A novel method for evaluating bioavailability of polycyclic aromatic hydrocarbons in sediments of an urban stream.

Hydrophobic organic pollutants in urban wet weather discharges can accumulate in the sediments of receiving waters and may have adverse effects on the ecological system, especially on benthic organisms. Here, a novel method is developed for evaluating the bioavailability of such hydrophobic organic pollutants by considering the digestive guts in deposit-feeding polychaetes. We compared the amount of polycyclic aromatic hydrocarbons (PAHs) extracted by an organic solvent and by sodium dodecyl sulfate (SDS) solution (as a hypothetical digestive gut fluid of polychaetes) and interpreted the ratio of the two values as bioavailability. The sediment extracts were applied to bacterial acute toxicity tests and algal growth inhibition tests. Sediment samples were collected from an urban stream system receiving wet weather discharges. The bioavailability of the total amount of 12 PAHs in the sediments was in the range 14-38% based on the results from the GC/MS determination of the two different extracts. Lower molecular PAHs showed higher bioavailability compared to the higher molecular ones. The sediment extracts were shown to be toxic towards both algae and bacteria. The SDS extracts showed similar or higher toxicity in the two biotests compared to the organic solvent extracts in spite of their lower PAHs content.     

Persistent pollutants urban rivers sediment survey: implications for pollution control.

The impacts of diffuse urban sources of pollution on watercourses are quantified. A survey of nine urban streams in Scotland for persistent pollutants in stream sediments is described, together with sediments from SUDS ponds. Determinands reported are: PAHs, total hydrocarbons, and toxic metals (As, Zn, Ni, Pb, Cu, Cr, Cd). Results highlight hydrocarbons as a major urban pollutant, and show significant sediment contamination by toxic metals. The metals that occurred in the highest concentrations varied across the nine streams, but Pb, Cr, Ni, Zn and Cu most frequently present exceeded sediment quality standards. The pattern of contamination by PAHs suggested that pyrolytic sources were more ubiquitous and present in greater quantities than oil spill sources in these urban catchments. Exceptions were the sites below industrial estates. The findings indicate that four levels of activity will be needed to control urban diffuse sources of pollution: reductions in quantities of toxic pollutants used by manufacturers in the motor and construction industries; housekeeping measures to minimise storage and handling risks for oil and chemicals; public engagement to minimise polluting activities such as dumping oil and chemicals, and private car use; use of SUDS technology, including retro-fits in the worst affected urban areas.     

The organic contamination survey and health risk assessment of 16 source water reservoirs in Haihe River basin

Although contamination by organic pollutants has previously been reported to occur in the Haihe River basin, few studies have been carried out on the levels of source water reservoir contamination and the health risk in the Haihe River basin. To understand the organic pollution status of the reservoirs in the Haihe River basin, samples were collected from 16 source water reservoirs. The samples were analyzed for the representative organic pollutants, which included benzene homologues, chlorobenzene compounds, organophosphorus pesticides, and nitrobenzene compounds, a total in all of 17 compounds. It was observed that the concentrations of the 17 compounds in the 16 reservoirs were all less than the limit laid down by Chinese surface water quality standards. In addition, benzene, toluene, nitrobenzene, p-nitrochlorobenzene, 2,4-dinitrotoluene and 2,4-dinitrochlorobenzene, dichlorvos, demeton, dimethoate methyl parathion, malathion and parathion were frequently detected in the 16 source water reservoirs, especially the organophosphorus pesticides; the detection rates of dichlorvos, dimethoate, methyl parathion, malathion and parathion were all 100% in the 16 source water reservoirs. The detection rate of target compounds suggested that organic pollution had been common in the source water of the Haihe River basin. The health risk assessment results suggested that the noncarcinogenic risk hazard quotient values of the target compounds were less than one, and the cancer risk values were all below 1 × 10(-6), which indicated that the heath risk produced by the target compounds in the 16 reservoirs was at an acceptable level.     

黄河重点河段水环境有毒有机物污染现状浅析

以黄河水污染重点研究河段和来水相关区的中游干流、支流较大区间为调查对象,开展了有毒有机物的专项筛选和重点识别工作。对13个地表水断面、11个底质测点样品进行了GC MS联机分析。结果表明,研究河段不但有毒有机物的种类繁多,包括了酞酸酯类、酚类、氯苯类、多环芳烃类等多种类型的有毒有机物,而且有毒有机污染状况较严重,酞酸酯类是调查中峰值最高的一类有毒有机物。同时对特征有毒有机物提出了控制对策建议。     

Monitoring of Trace Organic Contaminants in Atmospheric Precipitation

The design and use of a year-round sampler for trace organic contaminants in wet precipitation are described. The sampler is electronically controlled and features a 0.25-meter-square stainless steel funnel with a 4-L amber glass bottle. The whole assembly is insulated and equipped with heating elements which permit collection of ice/snow samples. The samples are preserved in situ with methylene chloride and extracted again with methylene chloride in the laboratory. A small network of four sampling stations was established in the Great Lakes basin for the purpose of obtaining a refined estimate of atmospheric loading of trace organic pollutants to the Great Lakes. A total of 93 rain/snow samples was collected from the network during 1986. These samples were analyzed for organochlorine pesticides, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. The most significant organochlorine pesticides found were alpha-HCH, gamma-HCH (lindane), and methoxychlor with concentrations in the range of 7–10 ng/L, 4–5 ng/L, and 2–7 ng/L, respectively. Other organochlorinated pesticides were measured occasionally at sub-nanogram levels. Polychlorinated biphenyls were also widely detected with mean concentrations of 7–10 ng/L. Polycyclic aromatic hydrocarbons were detected in about 50% of the samples. Some of the prevalent polycyclic aromatic hydrocarbons were phenanthrene, methylnapthalene, fluoranthene, and pyrene with mean concentrations of 50–200 ng/L. Deposition of agricultural chemicals (HCHs) was higher in Lake Superior and Huron but precipitation at Lake Erie and Lake Ontario contained more varieties of domestic pesticides.     

Water quality criteria for total suspended solids (TSS) in urban wet-weather discharges.

Total suspended solids (TSS) from combined sewer overflows (CSOs) and stormwater discharges represent a crucial parameter for evaluating wet-weather pollution in urban areas. In fact, the increase of TSS in water during rain events can have ecotoxic effects on aquatic organisms. Furthermore, major potentially harmful substances such as heavy metals, PAHs and organic matter are adsorbed onto TSS and later settle on sediment. Water quality criteria for TSS consequently enable the risk of wet-weather pollution to be assessed, for instance to avoid detrimental effects on aquatic organisms. The criteria proposed in this study cover the short-term impact of TSS on fish (acute quality criteria AQC), taking into account the duration of their exposure in the receiving water. The concentration-exposure duration-effect curve proposed here thus predicts "ill effects" on fish for different exposure times and TSS concentrations. The ecotoxic effects of adsorbed pollutants are also taken into account with an additional safety factor. We implement this TSS criteria in a software that allows us to estimate the number of rain events that exceed a given morbidity threshold for fishes per year.     

吉林市排污河底泥的污染状况及其生态风险评价

以吉林市排污河中底泥为主要研究对象,布置12个监测断面35个代表性采样点,采集并分析了河道内底泥样品中8种重金属及16种USEPA优先控制的多环芳烃的含量,并分别采用地质累积指数法(I_(geo))、潜在生态风险评价法(PERI)、沉积物质量基准法(SQGs)对排污河底泥中污染物进行了生态风险评价。结果表明,该排污河底泥中重金属及多环芳烃均不同程度超过松花江水系沉积物背景值,其中Hg、Pb、Cu、As、NAP、ANT超标倍数分别为87.5、10.2、6.18、5.90、115.6和228.5;I_(geo)显示Hg的生态风险最大,I_(geo)达到了5.82,而Cd和Ni的风险较小,这与PERI中Hg风险最大的结果一致;SQGs评价结果表明由重金属及多环芳烃引起的污染会产生生物毒性,且不利生物毒性将频繁发生;(3)以上结果说明,该排污河呈现以Hg为主要风险因子的重金属与多环芳烃复合污染现象,在今后应加强底泥监测和定期清淤,从而推动区域生态环境的治理与恢复。     

Fractioning of petroleum hydrocarbons from seeped oil as a factor of purity preservation of water in Lake Baikal (Russia)

Polycyclic aromatic hydrocarbons (PAHs) and n-alkanes were found in five different types of oil-containing samples emanating from deep oil seeps in Lake Baikal, the deepest and oldest lake in the world containing 20% of the world’s surface freshwater. The n-alkanes were the dominant component of the seeped oil on the water surface. PAHs were minor compounds of the oil, but this group is included in a priority series of organic contaminants that are subject to environmental regulation. The set of studied samples from the seep included: (i) freshly-emitted oil on the lake surface, (ii) oil at the lake bottom, (iii) samples of asphalt towers at the lake bottom, (iv) oil from voids within the sediment core and (v) samples of water from different depths. High variability in the concentrations of n-alkanes and PAHs suggested the presence of oil fractionation at the sediment-water interface. A light fraction of oil enriched by n-alkanes migrates to the surface of the lake’s water column, where n-alkanes are biodegraded by the Baikal microbial community while heavy oil fractions remain at the lake bottom and form asphalt towers in which PAHs with maximum toxicity accumulate. In the lake’s photic water layer, PAHs from light oil can be accumulated by phytoplankton. In the lake’s water column, benzo[a]pyrene was not detected over their detection limit (0.1 ng/L). The Toxic Equivalent (TEQ) value of PAHs identified in the Baikal water ranged from 0.001 to 0.012 ng/L.     

长江中游岸线水域典型污染物种类与来源解析

以长江中游宜昌段、武汉段和黄石段3个监测断面为研究对象,选取农业渔业、工业生产、港口物流、过江交通和城镇生活共5种典型开发类型岸线,鉴别了不同开发类型岸线水域主要污染物种类,同时解析了其时空分布状况.结果 表明,依据《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),...     

天津滞缓流型城市河网水质时空分布特征

针对天津城市河网滞缓流特点突出、水质变化与天然河流不同的特征,以海河、津河、卫津河、外环河4条重点河道为研究对象,应用聚类分析、因子分析、多元线性回归分析等多元统计分析方法对11个重点河道断面2008年和2009年39周的水质监测指标进行了分析。结果表明:河道断面水质在时间和空间上具有一定的分布特征,时间上,各断面5—8月水质较其他时间更差,氨氮、总磷超标严重;空间上,呈现出从海河到津河、卫津河再到外环河水质逐步下降的特征;海河、津河、卫津河等河道氮磷类汇入是主要污染源,外环河则以有机物污染汇入为主要污染源。     

拜泉镇城区地下水化学特征分析

拜泉镇区内地下水可划分为第四系松散岩类孔隙潜水和白垩系碎屑岩类孔隙-裂隙承压水两大类型,共采集了11个无机全分析水样(潜水水样点4个,承压水点7个)和4个有机分析水样(均为承压水)。潜水水化学类型以HCO3-C l为主,而承压水水化学类型则以HCO3型水。城区潜水可C l-、NO3-、NO2-、Mn2+、NH4+、TDS、总硬度等指标均超标,而承压水只有Mn2+、NH4+超标,且超标程度低于潜水。可见,研究区潜水的水质已经受到人类生活生产的污染,水质较承压水差。虽然,目前研究区承压地下水所测试的有机物含量均没有超过饮用水标准的限值,但4个地下水样中均检出农药成分"666",这说明了研究区承压水均受到了人类农业生产中使用农药的污染。     

Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility test.

An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road dust, into benthic organisms living in a receiving water body. The road dust is supposed to be urban runoff particles under wet weather conditions. Sodium dodecyl sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were the main PAH species in the SDS extractable fraction of road dust, as well as the whole extract. Benzo(ghi)perylene showed relatively low concentrations in the SDS extract in spite of a high concentration in the original dust. The PAH composition in benthic organisms (polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high concentrations in the SDS extract of road dust. When testing the toxicity of the extracted contaminants by a standardised algal toxicity test, SDS extracts of a detention pond sediment showed higher toxicity than the pore water of the corresponding sediment. Sediment suspension showed a comparative toxicity with 0.1% SDS extract. From the results, the in vitro bioaccessibility test seems more suitable to evaluate the exposed contaminants than the traditional organic solvent extraction method and the SDS extracted fraction is applicable to toxicity tests reflecting the digestive process.     

北京市北运河流域河水和地下水多环芳烃分布规律及风险评价

为研究北运河流域河水与不同含水层地下水体中多环芳烃(PAHs)的相互作用,收集北运河流域上游温榆河段及下游北运河段不同季节的河水与地下水水质数据,采用对比分析及显著性分析方法研究河水与地下水中多环芳烃的组成、含量及时空分布特征,并利用风险熵法进行风险评价。结果表明:16种优控多环芳烃中,除苯并[a]芘和二苯并[a,h]蒽检出率不足100%外,其余14中多环芳烃污染物在河水、潜水和承压水中均全部检出;多环芳烃总质量浓度的构成以萘为主,质量浓度为1 587.42ng/L,约占总质量浓度的85.6%;潜水和承压水春季多环芳烃总质量浓度显著低于夏季,2～3环多环芳烃质量浓度高于4环以上多环芳烃质量浓度;潜水中多环芳烃总质量浓度高于承压水;北运河段潜水中多环芳烃总质量浓度高于温榆河段;温榆河段地下水主要污染物为萘、芴和菲,北运河段地下水主要污染物为萘、苊和菲;上游河水多环芳烃总质量浓度低于下游,主要污染物为萘和菲;萘、芴、菲、蒽、荧蒽、芘、苯并[a]蒽在不同位置条件下差异显著,除苯并[a]蒽、苯并[b]荧蒽、苯并[a]芘和二苯并[a,h]蒽之外,其余多环芳烃在不同季节条件下均差异显著;通过风险熵法计算得出不同季节和位置条件下研究区生态风险相对较低。     

长江源区近年水质时空分布特征探析

长江源区地处青藏高原,气候条件恶劣,受技术条件限制,有关源区特有的高原生态环境状况的调查和报道较少。根据2012,2014,2015年长江源区科学考察获取的水质监测资料,分析了长江源区常规监测指标、金属类及有机物等水质指标,探析了近几年长江源区水质时空分布特征。结果表明:长江源区河流水质良好,大多数区域的水质指标达到Ⅰ—Ⅱ类水标准;受水体含沙量和区域地质条件的影响,源区不同区域河流水质有一定差异;源区水质年际间差异不大,基本在相同的范围内波动;与国内外河流背景值相比,源区水质基本处于河流背景值范围内;源区有邻苯二甲酸酯类有机污染物检出。该结果对于进一步开展长江源区水生态环境研究具有重要意义。     

Development of extraction procedures for the analysis of polycyclic aromatic hydrocarbons and organochlorine pesticides in municipal sewage sludge.

Land application of sludge as fertilizers is a way of disposal and recycling of sludge. However, public concern has arisen due to the fact that organic contaminants in sludge may ultimately enter the food chain. Hence the need arises to analyse the organic contaminants such as PAHs and OCPs in sludge. In this study, Soxhlet was utilised as the extraction method and the extracts subjected to extensive cleanup via either silica columns or solid phase extraction cartridges prior to analysis using gas chromatography or high performance liquid chromatography. Sludge samples were collected from the drying beds of oxidation ponds in three locations in South Johore. OCPs such as heptachlor, dieldrin and pp-DDT were detected in low amounts (52-159 mg/kg) whereas PAHs such as naphthalene, phenanthrene, fluoranthene and benzo(a)pyrene were detected in the range of 0.2-5.5 mg/kg dry mass. Subcritical water extraction (SWE) recovery studies of PAHs were also performed from spiked sludge samples. Although a recovery range of 41-68% was obtained using the SWE method, the results indicated the usefulness of the technique as an alternative to Soxhlet extraction for the analysis of PAHs in sludge samples.     

松花江区水资源质量评价综述

基于全国第二次水资源调查评价成果,对松花江区地表水资源质量现状进行综合概述。松花江区的地表水体污染严重,以有机污染为主,主要污染指标是CODMn;综合评价水质劣于Ⅲ类的河长占总河长的62.7%;湖泊、水库基本处于中富营养和富营养状态,水质多为Ⅴ类和劣Ⅴ类。汛期污染重于非汛期,面污染源影响大于点污染源;有机污染主要来自农村和田野,城市工业和生活污水也是重要的污染源。     

Micropollutants in stormwater runoff and combined sewer overflow in the Copenhagen area, Denmark

Stormwater runoff contains a broad range of micropollutants. In Europe a number of these substances are regulated through the Water Framework Directive, which establishes Environmental Quality Standards (EQSs) for surface waters. Knowledge about discharge of these substances through stormwater runoff and combined sewer overflows (CSOs) is essential to ensure compliance with the EQSs. Results from a screening campaign including more than 50 substances at four stormwater discharge locations and one CSO in Copenhagen are reported here. Heavy metal concentrations were detected at levels similar to earlier findings, e.g., with copper found at concentrations up to 13 times greater than the Danish standard for surface waters. The concentration of polyaromatic hydrocarbons (PAHs) exceeded the EQSs by factors up to 500 times for stormwater and 2,000 times for the CSO. Glyphosate was found in all samples whilst diuron, isoproturon, terbutylazine and MCPA were found only in some of the samples. Diethylhexylphthalate (DEHP) was also found at all five locations in concentrations exceeding the EQS. The results give a valuable background for designing further monitoring programmes focusing on the chemical status of surface waters in urban areas.     

城市小区雨水径流投加细砂强化混凝沉淀优化条件研究

城市小区雨水径流水质的污染主要为有机污染和悬浮固体污染,且污染物的可生化性差,采用投加混凝剂同时加细砂的强化混凝沉淀实验,确定了小区径流混凝沉淀处理最适宜的混凝剂种类、最佳的混凝反应运行条件及最优的药剂和细砂投加量.实验表明:在混凝沉淀过程中投加细砂,不仅能提高混凝沉淀效果,而且能提高沉淀速度.小区径流强化混凝沉淀的浊度去除率达99.7％,COD去除率达92.6％,处理水的浊度1.66 NTU,COD 35mg/L两主要指标均优于杂用水水质标准.因此,投加细料的混凝沉淀是小区雨水径流处理利用及污染控制最简便易行且有效的处理方法.     

长江干流主要城市江段微量有机物污染分析

It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system.     

PAHs concentration and toxicity in organic solvent extracts of atmospheric particulate matter and sea sediments

The concentration of polycyclic aromatic hydrocarbons (PAHs) and the toxicity to marine bacteria (Vibrio fischeri) were measured for the organic solvent extracts of sea sediments collected from an urban watershed area (Hiroshima Bay) of Japan and compared with the concentrations and toxicity of atmospheric particulate matter (PM). In atmospheric PM, the PAHs concentration was highest in fine particulate matter (FPM) collected during cold seasons. The concentrations of sea sediments were 0.01-0.001 times those of atmospheric PM. 1/EC50 was 1-10 L g(-1) PM for atmospheric PM and 0.1-1 L g(-1) dry solids for sea sediments. These results imply that toxic substances from atmospheric PM are diluted several tens or hundreds of times in sea sediments. The ratio of the 1/EC50 to PAHs concentration ((1/EC50)/16PAHs) was stable for all sea sediments (0.1-1 L μg(-1) 16PAHs) and was the same order of magnitude as that of FPM and coarse particulate matter (CPM). The ratio of sediments collected from the west was more similar to that of CPM while that from the east was more similar to FPM, possibly because of hydraulic differences among water bodies. The PAHs concentration pattern analyses (principal component analysis and isomer ratio analysis) were conducted and the results showed that the PAHs pattern in sea sediments was quite different to that of FPM and CPM. Comparison with previously conducted PAHs analyses suggested that biomass burning residues comprised a major portion of these other sources.