赣江流域底泥中有机氯农药残留特征及空间分布

基于"临水垂直插管法"采集赣江流域32个采样点的底泥样品,经索氏提取方法(Soxhlet Extraction,SE)前处理及气相色谱法(GC-ECD)检测样品中有机氯农药(OCPs)含量。结合多元统计学和ArcGIS9.3,研究了8种有机氯农药的残留状况及空间分布情况。结果表明,所检测8种OCPs中,除β-HCH有2个点未检出,其它7种OCPs检出率为100%。以DDTs残留含量最高,DDTs平均值为10.40μg/kg,其异构体以p,p’-DDT为主;HCHs的平均值为8.24μg/kg,其异构体以β-HCH为主。它们除了来自环境中的早期残留外,仍然具有新的外源HCHs和DDTs的输入。不同OCPs在研究区分布存在很大差异,HCHs总量分布较高的地区位于流域的中下游,DDTs总量分布较高的地区位于流域的中上游。     

宁波滩涂贝类养殖区沉积物中有机氯农药和多氯联苯残留及生态风险评估

利用GC-ECD对宁波市主要滩涂贝类养殖区表层沉积物中的多氯联苯(PCBs)和有机氯农药六六六(HCHs)、滴滴涕(DDTs)的残留量进行测定,研究其分布状况,并进行生态风险评估.结果表明:贝类养殖区表层沉积物中的总有机氯农药含量为0.80～32.40ng·g-1,多氯联苯含量为3.20～33.33 ng·g-1.HCHs主要来自远距离大气传输及历史残留,部分区域有DDTs输入,其来源可能是三氯杀螨醇的使用.大部分站位的p,p’-DDT和DDTs存在潜在的生态风险,其中墙头和西店海域的p,p’-DDT残留超过生物效应中值,对底栖生物毒害效应较高.大多数站位PCBs的生态风险较低.     

太湖区域环境中基于PBPK模型的DDTs和HCHs混合健康风险

针对太湖区域环境中DDTs和HCHs混合暴露的健康危害,基于对居民DDTs及HCHs不同途径暴露量的分析,通过建立DDTs及HCHs的PBPK模型,分析其在人体内的累积分布过程,并应用内效应综合危害指数评价其混合暴露的健康风险。结果表明,居民健康风险度分别为0.147～2.499（男性）和0.138～2.223（女性）,超过可接受风险的概率分别为24.6%（男性）和16.5%（女性）。相较于传统的混合健康风险评价方法（HI法）,基于PBPK模型的内效应综合危害指数法（HI_tissue-dose）更能反映混合健康风险的发展趋势。     

巢湖表层水体中有机氯农药的分布及其组成

以固相萃取-气相色谱法/电子捕获检测器(SPE-GC/ECD)作为检测手段,对巢湖表层水体中有机氯农药(OCPs)的分布及组成特征进行分析.结果表明:研究区13个采样点中共检出包括六六六(HCHs)、滴滴涕(DDTs)、β-硫丹(β-Endosulfan)、艾氏剂(Aldrin)、六氯苯(hexachlorobenzene)和七氯(Heptachlor)在内的16种有机氯农药,其总含量范围为0.54～64.01ng.L-1;16种有机氯农药中以HCHs和DDTs为主,其平均质量浓度分别为5.56ng.L-1和16.57ng.L-1,约占其总量的84.75%;研究区的有机氯农药污染除了主要源于历史上农田中有机氯农药的残留外,近期可能还有新的农药污染源进入水环境;研究区所检出的各类有机氯农药均未超过国家地表水环境质量标准,巢湖表层水体中有机氯农药含量及潜在风险均属于中等偏低水平.     

有机氯农药在大滨鹬和红腹滨鹬体内的富集程度

为探讨东亚-澳大利西亚迁徙路线上的鸻鹬类体内有机氯农药的含量及来源,本研究以该迁徙路线上的大滨鹬(Calidris tenuirostris)和红腹滨鹬(C.canutus)为研究对象,用索氏提取法对这两种鸟的胸肌和皮下脂肪中的有机污染物进行萃取,并用气相色谱法对19种有机氯农药进行检测。结果表明,HCHs、DDTs、硫丹Ⅱ等14种有机氯农药在大滨鹬和红腹滨鹬的组织中均有不同程度的检出,所有样品中的含量最高值达1 573.5 ng/g脂重;在检出的14种有机氯农药中,α-HCH、β-HCH、γ-HCH、p,p′-DDE、硫丹Ⅱ、硫丹硫酸酯和/或p,p′-DDT的检出率达100%;在大滨鹬的肌肉组织、红腹滨鹬的肌肉和脂肪组织中,p,p′-DDE的残留量最高;而在大滨鹬的脂肪组织中硫丹硫酸酯和/或p,p′-DDT的含量最高;目标物中的艾氏剂、异狄氏剂、七氯、反式氯丹等未达检出限或含量较低。我们对比了不同物种及不同组织样本中有机氯农药的富集程度,红腹滨鹬的肌肉组织中HCHs的沉积量显著高于大滨鹬,而大滨鹬的脂肪组织中硫丹硫酸酯和/或p,p′-DDT的含量显著高于红腹滨鹬。此外,分别对比两个物种的肌肉组织和脂肪组织中有机氯农药沉积量,部分有机氯农药在脂肪组织中的沉积量显著高于肌肉组织,说明相比于肌肉组织,有机氯农药可能更易于在脂肪组织中累积。     

管角螺幼体配合饲料中脂肪适宜含量的研究

试验中采用国产鱼粉和进口白鱼粉为蛋白源, 混合油(鱼油︰豆油=1︰1)为脂肪源, 蛋白质含量为40%, 设置了五个脂肪水平: 7%、9%、11%、13%、15%, 选择壳高(2.41±0.04) cm、体重(0.85±0.03) g的管角螺, 以特定生长率和饲料转化率为指标, 研究了上述不同脂肪水平对管角螺的生长和肌肉成分的影响。结果表明, 随着脂肪含量的上升, 特定生长率和饲料转化率均呈现抛物线变化的趋势, 其中脂肪水平为13%组两项指标均最大, 分别达到了0.61%和37.81%, 15%组最小, 分别为0.37%和27.31%, 将特定生长率和饲料转化率分别与饲料脂肪水平进行拟合, 得出管角螺配合饲料最适脂肪含量为12.86%-13.33%。试验结束后对管角螺肌肉主要营养成分进行测定发现, 随饲料脂肪含量的增加, 管角螺肌肉粗蛋白和水分含量均降低, 粗脂肪含量升高, 粗灰分无显著性变化(p>0.05); 肌肉脂肪酸含量不同, 其中13%组的单不饱和脂肪酸最多, 为19.90%, 7%组的多不饱和脂肪酸最多为44.24%。     

重金属在珠江口海域两种腹足类动物组织中的分布与累积

通过测定珠江口海域典型腹足类动物习见蛙螺(Bursa rana)和棒锥螺(Turritellabacillum)各组织器官中重金属(Cu、Zn、Pb、Cd和As)的含量,研究了腹足类动物重金属的组织分布及累积模式.结果表明:肠与肝脏重金属累积模式差异较大,腮在两种螺累积重金属的过程中可能扮演着重要角色,性腺是重金属在螺体的重要累积器官;人体通过食用习见蛙螺和棒锥螺肌肉摄入的重金属虽未超过国际食品法典委员会提出的最大容许摄入量,但重金属联合毒性的潜在危害值得引起高度关注.     

福建漳江口水环境中滴滴涕（DDTs）的分布与溯源

采用气相色谱(GC-ECD)方法分析了漳江口水环境中表层水、沉积物和水生生物体内滴滴涕(DDTs)的污染水平,初步研究了其在多介质中的含量、转移分配规律,并根据其沿江分布规律、组成特征,结合三氯杀螨醇同步调查结果进行了溯源分析.结果表明: 漳江口表层水中的DDTs平均含量为枯水期10.5 ng·L^-1(未检出～20.1 ng·L^-1)、丰水期28.3 ng·L^-1 (未检出～45.2 ng·L^-1)、平水期5.03 ng·L^-1 (未检出～18.8 ng·L^-1);表层沉积物中DDTs含量(以干质量计)为1.87～144 ng·g^-1,平均17.3 ng·g^-1;11种水生生物中DDTs的含量范围为1.09～432 ng·g^-1,平均37.0 ng·g^-1.与其他地区相比,漳江口表层水和沉积物中的DDTs残留属于中等水平.DDT在沉积物中的富集因子为1185;在生物体中的富集因子平均为2534,富集能力依次为水生植物<虾类<贝类<鱼类.DDTs沿江分布基本呈下降趋势,推断其残留与船舶防污剂释放关系不大,主要来源于陆源性污染.组成特征分析显示,漳江口DDTs主要来源于环境中的早期残留,而Y-8站(江心岛后)近期有新的DDTs输入,可能与三氯杀螨醇的使用有关.同步调查结果显示,Y-8站表层水和沉积物中均检出三氯杀螨醇,且含量最高,近期存在三氯杀螨醇的施用.     

管角螺幼螺配合饲料中蛋白质适宜含量的研究

采用国产鱼粉+进口白鱼粉为蛋白源,混合油(鱼油∶豆油=1∶1)为脂肪源,设置了5个蛋白水平:25%、30%、35%、40%、45%(脂肪含量为9%)以特定生长率、饲料转化率和蛋白质效率为指标,在水温(29.7±1.9)℃,盐度24.5±2.5下,研究了上述不同蛋白质水平对管角螺的生长和肌肉成分的影响。选择壳高(2.25±0.25)cm、体重(0.65±0.25)g的管角螺,结果表明,随着蛋白质含量的上升,特定生长率、饲料转化率和蛋白质效率均呈抛物线变化趋势,分别在蛋白质水平为40%、40%和35%时取得最大值1.02%、60.1%和1.62%,且各组间差异性显著(P<0.05)。将特定生长率和饲料转化率分别与饲料蛋白质水平进行拟合,得出饲料蛋白质的最适含量分别为37.50%和38.88%。试验结束后对管角螺肌肉主要营养成分进行测定,发现随饲料蛋白质水平的增加,肌肉中粗蛋白和水分含量均增大,粗脂肪含量减小,且各组间差异性显著(P<0.05),粗灰分无显著性变化(P>0.05)。对肌肉氨基酸进行分析得出,饲料蛋白质水平不同,管角螺肌肉中的氨基酸含量也不同,蛋白质水平为45%组的氨基酸总量、必需氨基酸和鲜味氨基酸含量最多,25%组的最少,后者比前者分别少74.27%、17.47%和44.48%。EAA/TAA和EAA/NEAA略小于FAO/WHO,苯丙氨酸+酪氨酸是第一限制性氨基酸,蛋氨酸+胱氨酸为第二限制性氨基酸。     

Organochlorine Pesticides in Sediments around Chaohu Lake: Concentration Levels and Vertical Distribution

Eighteen organochlorine pesticides (OCPs) were investigated in surface sediments from the Nanfei River and in four sediment cores from the primary estuaries of Chaohu Lake, Eastern China. The results indicate that the OCP concentrations in the surface and core sediments around Chaohu Lake were 3.48–121.08 (with a mean of 34.93) ng/g and 0.60–39.28 (7.07) ng/g, respectively. Significantly higher concentrations of ΣOCPs were observed in sediment samples from the Nanfei River and its estuary. The three important OCP contributors around Chaohu Lake were dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), and hexachlorobenzene (HCB), which originated primarily from the historical use of technical DDTs and HCHs. A principal component analysis (PCA) suggests that HCB and lindane may originate from the same sources, and DDTs were greatly influenced by organic carbon from the soil environment and the impact of urbanization processes.     

Levels of Hexachlorocyclohexanes and Dichloro-Dipheny-Trichloroethanes in Penguin Droppings Collected from Ardley Island,Maritime Antarctic

This article reports the concentrations of hexachlorocyclohexanes (HCHs) and dichloro-diphenyl-trichloroethanes (DDTs) in fresh Gentoo penguin (Pygoscelis Papua) droppings deposited on the Ardley Island (62°13′S, 58°56′W), West Antarctica, and those in the island's two lake cores. In the fresh penguin droppings, metabolites were the predominant constituents of the DDT group, most likely due to the ban on DDT use in agriculture and the higher stability of the metabolites in the environment. In contrast, γ-HCH comprised 66% of the total HCHs, apparently due to the continuous use of Lindane in the Southern Hemisphere. The concentrations of HCHs and DDTs in the fresh droppings are many times higher than those in penguin plume, the latter currently being used as biomaterial for monitoring coastal contaminations in Antarctica. Results of this study indicate that penguin droppings have a good potential for use as another biomonitoring material in detecting the organochlorine pesticides and other contaminants in the maritime Antarctic. Because penguin droppings can be well preserved in lake sediments, they also provide a good and continuous historical record of these contaminants. The slight increase of DDTs since the 1990s, as observed in the aged penguin droppings in the sediment cores, suggests there have been new inputs of DDT into the Antarctic coastal ecosystem, probably from the illegal use of DDT in the Southern Hemisphere.     

Characterization,ecological and health risks of DDTs and HCHs in water from a large shallow Chinese lake

The levels of dichloro diphenyl trichloroethanes (DDTs) and hexachlorocyolohexanes (HCHs) in water from Lake Chaohu were measured. The residues, possible sources and potential ecological and health risks of these compounds were analyzed. The results show that the contents of total DDTs and HCHs in the water varied from 1.52 to 21.79 and from 1.58 to 31.66 ng L^− 1, respectively, which were higher than those in other Chinese lakes. The main sources of HCHs and DDTs were lindane and technical DDT, respectively. The o,p′-DDT/p,p′-DDT ratios indicated the new illegal inputs of DDT in all studied inflow rivers and some lake areas. The MOS10 (margin of safety) values suggested that the Lake was facing a potential ecological risks from p,p′-DDT, whereas the risk of γ-HCH was small. Both carcinogenic and noncarcinogenic risks of DDTs and HCHs associated with the water use were very low.     

Occurrence,distribution and possible sources of organochlorine pesticides in peri-urban vegetable soils of Changchun,Northeast China

The characterizations of residue levels and sources of organochlorine pesticides (OCPs) in soils are necessary to evaluate the potential pollution and risks of OCPs to the ecosystems and human health. A total of 51 surface soil samples were collected from peri-urban vegetable fields of Changchun and 13 OCPs were analyzed to learn the composition, spatial distribution and sources. The concentrations were in the ranges of 0.94–107.8 ng g^?1 for DDTs, 0.89–98.3 ng g^?1 for HCHs, 0.22–18.20 ng g^?1 for Chlordanes, nd–4.49 ng g^?1 for aldrin and nd–9.66 ng g^?1 for dieldrin, respectively. The total OCPs concentrations ranged from 2.44 to 177.1 ng g^?1 and the higher residues were mainly distributed in northeast and southwest sites, as well as sites along the Yitong River. According to the concentrations and detection frequencies, DDTs and HCHs were the most dominant compounds. Compositional analysis and principal component analysis suggested that DDT, HCH and chlordane in most soil samples derived from historical application except the slight fresh introduction at some locations. There exist a variety of OCPs residues in peri-urban vegetable soils of Changchun, but it is still safe and suitable for agricultural production for the most part, and some specific locations with high OCPs residues ought to be a cause for concern.     

Pollution assessment of organochlorine pesticides in urban agricultural soils of Jilin City,China

The content, source, and pollution level of organochlorine pesticides (OCPs) in soils are necessary to assess potential risks to eco-environment and human health, and to target environment-friendly policies. A total of 50 surface soil samples were collected from urban vegetable fields of Jilin City and thirteen OCPs were analyzed. The concentrations were in the ranges of 3.16–48.35 ng·g^?1 for Dichloro-Diphenyl-Tricgloroethanes (DDTs, sum of o, p′-DDT, p, p′-DDT, p, p′-DDD, and p, p′-DDE), 4.37–44.77 ng·g^?1 for Hexachlorocyclohexanes (HCHs, sum of α-HCH, β-HCH, γ-HCH, and δ-HCH), 1.19–13.17 ng·g^?1 for Chlordanes (sum of heptachlor, t-chlordane, and c-chlordane), 0.24–2.60 ng·g^?1 for aldrin, and nd–3.43 ng·g^?1 for dieldrin, respectively. The different compositions indicated that the residues of DDTs and HCHs originated mainly from the historical application, while chlordanes were mostly from recent input. On the basis of soil quality standards of China and the Netherlands, DDTs and chlordanes in this study were categorized as light pollution, and HCHs were classified as no pollution for the majority of soil samples. There are a variety of OCPs residues in urban vegetable soils of Jilin City, but it is still safe and suitable for agricultural production.     

Input of organochlorine compounds by snow to European high mountain lakes

1.  Persistent organic pollutants (POPs) can be trapped by and accumulate in cold regions. To understand POP accumulation in temperate high mountain lakes, we collected samples of snow from the catchments of several high mountain lakes in Europe.
2.  Organochlorine compounds (OCs) are regularly found in snow collected in European high mountain sites. Polychlorobiphenyls (PCBs) were found in all samples examined. Hexachlorocyclohexanes (HCHs) are also common whereas DDTs and hexachlorobenzene were found less frequently.
3.  Comparison of the concentrations of these pollutants in snow with OC levels in the waters of these lakes or atmospheric deposition during cold periods shows that the snowpack constitutes a significant seasonal PCB reservoir in all catchments and that snow trapping is a major mechanism for the incorporation of HCHs in the lakes situated in the coldest sites, e.g. Gossenköllesee in the Alps.
4.  Correlation of the concentrations of the PCB congeners in snow versus mean annual winter temperature shows higher accumulation at lower temperatures. The less volatile PCBs exhibit higher temperature dependences than the more volatile congeners. This trend differs from altitudinal dependences observed in other sites such as Canada and may be related to the specific range of winter temperature in each area of study.     

Persistent organic pollutants in the blood of free-ranging sea otters (Enhydra lutris ssp.) in Alaska and California

As part of tagging and ecologic research efforts in 1997 and 1998, apparently healthy sea otters of four age-sex classes in six locations in Alaska and three in California were sampled for persistent organic pollutants (POPs) and other chemicals of ecologic or environmental concern (COECs). Published techniques for the detection of POPs (specifically ∑polychlorinated biphenyls [PCBs], ∑DDTs, ∑hexachlorocyclohexanes [HCHs], ∑polycyclic aromatic hydrocarbons [PAHs], ∑chlordanes [CHLs], hexachlorobenzene [HCB], dieldrin, and mirex) in the tissue of dead otters were modified for use with serum from live sea otters. Toxic equivalencies (TEQs) were calculated for POPs with proven bioactivity. Strong location effects were seen for most POPs and COECs; sea otters in California generally showed higher mean concentrations than those in Alaska. Differences in contaminant concentrations were detected among age and sex classes, with high levels frequently observed in subadults. Very high levels of ∑DDT were detected in male sea otters in Elkhorn Slough, California, where strong freshwater outflow from agricultural areas occurs seasonally. All contaminants except mirex differed among Alaskan locations; only ∑DDT, HCB, and chlorpyrifos differed within California. High levels of ∑PCB (particularly larger, more persistent congeners) were detected at two locations in Alaska where associations between elevated PCBs and military activity have been established, while higher PCB levels were found at all three locations in California where no point source of PCBs has been identified. Although POP and COEC concentrations in blood may be less likely to reflect total body burden, concentrations in blood of healthy animals may be more biologically relevant and less influenced by state of nutrition or perimortem factors than other tissues routinely sampled.