南太湖区域表层沉积物中有机氯化合物及重金属污染现状

对南太湖水域表层沉积物中的19种有机氯化合物及6种重金属的含量、分布及其生态风险进行了研究和评价.所测样品中有机氯农药(OCPs)和多氯联苯(PCBs)含量范围分别为0.51 -4.98、1.49-15.15ng/g(dw),与国内其它水域沉积物中OCPs、PCBs的含量相比处于较低水平.OCPs中的主要污染物是α-六...     

太湖表层沉积物中有机氯农药残留及遗传毒性初步研究

采用GC-ECD对太湖表层沉积物中的有机氯农药含量进行了定性定量分析.太湖20个采样点均有不同程度的有机氯农药检出,16种有机氯农药总量为4.22-460.99ng/g(dw),北部湖区、潮心区以及沿岸区等均有高值点出现,与沉积物有机质含量、氮磷营养盐含量分布并不一致.检出率最高的有机氯农药组分为DDTs、HCHs.DDTs含量检出顺序为P,P'-DDT>P,P'-DDD>P,P'-DDE,说明环境中可能仍然具有DDT箱入特征;HCHs中?HCH,?HCH检出相当,怃-HCH检出较高,主要为早期残留.结合鼠伤寒沙门氏菌/哺乳动物微粒体酶系(Ames)试验研究太湖典型溯区表层沉积物中有机污染物的遗传毒性,初步确定可能的生态风险因子.     

河北西大洋水库沉积物中多环芳烃的分布、来源及生态风险评价

分析了河北西大洋水库沉积物中16种多环芳烃的含量及分布状况,并对其来源和生态风险进行了分析和评估.结果表明,表层沉积物多环芳烃总含量范围在422.36 - 1052.90 ng/g之间,且由库区上游到坝前逐渐升高.水库剖面沉积物中多环芳烃总含量在388.81 - 1205.56 ng,/g之间,自底层20 cm到表层多...     

北京官厅水库-永定河水系水体中持久性有机氯农药污染

报道了官厅水库-永定河水系中持久性有机氯农药的污染水平,研究发现在水体中存在六六六(HCHs), 滴滴涕(DDTs), 七氯等在内的有机氯污染物,在所有13个采样点的水样中,18种有机氯农药的浓度为4.2-96.9 ng/L,其中六六六、滴滴涕的含量分别为0.09-53.5ng/L和nd-46.8 ng/L.对污染来源进行分析,发现除了主要是源于历史上农田中有机氯农药的残留外,近期可能有新的农药污染源进入水环境,如林丹和三氯杀螨醇的使用可能造成了新的有机氯农药污染.和国内主要河流相比,官厅水库-永定河水系中有机氯农药的污染属轻度污染.     

鄱阳湖周溪湾沉积物中有机氯农药和多环芳烃的垂直分布特征

通过分析鄱阳湖周溪湾柱状沉积物中有机氯农药(OCPs)和多环芳烃(PAHs)的垂直分布特征,初步探讨该区OCPs和PAHs的污染历史.结果表明,周溪湾柱状样中OCPs总含量范围在40.4~174.1 ng/g(dw)之间,六六六(HCHs)是其主要影响的化合物(16.5~153.6 ng/g(dw)),其次为氯丹类(Chlordanes)和滴滴涕类(DDTs),含量分别为3.4~44.0和1.0~33.4 ng/g(dw).垂直分布特征显示:沉积相上OCPs的残留量比实际使用情况向后推迟10~20年,1950s 1990s OCPs曾被大量使用,到2000年左右在沉积物残留上达到顶峰,随后残留量逐渐降低;而近20年来,该区已经鲜有新的HCHs、Chlordanes以及DDTs输入.PAHs总含量范围为41.3~384 ng/g(dw),芘和菲的含量最高,分别为17.1~67.1和2.68~139 ng/g(dw).垂直分布特征显示,1972年以前,PAHs总含量变幅不大,然而近10年来PAHs的排放量急剧上升.此外,自20世纪末开始,周溪湾区域PAHs的主要来源由以前的煤燃烧释放转化为交通污染排放,并伴随有石油泄漏情况.     

千岛湖表层沉积物中有机氯农药的残留特征及生态风险评价

对千岛湖表层沉积物中21种有机氯农药(OCPs)的残留现状进行调查,明确HCHs与DDTs的组成特征及源解析,并评估其生态风险.结果表明,千岛湖表层沉积物中共检出12种OCPs,各采样点位OCPs总量的浓度范围在0.43~12.70 ng/g之间,平均值为5.28±4.84 ng/g,处于低残留水平,其中DDTs是主要的残留物,街口、大坝前点位样品出现OCPs高残留.工业DDTs的历史使用是千岛湖表层沉积物DDTs残留的主要来源,仅街口点位样品存在林丹的污染并有新的DDTs输入,应引起重视.利用沉积物质量基准法、沉积物质量标准法分别对千岛湖表层沉积物中OCPs的生态风险进行评价,结果表明部分点位样品中OCPs的残留现状对该区生物可能存在生态风险.     

武汉月湖水体和表层沉积物中25种半挥发性有机污染物分布特性

2006年4月在武汉月湖采集了8个样点的水样和表层沉积物样品,采用气-质联用技术分析了样品中25种半挥发性有机污染物(SVOCs)的含量,探讨月湖受有机物污染的程度.水样中25种半挥发性有机污染物总浓度为564.04-1209.41ng/L,平均值为965.64ng/L.沉积物中总浓度为8500.26-23347.20ng/g(DW),平均值为14832.04ng/g(DW).邻苯二甲酸酯类物质是月湖的主要污染物,其中,邻苯二甲酸乙基己基酯和邻苯二甲酸二丁酯含量最高.多环芳烃、硝基甲苯、异佛尔酮等均有不同程度检出,靠近以前的排污口的样点浓度最高.沉积物中25种半挥发性有机污染物的含量大约是水体中含量的15倍,具有潜在生态风险.     

太湖、洞庭湖野生青虾肌肉中有机氯农药的气相色谱-质谱法测定

使用气相色谱质谱技术测定了青虾肌肉组织中的8种有机氯农药.包括六氯苯、氯丹、滴滴涕(ΣDDTs)、艾氏剂、狄氏剂、异狄氏剂、七氯和灭蚁灵,对太湖和洞庭湖15个点位29组野士青虾样品的测定结果显示,青虾肌肉组织内残留的有机氯农药主要是六氯苯和滴滴涕,六氯苯含量为nd-13.2μg/kg(湿重),滴滴涕含量为0.790-5.82μg/kg(湿重),洞庭湖青虾肌肉中有机氯农药的含量略高于太湖青虾,两湖青虾肌肉残留有机氯农药在枯水期时的含量多数大于丰水期时的含量.     

巢湖表层沉积物中多溴联苯醚的分布和污染源解析

在巢湖不同区域采集了16个表层沉积物样品,利用气相色谱-质谱仪测定沉积物中低溴代多溴联苯醚(LPBDEs)和BDE209的含量,并对其残留、组成、空间分布和污染来源进行分析.结果表明,巢湖沉积物中共计检测到9种多溴联苯醚(PBDEs)化合物.∑LPBDEs的含量为0.001~2.75 ng/g,平均值为1.15 ng/g,平均检测率为44.83%;BDE209的含量为1.16~5.49 ng/g,平均值为2.83 ng/g,检测率为100%.与国内其他区域相比,巢湖沉积物中PBDEs含量总体处于中等水平.巢湖沉积物中各类LPBDEs和BDE209同系物含量为:西半湖东半湖湖心.巢湖沉积物中PBDEs以BDE209为主要成分,不同采样点PBDEs同系物的组成不同.相关性分析表明BDE209与LPBDEs在环境中的迁移存在相关性.     

小白洋淀水-沉积物系统多环芳烃的分布、来源与生态风险

以端村小白洋淀为研究对象,利用GC-MS测定了6个样点水、悬浮物和沉积物中15种优控多环芳烃(PAHs)的含量,分析了其组成与来源特征,探讨了不同多环芳烃单体的生态风险,结果表明:(1)15种优控多环芳烃的总含量(PAH15),水相为40.1-74.0ng/L,算术均值51.0ng/L;悬浮物为2438.0-5927.0ng/g,算术均值4528ng/g;沉积物为466.9-1366.4ng/g,算术均值为755.6ng/g;与国内外有关研究相比,污染较轻,(2)三相中均以2、3环PAHs为主,其比例均高于80%;并且,从水相、悬浮物相到沉积物相,2环PAHs依次降低,3环、4环依次升高,高环检出率和含量也依次升高,(3)沉积物中多环芳烃的来源以生物质燃料(秸秆、薪材)和煤的燃烧为主,以液体化石燃料(汽油、柴油和原油)的燃烧为辅,(4)沉积物中的芴(FLO)、菲(PHE)含量在潜在生态风险效应区间低值(ERL)与中值(ERM)之间,其生态风险几率介于10%-50%之间;其他PAHs单体的含量均低于ERL,其生态风险几率均低于10%.     

Spatial and vertical distribution of organochlorine pesticides in sediments from Daya Bay, South China

The spatial and vertical distribution of organochlorine pesticides (OCPs) has been investigated in Daya Bay, China. The concentration of total OCPs in surface sediment range from 16.66 to 44.04ng/g dry weight with a mean concentration of 26.60ng/g. DDTs and HCHs were the predominant species. The ratios of (DDD+DDE)/DDT reflected a cocktail input pattern of fresh and weathered DDTs. The predominant alpha-HCH and the alpha/beta-HCH ratios indicated that the technical HCH contamination was mainly due to historical usage, although there was fresh input of lindane. The variation profiles of concentrations showed that OCPs were extensively applied between the late 1950s and early 1980s in China. A recent increasing trend in concentrations of DDTs and HCHs was found in both cores. The increasing ratios of (DDE+DDD)/DDT with corresponding decreases of DDE/DDT ratio implied that most of the DDTs deposited after their production ban were more likely "weathered" DDTs derived from soil residues.     

Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides in water columns from the Pearl River and the Macao harbor in the Pearl River Delta in South China

Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) were measured in suspended particles and dissolved phase from the Baiertang water column and the Macao water column samples as collected from the Guangzhou channel of the Pearl River and the Macao harbor, where the sediments were heavily contaminated with organic pollutants. Total OCPs concentration varies from 23.4 to 61.7 ng/l in Baiertang water column and from 25.2 to 67.8 ng/l in Macao column, while total PAHs concentration varies from 987.1 to 2878.5 ng/l in the Baiertang water column and from 944.0 to 6654.6 ng/l in the Macao column. The vertical distribution profiles of pollutants and the partition of pollutants between particles and dissolved phases indicate that the sediments in Baiertang act as an important source of selected pollutants, and the pollutants in water of this region were mainly originated from the release and re-suspension of contaminants residing in the sediments. The sediments in Macao harbor act as a reservoir for organochlorine pesticides, such as DDTs mainly introduced by river inflow from Xijiang and PAHs input by brackish water from the Lingdingyang estuary. Combustion of fossil fuels and petroleum input are the main sources of PAHs in the Macao water column, while combustion of fossil fuels and coal is responsible for the PAHs in the Baiertang water column. The ratios of DDT/(DDD+DDE) for the Macao water column samples demonstrate that such chemicals were input into this region in recent times.     

Assessment of persistent organochlorine pollutants in sediments from Lake Manzala, Egypt

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in surface and core sediment samples collected from Manzala Lake, the largest of the Egyptian coastal lakes. Total concentrations of OCPs and ∑7 PCBs (ICES) in sediments ranged from 0.63 to 31.31 ng/g and 0.26 to 31.27 ng/g, respectively. Geographical distribution indicates that levels of contaminants were significantly higher in areas which are mainly influenced by municipal discharge, indicating significant sources of these compounds in urbanised areas. The composition of DDT and its metabolites suggest old input of DDT. The levels of contaminants in Manzala Lake were similar or lower than those observed in comparable areas worldwide. The profiles of ∑OCPs and ∑PCBs in a core from a site heavily impacted by sewage discharge have highest concentrations in the surface core section indicating recent inputs. Assessment of ecotoxicological risk indicated that sediments in two sites were likely to pose potential biological adverse impact.     

Composition and distribution of organochlorine pesticide residues in surface sediments from the Wu-Shi River Estuary,Taiwan

The contamination of organochlorine pesticides (OCPs) in sediments from the Wu-Shi River estuary was investigated to evaluate the pollution potentials and distribution of OCPs in central Taiwan. A total of 19 sediment samples were collected at five sampling stations along the River estuary. The concentrations of OCPs were in the range of 0.99–14.5 ng/g-dry weight (dw) for ΣHCH (-, β-, γ-, δ-HCH), 0.46–13.4 ng/g-dw for Σcyclodiene and 0.53–11.4 ng/g-dw for ΣDDT (p,p^′-DDD, p,p^′-DDE, p,p^′-DDT). The mean concentrations of ΣHCH, Σcyclodiene and ΣDDT were 3.79, 4.87 and 2.51 ng/g-dw, respectively. The total concentrations of OCPs correspond to 1.73–71.9 μg/g-OC when normalized to TOC contents. Among the organochlorine pesticides, endosulfan sulfate, β-HCH, and p,p^′-DDD were the most dominant compounds in the sediments with the average concentrations of 1.97, 3.43 and 2.08 ng/g, respectively. Also, different contamination patterns among sampling seasons were observed. The measured concentrations of OCPs collected in spring were higher than those in autumn and winter. A linear relationship between sediment characteristics and OCP residues was also demonstrated. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the sediments from the near shore of central Taiwan.     

DDTs and other chlorinated organic pesticides and polychlorinated biphenyls pollution in the surface sediments of Keratsini harbour, Saronikos gulf, Greece

Sediment samples were collected from Keratsini harbour, Saronikos gulf, Greece and were analysed for chlorinated organic pesticides (DDTs, HCB, Lindane) and polychlorinated biphenyls (PCBs). High total DDTs values were detected in all the sediments samples ranging from 9.1 to 75.6 mug/g, dry weight. PCBs concentrations range from 47.8 to 351.8 ng/g. The results and especially the high concentrations of DDTs reflect the influence of the industrial and urban wastes in the pollution for the Keratsini harbour environment.     

PCBs, PBDEs and organochlorine pesticides in crabs Hepatus pudibundus and Callinectes danae from Santos Bay, State of São Paulo, Brazil

The occurrence of persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDE) in crabs Hepatus pudibundus and Callinectesdanae was assessed from two different places inside of the Santos Bay and Moela Island near one of the most economically important metropolitan areas in Southern Brazil. Among POPs analyzed, ∑PCBs (222-923 ng g(-1)lipid weight) and ∑DDTs (154-410 ng g(-1)lw) exhibited the highest concentrations in the crabs. ∑HCHs ranged from 10.3 to 30.9 ng g(-1)lw and were found in all individuals. Other OCPs found in lower concentration was Mirex (7.6-41.6 ng g(-1)lw) and HCB (5.83-16.9 ng g(-1)lw). ∑PBDEs (24.1 ng g(-1)lw) were only found in one male individual from the species C. danae collected near to the submarine sewage of Santos. Male crabs showed higher POP concentrations than female crabs for those two species.     

Occurrence and distribution of organochlorine residues in surface sediments of the Candarli Gulf (Eastern Aegean)

The residual levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in surface sediments collected from Candarli Gulf. Total concentrations of OCPs and PCBs in sediments ranged from 10.2 to 57.3 and 2.8 to 205 ng g⁻¹ dwt, respectively. DDTs in sediments were derived from the aged and weathered agricultural soils in 61% of the sampling stations while 39% of the sites originated from the recent DDT inputs. Their concentrations appeared to be relatively low by global standards and only sediments receiving the impact from the Bakircay River and petrochemical industry approached the sediment quality guidelines for PCBs and DDTs. Based on ERL/ERM guidelines, DDT and PCBs posed ecological risk to the bottom-dwelling consumers.     

Organochlorine pesticides (OCPs) in soils and sediments, southeast China: A case study in Xinghua Bay

This study evaluated the contamination status and distribution of organochlorine pesticides (OCPs) between Xinghua Bay and adjacent watersheds in Putian region, southeast China. Twenty-five surface soil samples and two sediment cores were collected from two watersheds and the Xinghua Bay, respectively. Results showed that the concentrations of OCPs in samples of the Mulan River Watershed (MRW), the Qiulu River Watershed (QRW), the inner bay core (IBC) and the open bay core (OBC) were in the range of 4.96-38.20 ng/g, 4.62-22.80 ng/g, 1.84-80.46 ng/g and 1.87-23.43 ng/g, respectively. The mean concentration of OCPs was in an order: IBC > MRW > QRW > OBC. The higher concentration of OCPs in recent periods may suggest that a certain amount of OCPs were still input to this area.