苏南快速城镇化区域典型河道入河污染物调查分析与估算

针对快速城镇化区域产业快速发展、人口高度密集与排水设施建设滞后间的突出矛盾,以苏州官渎里区域的典型重污染河道——官渎花园内河为研究对象,在分析区域排污特征的基础上,系统总结点污染源、面污染源和内污染源在该类区域的具体表现形式和影响因素,对各类污染物入河量进行调查测算.根据测算结果,官渎花园内河的CODcr、NH3-N、TN和TP年入河量分别为222.54、11.16、16.63和2.56t·a-1.对各污染源贡献率的分析结果表明,工业污染和生活污染为主要污染源,其次为降雨径流污染.在上述测算分析的基础上,结合苏南快速城镇化区域发展特点,提出了若干河道污染控制的对策与建议.     

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.     

In vivo endocrine effects of naphthenic acids in fish

Oil pollution from various sources, including exploration, production and transportation, is a growing global concern. The highest toxicity of hydrocarbon pollutants is associated with the water-soluble phase compounds, including naphthenic acids, a known component found in all hydrocarbon deposits. Recently, naphthenic acids (NAs) have shown estrogenic and anti-androgenic effects in vitro. For this reason we investigated the potential effects of two commercial mixtures of naphthenic acids on fish in vivo, using the three-spined stickleback (Gasterosteus aculeatus) as a model species.     

PAFC对水体中持久性有机污染物PFOA的混凝效果

针对含全氟辛酸(PFOA)的工业废水及应对PFOA的污染突发事件,采用PAFC及其复配粘土矿物凹凸棒和沸石进行混凝实验,并对几个影响因素进行了考察。结果表明,在PAFC的最佳投加量10 mg/L时,PFOA和浊度的去除率分别达到70.25%和99.42%,PAFC混凝处理PFOA的效果优于PAC;pH值对PAFC去除PFOA有一定的影响,当pH大于6时有利于PFOA的去除;PFOA和浊度的去除率随原始浊度的增加而增加;活性炭、盐酸改性凹凸棒、盐酸改性沸石、CT-MAB改性的沸石复配PAFC均可提高PFOA的去除率;改性处理后的沸石应用于PFOA的处理中,有望降低处理成本。     

Factors influencing on the bioaccessibility of polybrominated diphenyl ethers in size-specific dust from air conditioner filters

Size-specific concentrations and bioaccessibility of polybrominated diphenyl ethers (PBDEs) in dust from air conditioner filters were measured, and the factors influencing the PBDE bioaccessibility were determined. Generally, the PBDE concentrations increased with decreasing dust particle size, and BDE209 (deca-BDE) was generally the predominant congener. The bioaccessibility ranged from 20.3% to 50.8% for tri- to hepta-BDEs, and from 5.1% to 13.9% for BDE209 in dust fractions of varied particle size. The bioaccessibility of most PBDE congeners decreased with increasing dust particle size. The way of being of PBDE (adsorbed to dust surface or incorporated into polymers) in dust significantly influenced the bioaccessibility. There was a significant negative correlation between the tri- to hepta-BDE bioaccessibility and organic matter (OM) contents in dust. Furthermore, tri- to hepta-BDE bioaccessibility increased with increasing polarity of OMs, while with decreasing aromaticity of OMs. The tri- to hepta-BDE bioaccessibility significantly positively correlated with the surface areas and pore volumes of dust. Using multiple linear regression analysis, it was found that the OM contents and pore volumes of dust were the most important factors to influence the tri- to hepta-BDE bioaccessibility and they could be used to estimate the bioaccessibility of tri- to hepta-BDEs according to the following equation: bioaccessibility (%) = 45.05 − 0.49 × OM% + 1.79 × pore volume. However, BDE209 bioaccessibility did not correlate to any of these factors.     

Is black carbon a better predictor of polycyclic aromatic hydrocarbon distribution in soils than total organic carbon?

Black carbon (BC) and total organic carbon (TOC) were quantified in the surface soils of Switzerland (N = 105) and Delhi (N = 36), India, to examine their relationships with contents of polycyclic aromatic hydrocarbons (PAH). BC content in Swiss (background) soils (N = 104) varied from 0.41 to 4.75 mg/g (median: 1.13 mg/g) and constituted 1-9% (median: 3%) of TOC. Indian (urban) soils had similar BC concentrations (0.37-2.05 mg/g, median: 1.19 mg/g), with relatively higher BC/TOC (6-23%, median: 13%). Similar to TOC, BC showed significant positive correlation with lighter PAH, but no correlation with heavier PAH in Swiss soils. In contrast, heavier PAH were significantly correlated only with BC in Delhi soils. It seems that TOC governs the distribution of PAH in organic matter rich background soils, while the proximity to emission sources is reflected by BC-PAH association in urban soils.     

Kosetice, Czech Republic--ten years of air pollution monitoring and four years of evaluating the origin of persistent organic pollutants

The regional observatory Kosetice is a central European background station. Unique continuous monitoring from 1988 on is held here. POP (persistent organic pollutant) concentration values of air samples from Kosetice taken between 1996 and 2005 were statistically processed. Values of Czech ambient air quality standards were not exceeded. Concentrations of polycyclic aromatic hydrocarbons reached two maxima, in 1996 and 2001-2002. Polychlorinated biphenyls concentrations reached the highest values in 1997 and 1998 and hexachlorocyclohexanes concentrations in 1998. DDTs, hexachlorobenzene and pentachlorobenzene were analysed as well. Long-range transport of pollutants between 2002 and 2005 was evaluated using the Potential Source Contribution Function hybrid receptor model. Indicated potential source areas of PCBs coincide with many well-known urban and industrialised areas, while the indicated potential source areas of HCHs and DDTs coincide with many agricultural and/or forested regions and the potential source areas of HCB comprise all land use types.     

飞灰螯合剂中挥发性污染物的释放

采集了4个市售飞灰螯合剂样品，分析其在20，40℃下挥发性污染物的释放规律.结果表明，释放的挥发性污染物主要有甲醛、乙醛、苯、异戊醛/异丙醇、甲硫醇、乙硫醇等；其中3个螯合剂样品甲醛的释放浓度在20℃为748~1325 μg/L-螯合剂，占释放的易挥发污染物的68%~96%（质量比），在40℃为4282~6822 μg/L-螯合剂，占释放的易挥发污染物的87%~95%（质量比）.随着温度升高，释放的挥发性污染物种类变多，部分污染物浓度增加，40℃时，4个螯合剂样品释放的易挥发污染物浓度比20℃时增加了142%~444%.元素分析、拉曼光谱和热重分析结果表明，4个螯合剂的主要有效成分相似，为二硫代氨基甲酸盐类物质.因此，推测这种飞灰螯合剂在稀释和飞灰稳定化过程中，对工作人员的健康可能有潜在的危害风险，应收集释放的气体并进行处理；且在飞灰填埋过程中，可能会导致渗滤液中NH₄⁺-N等物质的浓度升高，增加渗滤液的处理难度.     

Filterability of oil sands tailings

In Canadian oil sands mining operations, bitumen is extracted from oil sands using the hot water extraction process, which produces tremendous amounts of tailings. Currently, these tailings are disposed of in large ponds, in which coarse particles settle out relatively quickly and fine particles remain suspended in water and settle very slowly. After years of settling, the fine particles form a stable suspension in water known as mature fine tailings (MFTs). Long-term storage of the MFT is costly and poses a major environmental liability.Oil sands companies are now actively investigating different approaches to replace or reduce the use of oil sands tailings ponds. Filtration of the tailings to produce “dry tailings” for stacking is now being investigated as an alternative by a number of companies. Fast water drainage is a critical step for the filtration process. In this paper, we use simple laboratory-scale filtration tests to evaluate the filterability of the oil sands tailings and to generate a parameter that can be used in filtration scale-up. It was found that the filterability of the original coarse oil sands tailings was relatively low. However, after the fines are flocculated with the coarse particles to form uniform flocs the filterability was improved by several orders of magnitude. The results demonstrate that filtration of the flocculated coarse tailings to produce the “dry” stackable tailings may be viable.