长江南京段水、悬浮物及沉积物中多氯有毒有机污染物

对长江南京段水、悬浮物及沉积物中多氯有毒有机污染物进行了分析测定,由色谱/质谱测得的结果表明,水和沉积物中多氯有机污染物的浓度较低,低于欧洲主要河流中的含量水平.悬浮物中这类污染物总含量较高,为56.45～62.35μg/kg,而水中总含量仅为14.61～15.83ng/L.由于长江中污染物被充分稀释与混匀,各采样点的水和悬浮物中该类污染物的浓度变化不大,两相间具有较好的相关性.但各采样点的沉积物中多氯有机污染物含量差异甚大,表明悬浮物的沉积极不均一.沉积物中主要污染物是六氯苯（HCB）和它的代谢产物五氯苯（PeCB）以及滴滴涕（DDT）的代谢产物,其他多氯有机污染物含量很低.     

城市污水污泥中PCBs的分析及其QA/QC研究

采用正己烷/丙酮混合萃取剂索氏提取污泥,浓硫酸洗涤和硅胶层析柱净化分离出纯净的PCBs,以毛细管GC-ECD和内标法对PCBs定量,并进行了QA/QC研究.以实际城市污水污泥作为加标基质,方法的检测限为0·92—2·82ng·g-1(干重),19种PCBs同族体的回收率为54·2—140·6%,相对标准偏差为6·5—15·3%,满足US EPA对PCBs回收率的要求.经过3次平行分析,城市污水污泥中含有12种PCBs,PCBs总量的平均值为115·73ng·g-1(干重),相对标准偏差为9·57%.     

Monitoring of air pollution by polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans of pine needles in Korea

The atmospheric contamination levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were evaluated from the analysis of pine needles in South Korea. Pine needles were collected from 30 sampling points at five main cities in South Korea (Busan, Daegu, Gwangju, Changwon and Jeju island). The highest concentrations of PCDDs/DFs (2.19–26.88 pg I-TEQ/g of dry weight) were measured at Busan, where is the city of the highest population density and traffic volume among five cities. The lowest concentration was detected at Jeju with 0.62 pg I-TEQ/g dry weight, suggesting Jeju could be an environmental background area in Korea. The dominant homologues of PCDDs/DFs in pine needles were the lower chlorine-substituted compounds such as tetra CDDs and CDFs, and the distribution ratios of PCDDs/DFs decreased with increase of the number of chlorine substituents. Homologue profiles of pine needle samples were similar to PCDDs/DFs profiles of the vapor phase in the ambient air, and thus the pine needles absorbed the vapor phase of PCDDs/DFs from air. Results suggested that pine needles could be used as an indicator of the atmospheric contamination for PCDDs/DFs in Korea.     

Development of GC capillary column for isomer-specific separation of toxic isomer of PCDDs and PCDFs in environmental samples

Analysis of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) has been performed using gas chromatography mass spectrometry (GC-MS). Analysis of the most toxic isomers, in particular, 2,3,7,8-substituted PCDD/PCDF in the presence of other isomers requires a special isomer specific capillary column or high performance liquid chromatography (HPLC) fractionation prior to GC-MS analysis. Commercially available long (>50 m) polar columns can separate 2,3,7,8-TCDD from other tetra isomers. However, those columns are not satisfactory for the analyses of total PCDD/PCDF in the environmental samples. Gas chromatography -high resolution mass spectrometry (GC-HRMS) and GC-MS/MS techniques are not helpful in the analysis of 2,3,7,8-TCDD unless it is separated from the other tetra isomers. The analysis of 2,3,7,8-TCDD and total PCDD and PCDF in a single GC-MS run can ease the laborious techniques presently used. In this study we have developed a new stationary phase for the GC capillary column. The capillary column developed using this new stationary phase showed unsurpassed selectivity for the separation of 2,3,7,8-TCDD from other tetra isomers. There are several advantages of the newly developed GC capillary column.     

Results from the first year of the Swedish dioxin survey

PCDD/F levels are presented for food baskets, raw and fried herring, wolf muscle and moose tallow collected from the same area, three burbot liver samples, a sediment core from the Baltic Sea and leach water from three garbage dumps. Levels in food baskets were at or below detection limits making the estimation of intake via the diet difficult. Frying herring produces no net change in PCDD/F levels. Moose have lower PCDD/F levels than wolf from the same area. Levels in burbot liver samples are much higher near industrial discharges than in a more undisturbed area. The top 4 cm of the sediment core contain the highest levels of PCDD/F. Thereafter the levels drop and reach a low level. This low level is probably caused by contamination during sampling and is not evidence of PCDD/F presence far back in time. Leach water from city dumps contains low levels of PCDD/F but that from a dump that takes industrial wastes had higher levels and a different congener pattern.     

Analysis of Ah receptor pathway activation by brominated flame retardants

Brominated flame-retardants (BFRs) are used as additives in plastics to decrease the rate of combustion of these materials, leading to greater consumer safety. As the use of plastics has increased, the production and use of flame-retardants has also grown. Many BFRs are persistent and have been detected in environmental samples, raising concerns about the biological/toxicological risk associated with their use. Most BFRs appear to be non-toxic, however there is still some concern that these compounds, or possible contaminants in BFRs mixtures could interact with cellular receptors. In this study we have examined the interaction of decabromodiphenyl ether, Firemaster BP4A (tetrabromobisphenol A), Firemaster PHT4 (tetrabromophthalic anhydride), hexabromobenzene, pentabromotoluene, decabromobiphenyl, Firemaster BP-6 (2,2^′,4,4^′,5,5^′-hexabromobiphenyl) and possible contaminants of BFR mixtures with the Ah receptor. Receptor binding and activation was examined using the Gel Retardation Assay and increased expression of dioxin responsive genes was detected using the reporter gene based CALUX assay. The results demonstrate the ability of BFRs to activate the AhR signal transduction pathway at moderate to high concentrations as assessed using both assays. AhR-dependent activation by BFRs may be due in part to contaminants present in commercial/technical mixtures. This was suggested by our comparative analysis of Firemaster BP-6 versus its primary component 2,2^′,4,4^′,5,5^′-hexabromobiphenyl. Some technical mixtures of brominated flame-retardants contain brominated biphenyls, dioxins or dibenzofurans as contaminants. When tested in the CALUX assay these compounds were found to be equivalent to, or more active than their chlorinated analogues. Relative effective potency values were determined from dose response curves for these brominated HAHs.     

Human exposure to dioxins and furans: application of the substance flow analysis to health risk assessment

Substance Flow Analysis (SFA) is an important instrument that allows for the undertaking of environmental management for a specific contaminant. 'Control Analysis' is a tool that assesses the effect on a target flow of changes in flows forming part of a control basis set. The purpose of the present study was to perform a modeling of the annual PCDD/F flows in Tarragona Province and to apply the model for human health risk assessment. The validation of the model has been evaluated by comparing estimated fluxes with experimental values. Eleven subsystems, as well as a set of 88 flows of the system in Tarragona Province were considered. The total PCDD/F accumulation in Tarragona Province was between 62.6 and 159.5 g I-TEQ/y. Accumulation in sediments (27.9-74.6 g I-TEQ/y) and soils (35.0-80.8 g I-TEQ/y) are the two principal modes of deposition. Estimated flow in human adipose tissue means a mean intake of PCDD/F (via ingestion and inhalation) of 243 pg I-TEQ/person/day. The food chain pathway accounts for 99% of the total daily intake. As a result of the simulation, a 100% decrease in industrial emissions would cause a 1.7% reduction in the PCDD/F accumulation in humans. In turn, a 100% reduction of PCDD/Fs in the industrial waste waters would cause only an insignificant 0.1% decrease in the accumulation of PCDD/Fs in humans.     

Flow analysis of PCDD/Fs for Tarragona Province, Spain

The present study was intended to establish an inventory of PCDD/F emissions in Tarragona Province (Catalonia, NE Spain), as a preliminary phase in the development of a flow analysis of PCDD/Fs in this Province. In 1999, global PCDD/F emissions reached a value of 2.24 g I-TEQ/y, which means a density of 3.8 micrograms I-TEQ/inhabitant/y. The low amount of PCDD/Fs emitted to air by the only municipal solid waste incinerator in the Province (approximately 0.04% of the total) has been one of the most notable results. As a reflection of uncertainties in the estimates for individual sources, the 90th percentiles of PCDD/F releases for 1999 ranged up to 4.1 g I-TEQ/y.     

五氯酚及其钠盐中氯代二恶英类分析

采用ＨＰＬＣ和ＧＣ／ＭＳ的方法，对国产ＰＣＰ及其钠盐中的ＰＣＤＤｓ，ＰＣＤＦｓ进行了分析。测定了所有２，３，７，８－取代同系物。此外，还根据各ＣＤＤｓ，ＣＤＦｓ的毒性当量因于ＴＥＦｓ，计算了其毒性当量Ｉ－ＴＥＱｓ，分别为１４２，９２ｎｇ．ｇ＾－１。在前述基础上，仨算了由于ＰＣＰ及其钠盐的应用，引起的ＰＣＤＤｓ，ＰＣＤＦｓ环境输入。约为２４０ｋｇ／ａ。     

手性多氯联苯在电子垃圾拆解地鱼类体内的分布及累积规律

电子垃圾拆解活动已造成当地鱼类多氯联苯（Polychlorinated Biphenyls,简称PCBs）污染,但手性PCBs在鱼类体内的分布特征和选择性富集则较少有报道.本研究采集了广东省清远市龙塘镇某电子垃圾拆解区附近水塘的鱼类样品,研究鱼肉样品中手性PCBs污染水平、分布规律和对映体选择性.结果表明,在电子垃圾拆解区鱼肉样品中均检测到7种手性PCBs,总PCBs（ΣPCBs）含量为386.7~602.8 ng·g^-1（湿重）,证实当地鱼类已受到手性PCBs的污染.PCB45、PCB91、PCB95、PCB132、PCB136和PCB174在鱼类样品的对映体分数（EF值）与沉积物具有显著差异,表明这些手性PCBs在鱼类体内可能具有对映体选择性富集和代谢作用.不同种类的鱼肉样品中EF值不同,说明它们对PCBs的富集能力不同.鲮鱼、鲫鱼和乌鳢对PCBs的生物/沉积物富集因子（BSAF）分别为0.31~1.71、0.30~1.86和0.50~2.64.根据乌鳢/鲮鱼和乌鳢/鲫鱼食物关系计算的生物放大因子（BMF）范围分别为1.35~4.51和2.17~5.10,表明乌鳢对手性PCBs具有生物放大作用.