典型石油炼制厂地下水中优先控制污染物识别方法的建立和验证

为识别反映地下水质量的优先控制污染物,基于污染物危害性评价体系,结合某炼厂污染物的检出率、检出浓度和超标倍数,建立了石油炼化企业地下水中优先控制污染物识别方法;采用该方法对石油炼制厂地下水污染物进行了筛选研究。结果表明,石油炼化行业地下水中优先控制污染物清单包括苯、甲苯、乙苯、二甲苯、石油烃、苯酚、挥发性酚类、砷、铅和锰等10种5类污染物。研究结果与实验监测结果具有一致性,石油炼化厂地下水污染应优先控制清单中污染物,尤其是苯系物和石油烃。     

运用改进综合评分法筛选典型污染物的研究——以大武水源地地下水典型污染物筛选为例

结合潜在危害指数法和综合评分法筛选大武水源地地下水典型污染物。鉴于潜在危害指数法不考虑污染物的环境浓度,将潜在危害指数作为综合评分法的评价指标之一,同时引进污染物的检出频率、生物降解性、生物累积性、研究区是否有污染源检出、是否为环境激素、是否为美国环境保护署(EPA)优先有机污染物、是否为中国优先污染物、是否为持久性有机污染物等指标,计算不同污染物的综合得分,再通过聚类分析,筛选出典型污染物。研究结果表明,大武水源地地下水典型污染物为三氯甲烷、三氯乙烯、四氯乙烯、四氯化碳和苯。     

基于层次分析法-熵权法的污染地块异味污染物优先度评价方法——以农药类污染地块为例

土壤中异味污染物的风险管控已成为我国农药化工等行业污染地块环境管理的迫切需求。为筛查土壤优先控制异味污染物,研究基于土壤中挥发性异味污染物的迁移、暴露过程和危害效应的系统量化与分析,建立了污染地块异味污染物优先度评价指标体系;采用层次分析法-熵权法确定指标综合评价权重,分析了异味污染物优先度的影响因素,并选取3个农药类案例地块进行验证性评价。结果表明,构成地块异味污染物优先度排序指标体系第二层次的4个准则中,影响程度从高到低为：危害性、迁移性、防护性与暴露性;第三层次15个要素主客观综合权重范围为0.033 6~0.149 6,其中嗅阈值权重最高。案例地块异味污染物基于层次分析法-熵权法的优先度评价等级与基于实测数据通过异味活度值和健康风险影响评价的等级具有一致性。本研究结果可为异味污染地块优先控制异味污染物的筛查提供参考。     

地下水中潜在危害有机物识别与筛选方法

针对地下水中频繁检出的各类有机物,运用理论方法定量计算污染物对地下水的危害系数,对有机物的污染调查、地下水污染防治具有一定的指导意义。为研究有机物对地下水的危害性,汇总了535项有机物,目前这些指标在国内外水质标准中均没给出标准值。从有机物的自身属性入手,假定所有物质处于相同的外界环境中,经过包气带吸附、降解、挥发等作用,分析其进入地下水的难易程度。利用美国环保局的软件EPI Suit4.10,获取了指标的有机碳吸附系数(Koc)、半衰期(DT50)和亨利常数(KH),并结合毒性参数基于健康的评价基准值,构建了污染物潜在危害参数体系。运用3种方法计算有机物的危害系数H、污染指数G和衰减系数K,对比3种计算结果,筛选出100项潜在危害有机物。分析表明,所筛选出的100项指标毒性较大、难挥发,并且有机物的Koc对污染指数(G)和衰减系数(K)的贡献比DT50、KH更大。     

Residues of persistent organic pollutants in frequently-consumed vegetables and assessment of human health risk based on consumption of vegetables in Huizhou,South China

Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), 16 phthalate esters (PAEs), eight organochlorine pesticides (OCPs) and seven polychlorinated biphenyls (PCBs) in 17 frequently-consumed varieties of vegetables collected from 48 sites in Huizhou were measured. Concentrations of PAHs and PAEs of leafy vegetables were higher than those of gourd and fruit vegetables but it was the opposite for OCPs and PCBs. A questionnaire of 450 local residents on vegetable consumption showed that the total vegetable ingested rates of females and males were 278.80 g person⁻¹ d⁻¹ and 282.92 g person⁻¹ d⁻¹, respectively. The weight-specific daily intakes of pollutants by females were higher than those by males because of differences in body weight. Twenty-seven pollutants were used to assess the potential risk to human health by calculating target hazard quotient (THQ) values. Results showed that the risk to females was higher than for males. OCPs were the major contributors to the risk for both females and males. The main risks were from consumption of eggplant, Chinese lettuce and luffa and were significantly related to the contents of di-nonyl phthalate, β-hexachlorocyclohexane, γ-hexachlorocyclohexane, p,p-dichlorodiphenyltrichloroethane and p,p-dichlorodiphenyl dichloroethane in vegetables. Although the THQ values induced by individual pollutants were relatively low, the total THQ values induced by 27 pollutants were above 1 in some administrative regions of Huizhou, which might give cause for concern.     

The identification of readily bioavailable pollutants in lake shkodra/skadar using semipermeable membrane devices (SPMDs), bioassays and chemical analysis

GOAL, SCOPE AND BACKGROUND: Lake Shkodra/Skadar is the largest lake in the Balkans region and located on the border between Albania to the south and Montenegro to the north. Because of the wide range of endemic, rare or endangered plant and animal species it supports, Lake Shkodra/Skadar and its extensive associated wetlands are internationally recognised as a site of significance and importance (Ramsar site). In recent years, social and economic changes in both Albania and Montenegro have lead to unprecedented levels of urban and industrial effluent entering the lake. Of particular concern is the increasing input of toxic hydrophobic organic pollutants (HOPs) into the lake and the degree to which these compounds are available for uptake by aquatic biota. Semipermeable membrane devices (SPMDs) have been shown to sample the readily bioavailable fraction (dissolved phase) of waterborne HOPs and in doing so provide relevant data for exposure assessment. The aim of the current study was to use SPMD-based sampling in conjunction with appropriate bioassays and chemical analysis to identify readily bioavailable HOPs in the lake. METHODS: SPMDs were constructed and deployed at three sites in the Albanian sector and three sites in the Montenegrin sector of Lake Skadar/Shkodra for 21 days. Following the dialytic recovery of target analytes and size exclusion chromatographic clean-up, aliquots of SPMD samples were subjected to GC-MS scan analysis for major components, GC-MS SIM analysis for 16 priority pollutant polycyclic aromatic hydrocarbons (PP-PAHs) and assayed for EROD-inducing, estrogenic and mutagenic potential using rainbow trout liver cells (RTL-W1), the yeast estrogen screen (YES) and the Ames Test, respectively. RESULTS AND DISCUSSION: A total of 39 compounds were tentatively identified in SPMD samples from the six sampling sites. Alkylated PAHs were the most abundant and ubiquitous compounds present along with various sterols and sterol derivatives. Numerous other compounds remain unidentified. 15 of the 16 targeted PP-PAHs were present in samples from one or more of the sampling sites indicating these compounds are both readily bioavailable and widely distributed in Lake Shkodra/Skadar. Total PP-PAH concentrations ranged between 3991 ng/SPMD and 10695 ng/SPMD. Bioassays carried out on SPMD samples revealed significant EROD-inducing and estrogenic potential at five of the six sampling sites indicating toxicologically relevant compounds are readily available for uptake by resident aquatic biota. EROD-inducing potential was positively correlated with targeted PP-PAH concentration (r2 = 0.74). However, comparison of bioassay- and analytically-derived toxicity equivalents revealed targeted PP-PAHs were responsible for less than 0.06% of the total EROD-inducing potential. CONCLUSIONS AND OUTLOOK: The combination of SPMD-based sampling with appropriate bioassays and chemical analysis provided an effective tool for the identification of environmentally relevant waterborne pollutants in Lake Shkodra/Skadar. Our results show that toxicologically relevant HOPs including EROD-inducing and potentially estrogenic compounds are widely distributed in the lake and readily available for uptake by aquatic biota. Our results also suggest that alkylated PAHs rather than parent compounds may be of greater toxicological relevance in the lake. As anthropogenic influences continue to increase, SPMD-based sampling is expected to play a central role in future research concerned with the identification, monitoring and assessment of the risk posed by HOPs to Lake Shkodra/Skadar's aquatic biota.     

Regional dynamics of persistent organic pollutants (POPs) in the Pearl River Delta, China: implications and perspectives

The mass transport budgets of 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (p,p′-DDT) and decabromodiphenyl ether (BDE-209) in the Pearl River Delta, South China were calculated based on previously collected data. Residual p,p′-DDT, mostly related to historical use, has largely settled into soil (780,000 kg), while the soil BDE-209 inventory (44,000 kg) is considerably smaller. Conversely, large amounts of BDE-209 currently used in numerous commercial products have resulted in a much higher atmospheric depositional flux of BDE-209 (28,100 kg/yr) relative to p,p′-DDT (310 kg/yr). The soil inventory of p,p′-DDT is predicted to decrease to half of its current value after 22 years, and the percent area containing soil p,p′-DDT at levels exceeding the effects range-medium (27 ng/g) will decrease from 40% to 20%. Finally, soil BDE-209 inventory will reach an equilibrium value of 940 tons in ∼60 years, when BDE-209 levels in 50% of soil will be above an equivalent risk guideline value (125 ng/g).     

Distribution and ecotoxicological concerns of persistent organic pollutants in sediment from creek ecosystem

In order to study the distribution and ecotoxicological concerns of persistent organic pollutants, grab sediment samples were collected from different locations across Thane creek, India. Analyses of samples were carried out using gas chromatography (GC)–electron capture detector and GC–mass spectrometry techniques. In organochlorine pesticides (OCPs), DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl) ethane), DDE (1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene), DDD (1-chloro-4-(2,2-dichloro-1-(4-chlorophenyl)ethyl) benzene) and α, β, and γ conformer of hexachlorocyclohexane (HCH), and 9 polychlorinated biphenyls (PCBs) congeners were analyzed in surface sediment samples. Concentrations of these pollutants in grab sediment samples may indicate their current use and impact on marine ecosystem. Average concentrations of total DDT (including DDD and DDE), HCH, and Σ₉PCBs were found to be 4.9, 12.5, and 2.9 µg kg^?1(dry weight) respectively. High concentrations of OCPs and PCBs were found at discharge locations in creek compared to other locations. Location-wise distribution of OCPs and PCBs indicates their high concentrations at the waste water receiving point. Data were compared for ecotoxicological impacts based on the levels specified in the sediment quality standards of the US Environmental Protection Agency and the Canadian Council of Ministers of the Environment. γ-HCH was found to have maximum potential to induce ecotoxicological impacts.     

我国持久性有机污染物状况及宏观对策

从近几十年来中国POPs的使用情况出发 ,系统分析了典型POPs物质在农产品、土壤、母乳、水体和沉积物等介质中的污染状况。分析了国际上控制POPs的动向以及中国采取的应对策略 ,并对中国控制POPs污染的宏观对策进行探讨。从总体上看 ,目前中国有关POPs的政策法规体系正逐渐与国际接轨 ,但还很不完善 ,缺乏针对性和对污染事故的责任、处罚等明确措施 ,控制POPs对环境的污染与危害 ,制定行之有效的环境监管措施势在必行。     

Effects of hydrodynamics on the distribution of trace persistent organic pollutants and macrobenthic communities in Bohai Bay

In recent years, the rapid economic development along Bohai Bay, has brought out continuous increasing of the pollution loads in the Bohai Sea, especially by the large coastal reclamation project, Tianjin Binhai New Area. In the period of 2007-2009, we collected the sediments of the main rivers, estuaries, intertidal zone, and near-shore area of Bohai Bay, and Macrobenthos associated with the marine sediments to assess the influence of hydrodynamics in the coastal environment on the pattern of trace contaminants and the macrobenthic community. Based on data derived from these samples, the levels of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in sediments followed the order PAHs > OCPs > PCBs > PBDEs. The higher concentrations of PCBs, OCPs, PAHs and PBDEs were found in the estuarine and near-shore environment of the Dagu Drainage River. The spatial distribution of OCPs was different to that of PCBs due to the direction of the velocity field of Bohai Bay in its old and new topography, and the higher water-solubility of OCPs than that of PCBs. The results of the Pearson correlation and the PCA indicate that the medium diameter (MD) of sediments was the predominant factor influencing the distribution of PCBs and OCPs, most sampling sites were characterized mainly by TOC of sediments and biomass of macrobenthos. The results indicate that the distribution of trace contaminants and macrobenthic community in Bohai Bay are mainly affected by the hydrodynamic conditions.     

Pilot survey of a broad range of priority pollutants in sediment and fish from the Ebro river basin (NE Spain)

Priority organic pollutants were investigated in sediments and fish collected along the Ebro river basin (NE Spain) to evaluate their occurrence, transport and bioavailability. Sediments were collected in 18 sites and two species of fish were captured in nine sites according to the availability in each area. The sampling sites covered industrial, urban and agricultural areas. Four methods were used to detect 20 organochlorine compounds (OCs), 8 polycyclic aromatic hydrocarbons, 3 organotin compounds, 2 alkylphenols and 40 polybrominated diphenyl ethers (PBDEs) from purified extracts. The contamination pattern was site specific and no downstream increase in concentration of pollutants was observed but rather a generalized low level diffuse pollution. Target compounds were detected in sediments at 0.01 to 2331 microg/kg dry weight, and only OCs and PBDEs were accumulated in benthopelagic fish. Toxicological assessment was performed according to predicted environmental levels and revealed sites where adverse effects could occur.     

折流式水解反应器处理印染废水水温影响研究

在水温为5℃、9.7℃、14.9℃、19.7℃、23.5℃和31.1℃6种温度的条件下,应用折流式水解反应器对印染废水进行水解试验研究.结果表明,提高水温可增大COD、色度及UVA254的去除效率,相应的ORP值变小,pH值升高,水解程度加深.水温5℃时,水解效果较差;水温在10～23.5℃内,水解效果相对较好,31.1℃水解效果最好,研究结果能为工程应用提供一定的参考.