中国沿海三省主要饮用水源有机物监测

采用固相萃取、吹扫捕集和气相色谱-质谱联用仪(GC-MS)对江苏、浙江、山东省的21个主要地表饮用水源、126份水样中的25种VOCs、38种SVOCs进行定量检测。结果有19种VOCs、10种SVOCs至少在一个水源地多次被检出,其中挥发性氯代烃、苯系物、氯代苯类、酚类、硝基苯类、酞酸酯类、农药为中国或美国环境保护局提出的"水中优先控制污染物",最高检出量为27.79μg/L。三省主要地表水受到有机物轻度污染,水体中VOCs、SVOCs含量尚未超过《地表水环境质量标准》(GB 3838-2002)和《生活饮用水卫生标准》(GB 5749-2006)限值,工业废水排放及农田雨水径流是地表水有机物的重要来源。     

长江饮用水源地18种挥发性有机物的自动监测应用研究

采用全自动监测系统测定长江饮用水源地中18种挥发性有机物，通过动态吹扫捕集气相色谱法快速分析水中的挥发性有机物（VOCs），18种有机物的方法检出限为0．07～0．50μg／L，在0～20μg／L范围内线性良好，混合标准溶液平行测定的 RSD＜10％，饮用水样品的加标回收率为72．1％～119．4％。同时，探索了4种监测数据质量控制及质量保证的方法，建立了数据评价体系。     

Determination of volatile organic compounds pollution sources in malaysian drinking water using multivariate analysis

A field investigation was conducted at all water treatment plants throughout 11 states and Federal Territory in Peninsular Malaysia. The sampling points in this study include treatment plant operation, service reservoir outlet and auxiliary outlet point at the water pipelines. Analysis was performed by solid phase micro-extraction technique with a 100 μm polydimethylsiloxane fibre using gas chromatography with mass spectrometry detection to analyse 54 volatile organic compounds (VOCs) of different chemical families in drinking water. The concentration of VOCs ranged from undetectable to 230.2 μg/l. Among all of the VOCs species, chloroform has the highest concentration and was detected in all drinking water samples. Average concentrations of total trihalomethanes (THMs) were almost similar among all states which were in the range of 28.4--33.0 μg/l. Apart from THMs, other abundant compounds detected were cis and trans-1,2-dichloroethylene, trichloroethylene, 1,2-dibromoethane, benzene, toluene, ethylbenzene, chlorobenzene, 1,4-dichlorobenzene and 1,2-dichloro - benzene. Principal component analysis (PCA) with the aid of varimax rotation, and parallel factor analysis (PARAFAC) method were used to statistically verify the correlation between VOCs and the source of pollution. The multivariate analysis pointed out that the maintenance of auxiliary pipelines in the distribution systems is vital as it can become significant point source pollution to Malaysian drinking water.     

VOCs在线监测系统与SUMMA罐采样-气质联用法的比对分析

将挥发性有机污染物在线监测系统与实验室内SUMMA罐采样气质联用法(GC-MS)的挥发性有机物分析进行了标准气体和实际空气样品的分析比对,并对偏差原因作分析,提出在线监测系统的维护建议。结果表明,挥发性有机物在线监测系统的监测结果与实验室方法有一定的可比性,可用于大气中挥发性有机污染物的在线监测。     

Investigation and assessment of volatile organic compounds in water sources in China

456 water samples collected from 152 water sources in 2006 were analyzed for 21 volatile organic compounds (VOCs). Concentrations of 21 VOCs ranged from below method detection limits of the laboratory to 7.65 ??g/L (toluene), but seldom exceeded the concentration limits set in the National Drinking Water Quality Standards (GB5749-2006) or the National Environmental Quality Standards for Surface Water (GB3838-2002) of China. Of the 21 individual VOCs analyzed, 11 VOCs were detected in at least one sample at or above 1.0 ??g/L; 6.6% of the water samples had a detection of at least one VOC at or above 1.0 ??g/L, and 2.6% had a detection of at least two VOCs at or above 1.0 ??g/L. Based on the statistical data of detection frequencies above the method detection limits, 75% of the samples detected at least one VOC, and 65% of the samples detected at least two VOCs. Chloroform, toluene, and 1,2-dichloroethene were the three most frequently detected VOCs, with detection frequencies of 76.97%, 68.42%, and 44.08%, respectively. Volatile halogenated hydrocarbons and gasoline components were the two most frequently detected VOC groups.     

水中消毒副产物的监测方法研究进展

含氯、含氧等杀菌类消毒剂在饮用水生产、废水排放、再生水利用等环节应用广泛,会与水中的前驱物通过取代、氧化还原、水解、加成等反应形成种类繁多的消毒副产物(DBPs).DBPs的靶标监测基于已知DBPs的特性如挥发性、半挥发性、不挥发性等,采取相应的前处理和仪器分析方法;非靶标鉴别可对大量未知的DBPs进行筛查.综述了三卤...     

饮用水消毒副产物--卤乙酸的检测

卤乙酸是饮用水氯化消毒中一类主要的消毒副产物,由于存在的广泛性和潜在的健康危害,许多国家和卫生组织相继将其列为饮用水常规监测项目,而我国至今还没有相关规定;为了更好地控制饮用水中卤乙酸的形成,世界各国科研人员先后研究和开发出了性能逐趋完善的多种分析检测方法;本文在国内外文献调研的基础上,对卤乙酸的各种分析检测方法进行了简要的介绍,并指明了今后的发展方向.     

Water quality associated public health risk in Bo, Sierra Leone

Human health depends on reliable access to safe drinking water, but in many developing countries only a limited number of wells and boreholes are available. Many of these water resources are contaminated with biological or chemical pollutants. The goal of this study was to examine water access and quality in urban Bo, Sierra Leone. A health census and community mapping project in one neighborhood in Bo identified the 36 water sources used by the community. A water sample was taken from each water source and tested for a variety of microbiological and physicochemical substances. Only 38.9% of the water sources met World Health Organization (WHO) microbial safety requirements based on fecal coliform levels. Physiochemical analysis indicated that the majority (91.7%) of the water sources met the requirements set by the WHO. In combination, 25% of these water resources met safe drinking water criteria. No variables associated with wells were statistically significant predictors of contamination. This study indicated that fecal contamination is the greatest health risk associated with drinking water. There is a need to raise hygiene awareness and implement inexpensive methods to reduce fecal contamination and improve drinking water safety in Bo, Sierra Leone.     

Comprehensive screening and priority ranking of volatile organic compounds in Daliao River,China

An analytical strategy for comprehensive screening of target and non-target volatile organic compounds (VOCs) in surface water was developed, and it was applied to the analysis of VOCs in water samples from Daliao River. The target VOCs were quantified using purge and trap-gas chromatography-mass spectrometry (P&T-GC/MS). Among 20 water samples, 34 VOCs were detected at least once. For the screening of non-target VOCs, the double distillation apparatus was used for the pre-concentration of VOCs prior to P&T-GC/MS analysis. Subsequently, deconvolution software and NIST mass spectral library were applied for the identification of the non-target compounds. A total of 17 non-target VOCs were identified. The most frequently detected VOCs (detection frequencies >80 %) included toluene, benzene, naphthalene, 1,2-dichloroethane, 1,1,2-trichloroethane, and methyl tert-butyl ether. The distribution of VOCs obviously varied according to the sampling sites. The total concentrations of VOCs in water samples collected from the heavily industrialized cities (Anshan and Liaoyang) and the busy port city (Yingkou) were relatively high. The top ten priority VOCs, including naphthalene, 1,2-dichloroethane, o-xylene, 1,3-dichlorobenzene, tetrachloroethene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, ethylbenzene, m-xylene, and p-xylene, were obtained by the ranking of the detected VOCs according to their occurrence and ecological effects. These compounds should be given more attention in monitoring and drainage control strategies.     

Stabilities of 58 volatile organic compounds in fused-silica-lined and SUMMA polished canisters under various humidified conditions

Fused-silica-lined (FSL) canisters and SUMMA polished (SUMMA) canisters were compared for the recoveries and the stabilities of 58 volatile organic compounds (VOCs) at low ppbv (volume/volume) levels under various humidified conditions using a three-stage preconcentration method followed by GC-MS analysis. The target VOCs included non-polar VOCs (e.g. halogenated hydrocarbons and aromatic hydrocarbons) and polar VOCs (e.g. alcohols, ketones, esters, ethers, nitriles and thiols). The three-stage preconcentration method was initially optimized for simultaneous analysis of non-polar and polar VOCs because determination of canister stability is dependent on the accuracy of analytical measurements. The method showed good linearity over the concentration range from 1 to 25 ppbv for all target analytes, and the correlation coefficients were higher than 0.9974. The method detection limits ranged from 0.023 to 0.39 ppbv. The test mixtures loaded in both type of canisters (n = 3) had concentrations of 1.7-2.5 ppbv per compound at ambient pressure under various humidified conditions (%RH = 1.6, 8.0, 27, 39, 53 and >99% with excess water present). All canister samples were initially analyzed on day 0 (after 6-12 h). The effect of competitive adsorption of water vapor and polar VOCs on active sites of interior surface was remarkably observed for SUMMA canisters. Polar VOCs had a greater requirement for water vapor to be present. The RH percentages that ensured good recovery on day 0 were RH > 8% for non-polar VOCs and RH > 27% for polar VOCs (except alcohols under the condition of RH > 99%). All thiols were not recovered from SUMMA canisters under all conditions. FSL canisters showed good recoveries of more than 86% for all VOCs under all conditions on day 0 (except alcohols under the condition of RH > 99%). The recoveries of alcohols in both canisters under the condition of RH > 99% displayed relatively low recoveries in the range 25-76% because of the partitioning effect into condensed water. The canister samples under the conditions of RH 8.0, 27, 53 and > 99% were analyzed for the stability test on days 3, 7, 14 and 28 after loading. All non-polar VOCs were reasonably stable in the FSL canisters under all examined conditions over 28 days. However, several polar VOCs that have relatively lower vapor pressure, e.g. MIBK, butyl acetate and alcohols except ethanol, showed unstable characteristics under relatively dry conditions (RH 8 and 27%) during 28 days. RH > 53% was needed to ensure good stabilities of all analytes except thiols with the recoveries of > 80% over 28 days for both canisters. Although the FSL canister showed good recoveries of more than 86% for thiols on day 0, drastic degradations were observed after day 3 and they were not detected after day 14.     

Measurement and Interpretation of Concentrations of Urban Atmospheric Organic Compounds

The presence of volatile organic compounds (VOCs) from traffic and other sources in urban areas is a cause for concern about public health. Canister, chemical derivatisation, particulate sampling and adsorption sampling techniques were used to measure VOC concentrations of a wide range of compounds (C6-C40) during a four day campaign in south London with subsequent laboratory analysis of the samples. Compounds quantified included alkanes, mono- and poly-nuclear aromatic hydrocarbons. Also the first sequential measurements of carbonyl compounds (C1-C8) in a UK urban area are presented. Results from canister and adsorption sampling methods are compared. A comparison of the results with other urban data is presented and the temporal variations in VOC concentrations were interpreted with reference to the prevalent wind speeds and directions. The CALINE4 line source dispersion model was generally successful in reproducing the daytime 12 hour average concentrations of selected VOCs.     

A biomaterial based approach for arsenic removal from water

We demonstrate that the non-living, dried roots of the water hyacinth plant [Eichhornia crassipes(Mart.) Solms] can rapidly remove arsenic from water. Atomic absorption spectrometry was used to demonstrate that more than 93% of arsenite (As(iii)) and 95% of arsenate (As(v)) were removed from a solution containing 200 microg As l(-1) within 60 minutes of exposure to a powder produced from dried roots. No difference in removal efficiency was observed between the two oxidation states of As studied. The amount of arsenic remaining in solution was found to be less than 10 microg l(-1) which is the WHO guideline limit value for As in drinking water. The presence of arsenic in drinking water in a number of countries in the developing world has been found to be much higher than the WHO level, affecting the health of millions of people. In this paper, we show that a biomaterial produced from dried water hyacinth roots, a plant that is found in abundant supply in many parts of the world, can provide a simple, effective and yet cheap method for removing arsenic from contaminated water.     

化工企业VOCs治理评估指标体系的建立与应用

在对江苏省化工企业开展挥发性有机物(VOCs)治理核查评估的基础上,采用层次分析(AHP)与模糊综合评价(FCE)相结合的方法,运用化工企业AHP-FCE综合评估模型,建立了包括项目建立、现场排查、评估分析和管理监督4个准则层及22个指标层的化工企业VOCs治理综合评估体系。以江苏某化工园区企业为例,运用建立的指标体系对3家企业进行VOCs治理评估,结果表明,评估结果与企业实际状况相符。提出,VOCs治理评估指标体系的应用,可确定指标权重,解决模糊性问题,减少企业在VOCs整治绩效评估中的主观臆断,具有实际应用价值。     

太湖饮用水源地水环境健康风险评价

介绍了水环境健康风险评价方法,并根据太湖饮用水源地水环境质量监测数据,对4个饮用水源地通过饮水途径引起的水环境健康风险进行了评价。结果表明,2005～2009年,4个饮用水源地水环境健康个人年风险多数超过国际辐射防护委员会(ICRP)推荐的标准,主要风险因子为化学致癌物六价铬和砷;化学致癌物对人体健康危害个人年风险度远高于非化学致癌物;化学致癌物所致健康危害的个人年风险呈波动降低变化,非化学致癌物所致健康危害的个人年风险基本保持稳定。     

某集中式饮用水源地保护区土壤重金属监测与评价

采用现场采样与室内测试方法测定了某大型集中式饮用水源地一级保护区土壤中Cd、Hg、As、Pb、Cr、Cu、Zn和Ni的含量,利用污染指数法、地累积指数法和潜在生态指数法对其土壤环境质量进行了评价。结果表明,上述8种重金属都存在不同程度的超标,其中Cd超标最为严重。地累积指数法评价结果表明,研究区只有Cd、Hg存在一定污染,污染程度分别为中度污染到强污染、中度污染和中度污染到强污染。潜在生态指数法结果表明:研究区土壤样品Cd的单因子潜在生态风险指数最高,轻微、中等和较高风险等级中所占比例分别为44.7%、23.7%、31.6%;其次为Hg,有89.5%的土壤样品中Hg处于轻微生态风险水平,10.5%的土壤样品处于中等生态风险水平;土壤样品中As、Pb、Cu、Ni、Zn、Cr都处于轻微生态风险水平。Cd是研究区最主要的污染和生态风险因子,其次是Hg,说明集中式饮用水源地保护区土壤已受到个别重金属的影响。虽然目前尚不存在饮用水源地水体受污染问题,但应引起高度关注。     

Evaluating the effectiveness of routine water quality monitoring in Miyun reservoir based on geostatistical analysis

This study used geographic information system techniques and geostatistics methods to evaluate the effectiveness of routine water quality monitoring in the western segment of the Miyun reservoir in Beijing. Methodologies as well as the sampling design are evaluated. The single-layer evaluation and three integrated evaluation methods including principal component analysis (PCA), ordinary kriging (OK)_Mean, and Mean_Layers were used to validate the effectiveness of evaluation methods, and the effectiveness of each sampling design was validated by comparing their errors. Results indicated that, while a single-layer evaluation only shows the trophic state of water at a specific level, an integrated evaluation synthetically analyzes and evaluates the trophic state of the entire water body. Furthermore, results of the integrated analysis show that a PCA method is more accurate and can represent the trophic state of the entire water body. The OK_Mean and Mean_Layers methods are only able to represent the mean level for trophic state of the entire water body but cannot reflect local trophic state and distribution details. Although methods used in the routine monitoring of Miyun reservoir have some similarities to the OK_Mean and Mean_Layers methods, their range of errors and uncertainty are greater because of a lack of detailed spatial continuous information. The analysis on the number of sampling points shows that, within a certain range of error, minor changes of sampling points will have no obvious impact on the monitoring results. For the routine monitoring of western Miyun reservoir, using only three to five sampling points for monitoring is inadequate. According to our analysis, it is more appropriate to use at least ten sampling points for monitoring these areas.     

中国环境空气苯系物类挥发性有机物监测能力现状分析

为了解和评价中国环境空气挥发性有机物(VOCs)的监测能力和技术水平,以量化的手段评估环境空气VOCs监测数据质量,促进实验室质量管理水平提升,笔者以环境空气VOCs中的苯系物为代表,组织31个省、自治区、直辖市216家各级各类生态环境检验检测机构开展了实验室比对,利用稳健统计技术分析评价实验结果。结果表明:环境空气苯系物类VOCs比对结果的整体合格率为68.5%,省级站、地市级以上站、社会化检测机构合格率分别为86.7%、75.4%和46.9%。可见现阶段中国环境空气苯系物类VOCs整体检测能力仍有提升的空间,社会化机构的检测技术水平尚待提升。建议地方部门加强对环境空气VOCs监测的技术培训,尽快提高VOCs监测技术水平,保障VOCs监测数据质量,同时强化对社会化检测机构的监督管理,督促其提升服务水平。     

Fluoride contamination in drinking water in rural habitations of Central Rajasthan, India

Fluoride concentration in groundwater sources used as major drinking water source in rural area of block Nawa (Nagaur District), Rajasthan was examined and the toxic effects by intake of excess fluoride on rural habitants were studied. In block 13, habitations (30%) were found to have fluoride concentration more than 1.5 mg/l (viz. maximum desirable limit of Indian drinking water standards IS 10500, 1999). In five habitations (11%), fluoride concentration in groundwater is at toxic level (viz. above 3.0 mg/l). The maximum fluoride concentration in the block is 5.91 mg/l from Sirsi village. As per the desirable and maximum permissible limit for fluoride in drinking water, determined by World Health Organization or by Bureau of Indian Standards, the groundwater of about 13 habitations of the studied sites is unfit for drinking purposes. Due to the higher fluoride level in drinking water, several cases of dental and skeletal fluorosis have appeared at alarming rate in this region. There is an instant need to take ameliorative steps in this region to prevent the population from fluorosis. Groundwater sources of block Nawa can be used for drinking after an effective treatment in absence of other safe source. The evaluation of various defluoridation methods on the basis of social and economical structure of India reveals that the clay pot chip, activated alumina adsorption, and Nalgonda techniques are the most promising.     

Location and Characterization of Emission Sources for Airborne Volatile Organic Compounds Inside a Refinery in Taiwan

This study aimed to locate VOC emission sources and characterized their emitted VOCs. To avoid interferences from vehicle exhaust, all sampling sites were positioned inside the refinery. Samples, taken with canisters, were analyzed by GC–MS according to TO-14 method. The survey period extended from Febrary 2004 to December 2004, sampling twice per season. To interpret a large number of VOC data was a rather difficult task. This study featured using ordinary application software, Excel and Surfer, instead of expensive one like GIS, to overcome it. Consolidating data into a database on Excel facilitated retrieval, statistical analysis and presentation in the form of either table or graph. The cross analysis of the data suggested that the abundant VOCs were alkanes, alkenes, aromatics and cyclic HCs. Emission sources were located by mapping the concentration distribution of these four types of VOCs in terms of contour maps on Surfer. During eight surveys, five emission sources were located and their VOCs were characterized.     

便携式GC-MS在应急监测中的应用

建立了便携式GC-MS测定空气和水体中挥发性有机物(VOCs)的方法,能快速、有效地对空气中37种和水体中54种挥发性有机物进行现场定性和定量。具有相关性好、检出限低、精密度好、准确度高的特点,适用于空气和水体中挥发性有机物的应急监测工作。