mutagenic activities. In addition, in this study XAD extracts recovered from chlorinated and unchlorinated river water were divided into a neutral, basic and acidic fraction respectively. When the mutagenic activity of each fraction was related to the initial water volume, the neutral fraction showed the most marked increase in mutagenic activity with, and without, the S-9 mix in the chlorinated river water.     

Genotoxic response of Austrian groundwater samples treated under standardized UV (254 nm)--disinfection conditions in a combination of three different bioassays

Ground water samples from different geographic areas in Austria, with different amounts of natural and anthropogenic organic compounds were treated with a standardized low pressure UV (254 nm)-irradiation laboratory flow-through system (UV fluence: 800 J/m2). The genotoxic activities of the water samples before and after the UV disinfection were investigated using a combination of three different bioassays which complement each other with regard to their sensitivity detecting different genotoxins. The test battery comprises the Salmonella/microsome assay (Ames test with TA98. TA 100 and TA 102, with and without S9 mix) and two micronucleus tests with the plant Tradescantia (clone #4430) and with primary rat hepatocytes. Overall, the tested Austrian groundwater samples used for human consumption caused only weak genotoxic activities compared to drinking water samples reported from other countries under similar experimental conditions. With the exception of one weak positive result in the Ames test (only in strain TA98 without S9 mix) with an induction factor of 1.9) all samples after UV disinfection were devoid of additional mutagenic and clastogenic activities compared to the samples before UV disinfection.     

Progress in the isolation and characterization of non-volatile mutagens in a drinking-water

Using the Ames Salmonella mutagenicity test (TA98, without S9), non-volatile mutagenic fractions were obtained by applying a separation scheme on XAD extracts of Pretoria drinking-water. The fractionations obtained were based on solubility, volatility, permeation and adsorption and the mutagenicity yield of each step was estimated. One mutagenic fractionconsisted of humic like material, possibly together with polar polynuclear aromatic hydrocarbons.     

Mutagenic activity in drinking water prepared from groundwater: a survey of ten cities in The Netherlands

A survey of the mutagenic activity (Ames Salmonella/microsome assay) in drinking water prepared from groundwater in 10 cities of The Netherlands is presented. Mutagenic activity with strain TA98 with S-9 mix was found in the drinking water of six cities. There are strong indications that this mutagenic activity is caused by organics of natural origin. In the drinking water of three cities, trichloroethane, trichloroethene and tetrachloroethene were detected, which indicates that in these water-catchment areas organic pollutants have reached groundwater.     

Evaluation of extracellular products and mutagenicity in cyanobacteria cultures separated from a eutrophic reservoir

The algal extracellular products (ECPs) in three cultures of cyanobacteria species (Anabaena, Microcystis, and Oscillatoria) dominating the eutrophic reservoir populations and their toxins have been investigated in the present work. Using gas chromatography coupled with high-resolution electron-impact mass spectrometry (GC/EI-MS) and high performance anion-exchange chromatography (HPAEC) techniques, more than 20 compounds were found in the algal culture (including cells and filtrates) extracts. The main identified ECPs were classified to polysaccharides, hydrocarbons, and aldehydes. Odor causing substances such as trans-1,10-dimethyl-trans-9-decalol (geosmin) and 2-methylisoborneol (2-MIB)were also found in the algal cultures. The potential mutagenicity of the algal suspensions was also studied with the Ames test. The organic extracts of the algal suspension from the axenic cultures were mutagenicity in TA98 without S9 mix and in TA100 with and without S9 mix. The results indicate that the ECPs of three algae species dominating the eutrophic reservoir were mutagenic clearly in the bacterial test.     

Mutagenic and clastogenic effects of organic extracts from the Athenian drinking water

Organic extracts of chlorinated drinking water collected from the water distribution system of Athens, Greece, were tested in parallel for their ability to cause mutations in the Salmonella His+ reversion system and sister chromatid exchanges (SCE) and chromosomal aberrations in CHO cells. They were found to induce His+ revertants in frequencies similar to those detected previously with drinking water extracts from other areas around the world. We observe that organic samples from surface drinking water induce SCE and chromatid type abnormalities in CHO cell cultures while samples collected from ground drinking water did not. These findings confirm that chlorinated surface drinking water contains substances which are mutagenic and clastogenic and may be carcinogenic in humans.     

Microscale fluctuation assay coupled with Sep-PakR concentration as a rapid and sensitive method for screening mutagens in drinking water

A sensitive short-term mutagenicity test, the microscale fluctuation test has been coupled with a concentration method based on adsorption on Sep-Pak^R C₁₈ cartridges as a method for screening drinking water mutagens. Comparison with XAD-2 concentration method showed that Sep-Pak adsorbed 5 times higher quantity of organics but was slightly less efficient for adsorbing TOX.Microscale fluctuation test was found to be more sensitive than Ames test by testing known direct-acting mutagens and concentrates of drinking water. Samples derived from conventional treatment including chlorination from eight surface water supplies in Norway were concentrated at pH 2 by adsorption on the disposable columns. The adsorbates were tested at different doses by the microscale fluctuation assay. The mutagenic properties of drinking water samples were also related to total organic carbon (TOC), total organic halogen (TOX) and trihalomethanes (THM) concentrations. Dose-related mutagenic responses were found for all the samples with S. typhimurium TA 100 and TA98 strains without metabolic activation. Good relationship was found between mutagenicity data and TOX and THM results. The method showed to be simple, rapid and suitable for routine screening of mutagens in drinking water.     

Influence of ozonation on the in vitro mutagenic and toxic potential of secondary effluents

Reclamation of municipal effluents by advanced treatment processes is an attractive perspective for facing certain water shortage problems. However, the application of tertiary techniques should be thoroughly examined for their potential hazardous effects. Ozonation is an efficient chemical oxidation method, often used in wastewater reclamation, which may result in by-products that may alter the toxic and mutagenic properties of effluents. In this study, Ames test and Microtox test were used for the evaluation of ozonation efficiency to upgrade secondary effluents quality. In general, the toxic response and mutagenic effect without metabolic activation of test species were influenced mainly by the ozone dose and ozonation duration, whereas the mutagenic effect with metabolic activation was influenced mainly by ozone dose, indicating that ozone conditions strongly affect the formation of by-products. In most cases, the toxicity was increased and reached up to 100% (in relation to that of secondary effluent) after ozonation with 8.0 mg O₃/L for 5 min. On the contrary, in most cases the mutagenic activity towards strain TA98 without metabolic activation was reduced, when ozone dose and contact time increased. However, the mutagenicity was also increased after ozonation at low ozone doses and for contact times less than 5 min. The mutagenic activity of treated effluents towards strain TA98 with metabolic activation remained about the same or was reduced, compared to that of secondary effluent, and was even eliminated after ozonation with 8.0 mg O₃/L for contact times higher than 5 min.     

焚烧飞灰颗粒对沥青混合料水稳定性的影响

为了实现焚烧飞灰(IFA)在沥青路面中的资源转化,将焚烧飞灰与水泥造粒以及与水泥、硅灰、粉煤灰造粒,研究掺有造粒颗粒沥青混合料的水稳定性以及冻融劈裂试验条件对其水稳定性的影响机制.结果 表明:焚烧飞灰造粒后,氯离子浸出率分别降低了56.76％、59.12％;冻融劈裂试验条件对焚烧飞灰/水泥颗粒沥青混合料水稳定性影响顺序为抽真空过程>冷冻过程>击实次数,抽真空过程破坏造粒颗粒表面沥青膜,导致可溶氯盐溶出,氯盐溶液在冻融过程中产生的冻胀、盐胀与腐蚀综合作用是导致沥青混合料内部结构受损关键因素;焚烧飞灰与水泥、硅灰、粉煤灰造粒的方法能有效改善沥青混合料的水稳定性.     

Chemical characteristics and mutagenic activity of PM10 in Torino, a northern Italian city

Epidemiological studies of particulate matter (PM) have associated PM mass, as well as certain individual components of PM such as secondary particulate with adverse human health effects. For example genotoxic effects attributed to PM may relate to the content of organic compounds but also to the oxidative DNA damage generated by transition metals like iron. However the exact physiochemical mechanism by which PM produces adverse effects is not clear. The aims of this study were to evaluate (1) concentrations of PM10, (2) amounts of bioavailable iron associated with PM10, (3) amounts of secondary particulate expressed as SO4(=) and NO3(-) and (4) the mutagenic activities of PM10 organic extracts. Sampling was carried out in a meteochemical station located in Torino, a northern Italian city with high levels of PM10. The mean PM10 concentration in the considered period was 46.1+/-28.8 microg/m3, the iron mean concentration was 0.83 microg/m3 (+/-0.65 microg/m3) and the bioavailable Fe was 5.7% (+/-4.4%). The data showed that secondary particulate matter (as sum of sulfates and nitrates) constituted about 47% of PM10 total mass. Both iron and secondary species concentrations were positively associated with PM10 levels. Seasonal variations of PM10 concentration, iron level and secondary species amount were significant. Samples were tested for mutagenicity with Salmonella typhimurium strains TA98 and TA100, with and without metabolic activation and a positive response was observed especially for TA98. There were positive statistical associations between mutagenicity and PM10, bioavailable iron, sulfates and nitrates concentrations. Therefore, these results showed the usefulness of this biological approach for monitoring PM10.     

Characteristics of municipal solid wastes incineration (MSWI) fly ash–cement matrices and effect of mineral admixtures on composite system

An experimental work was carried out to investigate the feasibility of application of MSWI fly ash as an auxiliary cementitious material. The water demand for normal consistency, setting time, volume stability, flexural and compressive strength of MSWI fly ash–cement compound matrices were tested. And, the composite effect and the influence of mechanical properties and heavy metals solidification are studied by mixing MSWI fly ash–cement matrices with common mineral admixtures. The results show that the MSWI fly ash has some cementitious activity, but the reactivity is relatively lower and its addition to cement may lead to retardation of cement hydration. After incorporation of common mineral admixtures, the strength of solidified body was enhanced, and the effect of the heavy metals-immobilizing may be reinforced.     

The quality of drinking water prepared from bank-filtered river water in the Netherlands

The quality of raw water and drinking water was analysed at 18 sites in the Rhine delta in an integrated program with hydrological,chemical and toxicological parameters. About 600 different organic compounds have been detected,of which about 200 could be identified,and 400 more have been classified on the basis of their mass spectra. Lipophilic compounds with a log P(octanol/water) greater than 3.2 are adsorbed during the first few meters of the bank infiltration. More hydrophilic compounds are often not adsorbed and not removed by the currently used water purification systems,such as aeration and sand filtration.The presence of organohalogens was demonstrated with surrogate parameters,such as extractable and adsorbable organohalogen. All the samples tested were mutagenic in the Ames test with strain TA98 + S9 mix. Only part of the mutagenic activity was related to compounds originating from Rhine water.