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1.
以全氟辛烷磺酰基化合物(Perfluorooctanesulphonate,PFOS)为代表的全氟化合物是一类新型持久性环境污染物,因在生产生活中的广泛使用而长期存在于环境中,目前已成为一种全球性污染物.近年来对PFOS等物质的污染检测已经从水土环境转向了生物有机体,在鸟类、鱼类、海洋动物、哺乳动物、人类等各个层次上的生物均已开始了广泛的检测分析.北美、欧洲、日本、中国等国是受此类物质污染程度较高并且研究报道较多的区域.论文总结了PFOS在上述地区不同生物体和不同人群的污染现状及暴露水平,为全面了解并控制PFOS污染提供了基础依据.  相似文献   

2.
天津市郊农田土壤中有机氯农药残留的局地分异   总被引:13,自引:0,他引:13  
在天津3处典型污灌与非污灌农田各采集了10个表土样品,测定了其中α-HCH,β-HCH,γ-HCH,δ-HCH、p,p'-DDE,p,p'-DDD,p,p'-DDT和p'-DDT等8种有机氯农药含量,籍以研究该地区有机氯农药在地块中的局部分异。结果表明,所研究地块中两类化合物含量均表现出显著的非均一特征。其中污灌土地中的(DDT)以及污灌农田中的HCH含量都具有与灌溉方向密切相关的空间分布特征。这样的规律性空间变异导致他们的空间波动幅度高于其他地块。鉴于上述趋势性和非趋势性空间分异,在开展相关时人有必要在目标地块中采集重复样或混合样。  相似文献   

3.
为了更深入的了解和阐释手性有机氯农药在土壤中的转化和环境归趋,采用实验室室内避光培养方法,研究了o,p'-DDT及o,p'-DDD 2种手性有机氯农药的外消旋体在水稻土厌氧培养体系和菜园土好氧培养体系中的选择性降解情况。为了更好的利用土壤中土著微生物的活性,我们选择了厌氧微生物比较丰富的水稻土和好氧微生物丰度比较高的菜园土来做培养实验。结果表明实验体系中o,p'-DDT及o,p'-DDD在水稻土和菜园土中的降解均没有明显的对映体选择性。这一结果与2种手性化合物不同对映体在自然环境中的含量普遍具有差异性有所不同,说明野外环境条件和室内模拟实验条件的差异会影响手性化合物的降解选择性。在2种体系中,o,p'-DDT的降解速率均高于o,p'-DDD的降解速率。这与以前的研究报道一致,DDD比DDT更难降解。通过2个体系的比较,发现DDT的降解速率在厌氧体系中高于好氧体系,而DDD的降解速率与之相反,好氧体系高于厌氧体系。这应该与DDT和DDD 2种化合物的化学结构及2种土壤中微生物群落的差异有关。对于厌氧体系中的2种水稻土,采自中山的水稻土中DDT的降解速率高于江门的水稻土,这应该与中山水稻土有机质含量高于江门的水稻土有关。有机质含量的高低直接反映了土壤中微生物的多少,进而会影响污染物的降解速率。研究发现本实验所用水稻土和菜园土总有机碳含量偏低可能是影响2种化合物的对映体无降解选择性的因素之一。此外,由于本研究采用缓冲溶液将pH 调控在中性,因此本文的土壤 pH 对降解选择性的影响仍有待进一步研究。本研究中好氧体系和厌氧体系对目标物的降解选择性无明显差异。  相似文献   

4.
有机氯农药(Organochlorine pesticides,OCPs)曾在全世界被大量使用,即使禁用多年,仍能在各种环境介质中被广泛检出,对生态环境和人体健康存在着潜在的威胁。因此OCPs的环境迁移和归趋一直是该领域的研究热点。树皮是一种天然的被动采样器,能够很好的反映出大气有机物长期的污染程度。本文简要论述了树皮作为被动采样器在大气污染物监测研究中应用的优势,并对OCPs在树皮中的残留浓度、特征及影响其富集的因素进行了探讨,最后特别针对具有手性的OCPs在树皮中的对映体选择性特征进行了评述。  相似文献   

5.
有机氯农药(Organochlorine pesticides, OCPs)曾在全世界被大量使用,即使禁用多年,仍能在各种环境介质中被广泛检出,对生态环境和人体健康存在着潜在的威胁。因此OCPs的环境迁移和归趋一直是该领域的研究热点。树皮是一种天然的被动采样器,能够很好的反映出大气有机物长期的污染程度。本文简要论述了树皮作为被动采样器在大气污染物监测研究中应用的优势,并对OCPs在树皮中的残留浓度、特征及影响其富集的因素进行了探讨,最后特别针对具有手性的OCPs在树皮中的对映体选择性特征进行了评述。  相似文献   

6.
Human breast milk samples, collected during April 2007 in Tabriz, Iran, were analyzed for organochlorine (OC) pesticides, such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), α, β, and γ-hexachlorocycloexane (HCH) isomers and six polychlorinated biphenyls (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153, and 180). Organochlorine pesticides and OCB were both prevalent in the samples of human breast milk. Average concentrations of HCB, DDT, HCH, and PCB were 1020, 1930, 1660, and 690 ng g?1 lipid weight, respectively. A positive correlation was observed between concentration of OC in human breast milk and mothers age with primiparae. Women having higher OC concentrations than multiparae women suggests that these parameters influence the OC burden in lactating women. The estimated tolerable daily intakes (TDIs) of HCH, HCB and PCB solely from human breast milk were 100, 46, and 43% of samples, respectively, exceeding guideline thresholds given as TDI proposed by Health Canada. Although high daily intakes may raise concerns for possible adverse effects of OC, women in Tabriz are recommended to breastfeed due to the numerous advantages for mother and child.  相似文献   

7.
ABSTRACT

An ultrasonic extraction – gas chromatography – electron capture detector analytical method was used to measure the concentration and types of organochlorine (OC) pesticides in sediment to obtain a better understanding of the characteristics and hidden ecological risks associated with OC pesticide exposure in surface sediment of the Qingshitan Reservoir. Fifteen types of OC pesticides were detected in the sediment, and the sum concentration of these chemicals was in the 149.32–490.19 ng/g range (mean value: 319.39 ng/g). The concentrations of detected OC pesticides occurred in the following order: hexachlorohexanes (HCHs) (mean value: 200.17 ng/g) > DDTs (mean value: 36.92 ng/g) > heptachlors (mean value: 32.74 ng/g) > methoxychlor (mean value: 24.13 ng/g). There was a 100% detection rate for HCH isomers, and their concentrations occurred in the following order: β-HCH > δ-HCH > γ-HCH > α-HCH. β-HCH was the main component of HCHs. Ratios between α-HCH/γ-HCH and β-/(α+γ)-HCH were used to investigate the sources of pollution. Most of the surveyed areas were polluted by lindane, which originated from past pesticide residue usage, and no new inputs of HCHs were found. DDT was the major component of the DDTs, and accounted for 52%–87% of the DDTs. The ratios of (DDE+DDD)/DDT at all sample collection points were less than 1, indicating that degradation rate of DDTs in sediment was low and there was a new input of DDTs in these surveyed areas. The ratio of DDD/DDE was less than 1 at most of the sample collection points, indicating that the degradation of DDT in the sediments primarily took place under aerobic conditions. Comparison of OC pesticide residual levels in the underwater sediment collected at the Qingshitan Reservoir to other states and countries showed the pollution level of these chemicals of the Qingshitan Reservoir was relatively high. The ecological risk was assessed based on guideline values of effects range-low (ERL) and effects range-medium (ERM). The results showed that DDD, DDE, DDTs and endrin residues in the sediment posed a moderate ecological risk, but DDT and γ-HCH showed high ecological risk. These OC pesticides might adversely affect biological systems, and need to be addressed.  相似文献   

8.
Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).  相似文献   

9.
A systematic survey of organochlorine pesticides (OCPs) including hexachlorocyclohexane isomers (α-HCH, β-HCH, γ-HCH, δ-HCH and ΣHCH) and dichlorodiphenyltrichloroethane metabolites (p,p′-DDT, p,p′-DDE, o,p′-DDT, p,p′-DDD and ∑DDT) in soils along the north coastal areas of the Bohai Sea, China, has been lacking. In this study, 31 representative surface soil samples were collected along the north coastal and riverine areas of the Bohai Sea to characterise the potential for adverse effects of ∑HCH, ∑DDT and their individual isomers and transformation products. Concentrations of ΣHCH and ΣDDT in soils ranged from less than the limit of detection (1 ng · g?1 dw (mean: 3.5 ng · g?1 dw) and2 ng · g?1 dw (mean: 1.7 × 101 ng · g?1 dw), respectively. Compared with studies of OCPs in soils from other locations, concentrations of HCHs and DDTs observed in this study were moderate. Concentrations of OCPs observed in soils were generally less than proposed reference values. HCH residues were a mixture of historical technical HCH and current lindane sources. The pattern of DDTs was consistent with historical releases of technical DDTs. Selected soil physicochemical properties did not explain the sorption and/or partitioning of HCHs or DDTs.  相似文献   

10.
深圳湾典型有机氯农药的生物累积及其人体健康风险   总被引:1,自引:2,他引:1  
位于深圳与香港之间的深圳湾是一个典型的亚热带海湾,在过去的二、三十年间,海湾的生态环境发生了巨大变化.为了更好地理解深圳湾有机氯农药(OCPs)的污染现状及其生物累积规律,于2004年2月采集了该海域23个鱼类、虾类、蟹类生物样品,分析了其体内滴滴涕(DDT)、六六六(HCH)和氯丹(CHL)各组分的含量,并对其人体健康风险进行了初步评价.结果表明,深圳湾海域鱼类DDTs、HCHs和CHLs含量范围分别为1.84~286.83、0.08~1.85、0.45~118.81ng·g-1ww(鲜重),肉食性鱼类OCPs含量通常较高;与其它海区相比,深圳湾海域水生生物体中DDTs的含量相对较高,部分鱼类样品中DDTs含量超过我国海洋生物质量国家标准(GB18421-2001)的二级标准,HCHs和CHLs则相对较低;生物体中DDTs、HCHs、CHLs的含量与其脂含量呈显著正相关(p<0.01);鱼类中DDTs、HCHs和CHLs的危害指数(HR)分析显示,目前食用深圳湾鱼类对人体正常健康(非癌症)基本无影响,但却存在潜在的致癌风险.  相似文献   

11.
Samples of groundwater, river water, river sediment, paddy soil, rice seeds, hen eggs, fish, umbilical cord blood, and newborn meconium were collected from October 2002 to October 2003 near a large site in China used for the disassembly of obsolete transformers and other electronic or electrical waste. Six indicator PCB congeners, three non-ortho dioxin-like PCB congeners, and six organochlorine pesticides were determined in the samples by GC with electron capture detector. The results demonstrated that the local environment and edible foods had been seriously polluted by toxic PCBs and organochlorine pesticides. The actual daily intakes (ADIs) of these pollutants were estimated for local residents living in the area. The intake data showed that the contents of PCBs in these local residents were substantial, as the ADI estimates greatly exceed the reference doses set by the World Health Organization and the United States Agency for Toxic Substances and Disease Registry. The presence of the indicator PCB congeners in the cord blood and the meconium samples, as well as significant correlations (r 2 > 0.80, p < 0.05) between these levels, suggests a potential biotransfer of these indicators from mothers to their newborns. This preliminary study showed that obsolete transformers and other electronic or electrical waste can be an important source for the emission of persistent organic pollutants into the local environment, such as through leakage, evaporation, runoff, and leaching. Contamination from this source appears to have reached the level considered to be a serious threat to environmental and human health around the disassembly site.  相似文献   

12.
综述了持久性有机污染物(POPs)的生物降解途径,以及国内外在外生菌根真菌降解POPs方面的研究进展,阐述了其机制与优势.根据作用的微生物和环境条件的不同,POPs如PCBs、DDT等可以通过脱氯或开环等途径生物降解.外生菌根真菌能降解多种POPs,具有较大的潜力.图2表2参30  相似文献   

13.
为研究3种典型有机氯农药(%-六六六、p,p'-DDT和七氯)低浓度暴露对锦鲤幼鱼的雌激素效应及其体内富集效应,将锦鲤幼鱼暴露于有机氯农药的6个浓度组中进行20 d慢性毒性试验,测量血清中游离钙和蛋白结合磷含量及体内各组织有机氯农药残留。结果表明,在低浓度暴露20 d后,锦鲤幼鱼血清中游离钙和蛋白结合磷含量均随暴露浓度增加而呈先增后减之势,产生了明显的雌激素效应。p,p'-DDT在鱼体各组织中的富集能力远高于%-六六六和七氯;p,p'-DDT主要在鱼油中富集,其次为鱼肝、鱼鳃和鱼皮;%-六六六和七氯主要在鱼肝中富集,其次为鱼皮、鱼鳃和鱼油;3种有机氯农药在鱼肉中的富集相对较少。  相似文献   

14.
Organochlorines (including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs)) were analysed in 10 surface sediment samples collected from the Bahiret el Bibane lagoon, which is one of the most productive lagoons and one of the most important active commercial fish traps in the southern Tunisia. The aim was to obtain information concerning the recent deposition of these compounds in this area, together with the levels, the distribution and any potential biological risk. Total concentrations of OCPs and PCBs in the sediments ranged from below the limit of detection (?1 and from 29.5 to 88.2?ng?g?1?dw, respectively. The spatial distribution of PCBs suggested that the sources of these contaminants are probably located outside the lagoon and are transported by water currents and atmospheric deposition. Compared with some other regions of the world, the Bahiret el Bibane lagoon exhibited low to moderate levels of PCBs and OCPs. According to established sediment quality guidelines, PCBs and Lindane at most of the study sites would be more concerned for the ecotoxicological risk in the Bahiret el Bibane lagoon. The results of this study could provide a useful aid for the sustainable marine management of the region.  相似文献   

15.
Abstract

In this study, we investigated the potential for reductive dechlorination of 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) by municipal sewage sludge adapted to 2,4-DCP at different concentrations. 2,4-DCP was completely dechlorinated within 4 weeks. After 18 weeks' incubation, 2,4,6-TCP was also completely dechlorinated and the residue of PCP was 0, 44.46, 51.96% at 0.5, 5, and 50 μg ml1 respectively. the 2,4-DCP adapted communities initially removed the ortho-chlorine from PCP of 5.0, 50 μg ml1, following an ortho < para < meta order of chlorine removal. Intermediate products were 3,4,5-TCP, 3,5-DCP, 3-CP (3-chlorophenol), phenol, benzoate and hexanoic acids, whereas PCP (0.5 μg ml1) indicated a preference for meta-chlorine removal. the intermediate product of 2,4,6-TCP at three concentrations were 2,4-DCP, phenol, benzoate and hexanoic acid. These products were identified by GC-MASS spectrometry. the effects of supplements, including sodium citrate (0.08 mM), sodium pyruvate (0.18 mM), sodium sulphate (0.14 mM) had a direct stimulatory effect on the dechlorination of 2,4,6-TCP and PCP after treatment for 4 weeks, but dechlorination was inhibited after 8 weeks.  相似文献   

16.
Surface soil and sediment samples were collected from the surroundings of Lila stream, which passes through the obsolete pesticides dumping area Kalashah Kaku near Lahore city, to evaluate the residual levels of 19 organochlorine pesticides (OCPs), their distribution and potential sources. OCPs followed the order: ∑ DDT>∑ HCH>dicofol>endrin>heptachlor>dieldrin. Ratios of β to γ-HCH highlighted an old source of technical HCH in the study area, whereas the predominance of p, p′-DDT and p, p′-DDE indicated presence of technical DDT in surface soils. Factor analysis based on principal component analysis identified the origin of OCPs from industrial activities in Kalashah Kaku and waste dumping from Ittehad Chemical Industries via open drains into Lila stream. Greater levels of DDTs and HCHs above quality guideline pose potential exposure risk to biological organisms, safety of agricultural products and human health in the surrounding of Lila stream.  相似文献   

17.
华北典型污灌区有机氯农药残留特征及健康风险评价   总被引:2,自引:0,他引:2  
在我国华北地区由于水资源的匮乏及农业生产的需要,采用污水灌溉与施用有机氯农药(OCPs)结合的农业管理方式普遍存在。大量OCPs则被引入到当地环境中,进而可能对该地区的居民产生潜在的健康风险。本研究分析石家庄市汪洋沟污灌区OCPs的残留状况,探讨污水灌溉条件下土壤-作物系统OCPs残留对土壤质量影响,并评价经口摄入及皮肤接触两种暴露途径下对人体产生的健康风险。结果表明:汪洋沟污灌区地表水、沉积物、土壤和玉米籽粒中检出了14种OCPs,其平均残留浓度分别为36.5 ng·L~(-1)、62.9 ng·g~(-1)、57.3 ng·g~(-1)和27.0 ng·g~(-1),滴滴涕(DDTs)是其最主要的污染物,占OCPs的73%以上,其次是六六六(HCHs)和甲氧滴滴涕。р,р'-DDT是DDTs的最主要成分,其主要来源于污水灌溉或近期DDTs的使用。γ-HCH是环境HCHs残留的主要成分,其主要来源于林丹的输入和使用。此外,在该地区污灌条件下OCPs残留对土壤中C、N循环及有机S的矿化产生一定的负面影响。研究区OCPs残留对人体产生的非致癌风险和致癌风险均不超过控制标准,但经口摄入所引致的非致癌风险应予以关注,其中р,р'-DDT与γ-HCH为主要风险物质。  相似文献   

18.
十溴联苯醚(BDE-209)是目前唯一仍在全球范围内广泛使用的多溴联苯醚阻燃剂,其环境行为及生物效应逐渐成为环境污染领域研究的热点。选用2(LD组)、10(MLD组)、50(MHD组)及250μg.L-1(HD组)4个浓度的BDE-209作用于紫红笛鲷,探讨BDE-209对紫红笛鲷鳃抗氧化酶(SOD、CAT及POD)活性和MDA含量的影响。结果显示:BDE-209可以显著促进SOD和CAT活性,且随着暴露时间延长CAT活性呈现逐渐增加的趋势。暴露7d后,MLD组SOD活性达到最高68.31U.mg-1,是对照组(CK)的5.50倍,HD组CAT活性达到6.31U.mL-1,其次为MHD组的5.96U.mL-1。BDE-209对鳃POD活性呈现先促进后抑制的作用,暴露3d时各浓度POD活性均显著高于CK组(P<0.05);7d时各浓度POD活性则受到显著抑制(P<0.05),清水恢复15d后各浓度组与CK组没有显著差异(P>0.05)。暴露期间各浓度组MDA含量均显著高于CK组(P<,并且随暴露时间延长呈现先增加后减少的趋势,7d后HD组MDA含量达到最高,为6.99nmol.mg-1,清水恢复15d后,LD和MLD组MDA含量与CK组没有显著性差异(P>0.05)。以上结果表明:BDE-209可以诱导紫红笛鲷产生氧化应激效应,CAT和SOD则在氧自由基清除中发挥作用。  相似文献   

19.
Distribution and equilibrium partitioning of metals (Cd, Cu, Cr, Fe, Ni, Pb, Mn, and Zn) between pore water and surface sediments at the Ilaje coast of Ondo State, Nigeria, were studied. The Ilaje River can be one of the interesting research locations because of its economic nature and history of oil pollution. Seasonal variations were observed to investigate possible variations in the availability of metals for organisms throughout the year. The concentrations in both sediments and pore water during the dry and wet seasons were as follows: Cu?>?Fe???Mn?>?Pb?>?Ni?>?Cr?>?Cd?>?Zn. The pore water–sediment partition coefficient (K p) showed that Zn and Cd were highly mobile while Fe and Cu have restricted mobility. Dissolved organic carbon (DOC) in pore water had a strong influence on mobility and bioavailability of all the metals (p?K oc), increased levels of Fe and Cu were linked to lithological origin. Concentrations of Pb and Ni were associated with petroleum-related sources. The significance of the field-based techniques for ecotoxicological purposes is discussed.  相似文献   

20.
Butyltin compounds (BTs) and organochlorine residues (OCs) were determined in green mussel (Perna viridis L.) collected along the coastal waters of India in 1994 and 1995 to elucidate their contamination levels and distribution. BTs were detected in all of the mussel samples, ranging from 2 to 378 ng/g wet wt, which indicated that BTs are widely distributed, with elevated concentrations in intense boating areas. BTs concentrations in green mussels were lower than those reported for developed nations as well as developing countries such as Thailand. Concentrations of OCs were much lower than those of BTs. Among OCs examined, DDTs were found to be greatest, followed by HCHs, PCBs, CHLs and HCB. Considering the fact that the usage of tributyltin (TBT), DDTs and HCHs are not controlled in India, their contamination in the aquatic environment may increase unless regulatory measures are imposed. To our knowledge, this is a first report on the detection of BTs in Indian mussels.  相似文献   

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