A simple method for the extraction of mutagens from airborne particles

Organic materials were extracted with acetone from filters of airborne particles by soaking, shaking, soxhletion, and sonication. These extracts were tested with and without S9 for mutagenicity using Ames assay and arabinose-resistant assay of Salmonella typhimurium. Among the extraction methods, soaking extract had the highest mutagenic activity followed by sonication, shaking, and soxhletion in both the assays. With the samples studied, it was concluded that soaking with acetone for 1/2 hr is the simplest and an efficient procedure for the extraction of mutagens from airborne particles.Results of cooperative investigation of NIOSH and West Virginia Agricultural and Forstry Experimental Station. Published with the approval of the Director of the West Virginia Agricultural and Forestry Experiment Station as Scientific Paper No. 1822.     

Emission of volatile organic sulfur compounds from a heavily polluted river in Guangzhou, South China

Emissions of five volatile organic sulfur compounds (VOSCs), including methanethiol, carbonyl sulfide, dimethyl sulfide, carbon disulfide, and dimethyl disulfide, from a heavily polluted river, Shijing River in Guangzhou of South China, was studied. The results showed that the amounts of all VOSCs emitted from the river increased from downstream to upstream along the river with increasing magnitude of water pollution. The emission of carbonyl sulfide was the highest among the target analytes, ranging from 23.8 microg m(-2) h(-1) to 42.6 microg m(-2) h(-1) at the water surface of Shijin River. The concentration levels of VOSCs on the riverbank were lower than those at the water surface either in Shijing River or in Liuxi River. However, the contribution of dimethyl disulfide to the total VOSCs on the riverbank was higher than that at the water surface in most sampling sites, indicating that there might be a point source of dimethyl disulfide on the riverbank besides diffusion from water surface. The 24-h semi-continuous monitoring data revealed that the emissions of VOSCs at the water surface peaked at 9:00 and 21:00, which was consistent with the water quality variability in Shijin River caused by daily tidal variation.     

Calculating of river water quality sampling frequency by the analytic hierarchy process (AHP)

River water quality sampling frequency is an important aspect of the river water quality monitoring network. A suitable sampling frequency for each station as well as for the whole network will provide a measure of the real water quality status for the water quality managers as well as the decision makers. The analytic hierarchy process (AHP) is an effective method for decision analysis and calculation of weighting factors based on multiple criteria to solve complicated problems. This study introduces a new procedure to design river water quality sampling frequency by applying the AHP. We introduce and combine weighting factors of variables with the relative weights of stations to select the sampling frequency for each station, monthly and yearly. The new procedure was applied for Jingmei and Xindian rivers, Taipei, Taiwan. The results showed that sampling frequency should be increased at high weighted stations while decreased at low weighted stations. In addition, a detailed monitoring plan for each station and each month could be scheduled from the output results. Finally, the study showed that the AHP is a suitable method to design a system for sampling frequency as it could combine multiple weights and multiple levels for stations and variables to calculate a final weight for stations, variables, and months.     

Use of two population metrics clarifies biodiversity dynamics in large-scale monitoring: the case of trees in Japanese old-growth forests

An alkaline comet assay and a micronucleus test were carried out on erythrocytes of the European chub, Squalius cephalus L., collected in spring and autumn in 2005 and 2006 at three sampling sites in River Sava, near Zagreb, Croatia. The results of comet assay showed the lowest genotoxic influence at the least polluted site, while higher DNA damage was observed at the polluted sites. Although the basal levels of DNA damage were elevated, a clear gradation of DNA damage was found due to pollution intensity in all sampling periods. The lowest cytogenetic damage as revealed by the micronucleus test (MNT) was observed as well at the least polluted site. High variations in MN frequency were observed between sampling periods, although the number of micronucleated erythrocytes was consistently the highest one at the polluted site. The comet assay as a biomarker of genotoxic effect exhibited higher sensitivity in discriminating the genotoxic capacity of studied polluted sites while the MNT was less sensitive. However, both tests should be used together in biomonitoring studies because they can reveal different aspects of DNA damage; comet assay, the early event of genotoxic exposure, and MNT, its final result as a mutagenic potential.     

Design of on-line river water quality monitoring systems using the entropy theory: a case study

The design of a water quality monitoring network is considered as the main component of water quality management including selection of the water quality variables, location of sampling stations and determination of sampling frequencies. In this study, an entropy-based approach is presented for design of an on-line water quality monitoring network for the Karoon River, which is the largest and the most important river in Iran. In the proposed algorithm of design, the number and location of sampling sites and sampling frequencies are determined by minimizing the redundant information, which is quantified using the entropy theory. A water quality simulation model is also used to generate the time series of the concentration of water quality variables at some potential sites along the river. As several water quality variables are usually considered in the design of water quality monitoring networks, the pair-wise comparison is used to combine the spatial and temporal frequencies calculated for each water quality variable. After selecting the sampling frequencies, different components of a comprehensive monitoring system such as data acquisition, transmission and processing are designed for the study area, and technical characteristics of the on-line and off-line monitoring equipment are presented. Finally, the assessment for the human resources needs, as well as training and quality assurance programs are presented considering the existing resources in the study area. The results show that the proposed approach can be effectively used for the optimal design of the river monitoring systems.     

Spatial and seasonal characteristics of river water chemistry in the Taizi River in Northeast China

Anthropogenic activities have led to water quality deterioration in many parts of the world, especially in Northeast China. The current work investigated the spatiotemporal variations of water quality in the Taizi River by multivariate statistical analysis of data from the 67 sampling sites in the mainstream and major tributaries of the river during dry and rainy seasons. One-way analysis of variance indicated that the 20 measured variables (except pH, 5-day biological oxygen demand, permanganate index, and chloride, orthophosphate, and total phosphorus concentrations) showed significant seasonal (p?≤?0.05) and spatial (p?<?0.05) variations among the mainstream and major tributaries of the river. Hierarchical cluster analysis of data from the different seasons classified the mainstream and tributaries of the river into three clusters, namely, less, moderately, and highly polluted clusters. Factor analysis extracted five factors from data in the different seasons, which accounted for the high percentage of the total variance and reflected the integrated characteristics of water chemistry, organic pollution, phosphorous pollution, denitrification effect, and nitrogen pollution. The results indicate that river pollution in Northeast China was mainly from natural and/or anthropogenic sources, e.g., rainfall, domestic wastewater, agricultural runoff, and industrial discharge.     

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.     

Distribution of heavy metals in water and sediments of selected sites of Yamuna river (India)

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.     

Simultaneous determination of 2-phenylbenzotriazole-type mutagens, PBTA-1 through -8, in river water by liquid chromatography-tandem mass spectrometry

We describe a method for the simultaneous determination of eight kinds of phenylbenzotriazole-type mutagens (PBTA-1, -2, -3, -4, -5, -6, -7 and -8) in river water based on liquid chromatography-tandem mass spectrometry (LC/MS/MS). The application of dopant-assisted atmospheric pressure photoionization (APPI) for the detection of the PBTAs was studied. The APPI technique provided higher PBTA signal intensities than those obtained with an electrospray ionization (ESI) source, and the APPI method was used for the determination of the PBTAs. A solid-phase extraction procedure was used for the extractions of PBTA-1 through -8 from river water. The procedure was rapid and the relative standard deviations were below 15%. The detection limits of PBTA-1 through -8 in river water using the proposed method were found to range from 0.04 to 0.5 ng L(-1) and PBTAs were successfully detected in river water at sub-ng L(-1) levels.     

Revising river water quality monitoring networks using discrete entropy theory: the Jajrood River experience

This paper aims at evaluating and revising the spatial and temporal sampling frequencies of the water quality monitoring system of the Jajrood River in the Northern part of Tehran, Iran. This important river system supplies 23% of domestic water demand of the Tehran metropolitan area with population of more than 10 million people. In the proposed methodology, by developing a model for calculating a discrete version of pair-wise spatial information transfer indices (SITIs) for each pair of potential monitoring stations, the pair-wise SITI matrices for all water quality variables are formed. Also, using a similar model, the discrete temporal information transfer indices (TITIs) using the data of the existing monitoring stations are calculated. Then, the curves of the pair-wise SITI versus distance between monitoring stations and TITI versus time lags for all water quality variables are derived. Then, using a group pair-wise comparison matrix, the relative weights of the water quality variables are calculated. In this paper, a micro-genetic-algorithm-based optimization model with the objective of minimizing a weighted average spatial and temporal ITI is developed and for a pre-defined total number of stations, the best combination of monitoring stations is selected. The results show that the existing monitoring system of the Jajrood River should be partially strengthened and in some cases the sampling frequencies should be increased. Based on the results, the proposed approach can be used as an effective tool for evaluating, revising, or redesigning the existing river water quality monitoring systems.     

Monitoring of the three organophosphate esters TBP,TCEP and TBEP in river water and ground water (Oder,Germany)

The behaviour of the three organophosphate esters tributyl phosphate (TBP), tris(2-chloroethyl)phosphate (TCEP) and tris(2-butoxyethyl)phosphate (TBEP) during infiltration of river water to ground water has been investigated. The monitoring site is the Oder River and the adjacent Oderbruch aquifer. From March 2000 to July 2001, 76 ground water samples from monitoring wells located close to the Oder River and nine river water samples were collected. Additionally, influent and effluent samples from local waste water treatment plants, one sample of rain water and samples of roof runoff were collected. All samples were analysed by solid-phase-extraction followed by gas chromatography/mass spectrometry. TBP, TCEP and TBEP were detected at mean values of 622 ng l(-1), 352 ng l(-1), and 2955 ng l(-1), respectively in municipal waste water effluents. This points to a major input of these compounds into the Oder River by municipal waste water discharge. The concentrations of TBP and TBEP decreased downstream the Oder River possibly due to aerobic degradation. TBP, TCEP and TBEP were detected in ground water influenced predominantly by bank-filtered water. This demonstrates a transport of organic compounds by river water infiltration to ground water. TBP, TCEP and TBEP were also detected in rain water precipitation, roof runoff and ground water predominantly influenced by rain water infiltration. This hints to an input of these compounds to ground water by dry and wet deposition after atmospheric transport. Organophosphate esters were also detected in parts of the aquifer at 21 m depth. This demonstrates low anaerobic degradation rates of TBP, TCEP and TBEP.     

Seasonal source influence on river mass flows of benzotriazoles

The anticorrosive agents 1H-benzotriazole (1H-BT), 4-methyl-1H-benzotriazole (4 Me-BT) and 5-methyl-1H-benzotriazole (5 Me-BT), which are usually added to dishwasher detergents, automotive antifreeze formulations and aircraft de-icing/anti-icing fluids (ADAFs), were measured in river water. Samples were collected from 15 sampling sites in the mainstream and selected tributaries of a medium-sized catchment area during summer and winter periods. The aim of this study was to assess a seasonal source influence on mass flows of benzotriazoles (BTs). The study area was representatively selected for an area with a possible influence of airport surface runoff. River discharge measurements were also performed. Moreover, BT concentrations were measured in an anti-icing and a de-icing fluid used at German airports as well as in several dishwasher detergents. The highest concentrations of all three compounds in river water were measured during the winter seasons. The maximum BT mass flows were calculated for all three substances in January when the mean monthly air temperature was the lowest; mass flows were the lowest in July when the mean monthly air temperature was the highest. A significant seasonal influence on BT mass flows in river water was observed for monitoring stations with a possible influence of airport surface runoff and for sampling locations where such an influence could be excluded. This indicates an input of BTs from other temperature-dependent applications, e.g. the use of antifreeze formulations in automotive windscreen wiper or cooling systems. 1H-BT was detected in two dishwasher tablets; 4 Me-BT and 5 Me-BT were not detected. BTs were measured in the anti-icing fluid with concentrations of 715 ng g(-1) (1H-BT), 1425 ng g(-1) (4 Me-BT) and 536 ng g(-1) (5 Me-BT); none of the BTs were detected in the de-icing fluid. Distribution patterns of BTs in ADAF and dishwasher detergents differed from those in river water.     

Occurrence of estrogenic chemicals in South Korean surface waters and municipal wastewaters

Broad scale monitoring of estrogenic compounds was performed at 19 sampling points throughout the Yeongsan and Seomjin river basins and 5 wastewater treatment plants (WWTPs) adjacent to the Gwangju area, Korea, from December 2005 to August 2007. The concentrations of estrogenic compounds, including estrone (E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), bisphenol-A, nonylphenol (NP) and 4-octylphenol (OP), in the samples was measured with gas chromatography/mass spectrometry (GC-MS). In addition, the estrogenic activities throughout the river were investigated using the E-screen assay. Of the six estrogenic chemicals, NP (114.6-336.1 ng L(-1)) and EE2 (0.23-1.90 ng L(-1)) were detected at the highest and lowest levels, respectively in both the river waters and the WWTP effluents. Bisphenol-A showed the largest concentration range, from 7.5 to 335 ng L(-1). The concentrations of E1, E2 and octylphenol ranges were 3.6-69.1, 1.2-10.7, and 2.2-16.9 ng L(-1), respectively. According to the calculated estradiol equivalent concentration (EEQ); however, no estrogenic contribution was observed due to the phenolic compounds in the river waters and effluents. E1 and E2 dominated in both the river water and effluent samples, with contributions to the calculated EEQ of over 79 and 77%, respectively. Conversely, EE2 was rarely detected in the river waters (21%) and effluents (0%). The largest contribution of EE2 to the calculated EEQ was 21% in the river water at S-7. The levels of E1, E2, and EE2 were remarkably decreased in the effluents, indicating that the 5 WWTPs did not contribute to the estrogenic effect of the receiving streams. Overall, the WWTPs did not contributed to the estrogenic activity of the receiving waters, but the livestock industry or wildlife may play an important role in the estrogenic contribution to river water.     

Sandbar-regulated hydrodynamic influences on river hydrochemistry at Mengabang Telipot River, Peninsular Malaysia

Influences of river hydrodynamic behaviours on hydrochemistry (salinity, pH, dissolved oxygen saturations and dissolved phosphorus) were evaluated through high spatial and temporal resolution study of a sandbar-regulated coastal river. River hydrodynamic during sandbar-closed event was characterized by minor dependency on tidal fluctuations, very gradual increase of water level and continual low flow velocity. These hydrodynamic behaviours established a hydrochemistry equilibrium, in which water properties generally were characterized by virtual absence of horizontal gradients while vertical stratifications were significant. In addition, the river was in high trophic status as algae blooms were visible. Conversely, river hydrodynamic in sandbar-opened event was tidal-controlled and showed higher flow velocity. Horizontal gradients of water properties became significant while vertically more homogenised and with lower trophic status. In essence, this study reveals that estuarine sandbar directly regulates river hydrodynamic behaviours which in turn influences river hydrochemistry.     

Occurrence and behaviour of 4-nonylphenol in river water of Germany

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.     

泰东河疏浚工程对通榆河水质的影响

为了解泰东河疏浚工程对通榆河水质的影响,于2012年6月8日、9月12日、12月6日,对泰东河沿线以及通榆河东台段进行调查取样,分析施工期间河体水质变化。结果表明,施工期间水质参数基本保持在Ⅱ~Ⅲ类。根据江苏省水环境监测中心盐城分中心2011年、2013年监测资料评价分析,泰东河河道疏浚后,清理了河床淤泥,提高了泰东河的行洪、抗洪以及通航能力,其水质的好转有效地改善了下游通榆河的水质,确保了饮水安全。     

Design of sampling locations for river water quality monitoring considering seasonal variation of point and diffuse pollution loads

The design of a water quality monitoring network (WQMN) is a complicated decision-making process because each sampling involves high installation, operational, and maintenance costs. Therefore, data with the highest information content should be collected. The effect of seasonal variation in point and diffuse pollution loadings on river water quality may have a significant impact on the optimal selection of sampling locations, but this possible effect has never been addressed in the evaluation and design of monitoring networks. The present study proposes a systematic approach for siting an optimal number and location of river water quality sampling stations based on seasonal or monsoonal variations in both point and diffuse pollution loadings. The proposed approach conceptualizes water quality monitoring as a two-stage process; the first stage of which is to consider all potential water quality sampling sites, selected based on the existing guidelines or frameworks, and the locations of both point and diffuse pollution sources. The monitoring at all sampling sites thus identified should be continued for an adequate period of time to account for the effect of the monsoon season. In the second stage, the monitoring network is then designed separately for monsoon and non-monsoon periods by optimizing the number and locations of sampling sites, using a modified Sanders approach. The impacts of human interventions on the design of the sampling net are quantified geospatially by estimating diffuse pollution loads and verified with land use map. To demonstrate the proposed methodology, the Kali River basin in the western Uttar Pradesh state of India was selected as a study area. The final design suggests consequential pre- and post-monsoonal changes in the location and priority of water quality monitoring stations based on the seasonal variation of point and diffuse pollution loadings.     

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.     

Surface water quality assessment of the Vatinsky Egan River catchment, West Siberia

Stream water chemistry were analyzed across Vatinsky Egan River Catchment (West Siberia). The objective of the study is to reveal the spatial and seasonal variations of the water quality and to assess the anthropogenic chemical inputs into the river system. Stream chemistry were monitored in 24 sampling sites for a period extended from January 2002 to December 2005. Spatial distribution of constituents in the Vatinsky Egan River basin indicated pollution from non-point sources associated with oil development. Data revealed that ion concentrations of river waters are usually negatively correlated with stream discharge. The major spatial variations of the hydrochemistry are related to the salinity. Chloride exhibited wide and high concentration range. A comparison with another rivers of West Siberia reveals that Vatinsky Egan River is the most saline and regional impacts further out in the watershed. The salinity of the river water increases substantially as it crosses Samotlor oil field. Many Cl(-) concentrations in the middle and lower parts of the catchment exceed the world average river values by one or more orders of magnitude. For 38% of sampling events, total petroleum hydrocarbons (TPH) concentrations were above the recommended water quality standards.