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1.
《环境化学》2014,(8):1429
长距离大气迁移(LRAT)使得包括有机氯农药(OCPs)在内的持久性污染物(POPs)从源区被搬运到遥远的地区.在LRAT过程中,POPs逐级发生沉降与再挥发,由于该自然过程的作用,POPs在全球范围内均有分布.冷捕获(Cold-trapping)是半挥发性POPs沉降到地表的主要途径之一,POPs由温度较高地区挥发并逐步在温度较低地区沉降累积.由于轻组分更易于再挥发,并在温度更低地区冷凝沉降,因此产生组分分馏,轻组分POPs逐渐向温度较低的极地和高山地区累积.作为沉降与再挥发过程反复作用的结果,随纬度或海拔的增加,POPs的含量与组成呈梯度性增加.  相似文献   

2.
持久性有机污染物(Persistent Organic pollutant,POPs)是指通过各种环境介质(大气、水、生物体等)能够长距离迁移并长期存在于环境中的人工合成的有机污染物。本文阐述了全球POPs的主要环境过程和各环境介质中POPs的暴露水平,探讨了作物对POPs的吸收过程、吸收机制和生态效应,并基于现有的环境多介质逸度模型和根区水质模型,分析了持久性有机污染物作物吸收过程模拟模型中存在的问题及未来的发展方向。目前,对POPs作物吸收机制及其模拟的研究较少,但随着我国对粮食安全和农业可持续发展的持续关注,这一领域的模拟研究将对科学解析POPs归趋、合理制定风险管控措施和有效确保粮食质量安全等提供重要科学支撑。  相似文献   

3.
铅是公认的神经毒物,它的神经毒性是全世界备受关注的重要公共健康问题,特别是发育早期阶段铅暴露与神经行为变化之间的关联.斑马鱼被认为是研究发育早期阶段低浓度铅暴露诱导神经行为毒性的优良模式生物.因此,本研究以斑马鱼胚胎/仔鱼为研究对象,利用Zebrabox建立的行为学效应测试方法,包括运动行为、转动行为和社交行为,系统评价发育早期阶段环境相关浓度(以电子废弃物拆解场地为例)铅暴露的神经行为毒性效应.发育正常的斑马鱼胚胎暴露在浓度为0、5、10、20μg·L~(-1)铅暴露液中直至6 dpf.铅暴露对斑马鱼胚胎/仔鱼具有发育毒性作用,包括孵化率和存活率下降,卵黄囊肿、心包囊肿和脊柱弯曲等畸形现象.在光照条件下,铅暴露对斑马鱼仔鱼的运行行为和转向行为并未产生显著影响;但是在黑暗条件下,20μg·L~(-1)铅暴露后斑马鱼仔鱼运动距离和总转向次数均显著下降,但是其行进路径角度和偏转偏好却无变化.与运动行为和转向行为不同,在黑暗条件下,铅暴露对斑马鱼仔鱼的社交行为并未产生显著影响;但在光照条件下20μg·L~(-1)铅暴露却显著改变了仔鱼的社交次数.本研究结果表明,行为学指标不仅具备足够的灵敏度可用于指示电子废弃物拆解场地铅污染的潜在风险,还能更好地服务于人类健康早期预警的需求.  相似文献   

4.
系统介绍了采用EPA8081A与8082方法进行环境样品中持久性有机污染物(POPs)分析的关键问题与对策。包括POPs的气相色谱分析与验证双柱系统,DDT与异狄氏剂在进样系统中的分解及其处理方法,应用目测识别法、手型法与透明复印胶片法等经验方法快速定性多氯联苯(PCBs)、氯丹与毒杀芬等多峰化合物,影响外标法准确定量PCBs、氯丹与毒杀芬等多峰POPs的关键因素,以及质量控制要求。提出应根据中国POPs的环境污染特点,建立相应的POPs标样库与标准图谱库,为中国的POPs污染调查与环境监测提供技术支持。  相似文献   

5.
介绍了持久性有机污染物(POPs)的定义、来源以及我国涉及POPs的工业生产与数量分布,明确氯碱工业、有机氯工业等精细化工业与垃圾焚烧厂产生的POPs成为未来的主要污染源;对统计数据进行分析指出,由于历史上POPs的应用以及排放,我国工业发达地区河段水体中普遍检出POPs,浓度为几到几十ng·L-1范围,部分流域超标;...  相似文献   

6.
南亚排放的持久性有机污染物(POPs)可随大气传输到青藏高原,然而POPs在高原多介质间的迁移与分配尚不清晰。本研究利用三级逸度模型对4种POPs(六六六α-HCH,滴滴涕p,p'-DDT,菲Phe和苯并芘Ba P)在纳木错流域的迁移与归趋进行了模拟。结果表明,大气沉降是该区域污染物的主要输入过程,而降解损失则是主要的输出途径。就最终归趋而言,土壤是POPs在纳木错流域的重要储库,其存储了大于50%的POPs。此外,湖水和沉积物分别对α-HCH和PAHs具有较强的存储能力。灵敏度分析的结果表明,环境温度、大气中POPs的浓度及其理化性质是影响POPs在环境中分布的关键参数。本研究明确了纳木错流域不同POPs的迁移方向和归趋特征,这将为青藏高原生态安全评估提供科学依据。  相似文献   

7.
持久性有机污染物在食物链中积累与放大研究进展   总被引:3,自引:0,他引:3  
研究持久性有机污染物(Persistent organic pollutants,POPs)在食物链中的积累与放大是进行环境风险评估和有效污染控制的生态学基础.本文综述了POPs的基本特征,POPs在食物链中的生物积累与放大的机制、影响因素以及POPs在食物链中积累与放大的模型等的研究进展.国外学者对POPs在水生食物链的积累与放大方面研究较多,并提出了较为完善的预测模型,而有关POPs在陆生食物链中的生物积累与放大的研究报道较少.大部分学者并未对完整食物链进行过系统而完整的研究.与国外相比,国内学者对POPs在水生陆生食物链中的生物积累、生物放大和预测模型探讨较少.目前POPs对环境和人体健康危害越来越严重,开展对POPs在食物链中积累、放大及相关预测模型更深入更完整的研究,已成为当前生态学和环境科学研究的重点课题和前沿领域.  相似文献   

8.
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   

9.
为比较直接经水体与经营养传递的2种镉(cadmium,Cd)暴露方式对方斑东风螺(Babylonia areolata)不同组织Cd蓄积和毒性的差异,采用室内模拟法,将螺暴露于含Cd水体(Cd2+:100μg·L-1)或喂食含Cd饵料(牡蛎,34.56μg·g-1以干质量计,先经水体100μg·L-1Cd2+暴露达平衡)30d后再进行15d净化。结果显示,暴露期间,除食物相组螺胃肠道Cd浓度在第10天极显著高于对照组,但随后迅速下降外,其他各组织在2种途径及胃肠道在水相暴露时Cd的浓度均逐渐上升,暴露30d后肝胰脏中Cd浓度最高;净化期,螺鳃中Cd排出率较高,胃肠道与肝胰脏的排出率较低,至净化期末除食物相组鳃中Cd浓度与对照组无显著差异外,2种处理中其他各组织Cd浓度仍显著高于对照组。2种暴露途径中金属硫蛋白(metallothionein,MT)浓度仅在螺肝胰脏中逐渐增加,且与Cd的蓄积呈显著线性正相关。与食物相组相比,水相Cd暴露引起螺肝胰脏脂质过氧化水平(lipid peroxidation,LPO)更高,且内脏团中Cd与其亚细胞成分的金属敏感组分结合的百分比也更高。结果表明,Cd通过营养传递对螺产生的毒性较水体直接暴露低,但摄食是螺蓄积Cd的主要途径;净化后除鳃外水相暴露组螺各组织Cd的排出率较低;因此为了健康养殖与食用安全,东风螺工厂化养成时对饵料与水体Cd浓度的监测均应引起足够的重视。  相似文献   

10.
采用常规、含Cd~(2+)和含Pb~(2+)的马丁氏培养基,对云南省会泽县废弃铅锌矿区和非矿区小花南芥(Arabisalpine)根际真菌进行分离,将分离的菌株接种到含不同浓度(0、0.05、0.5、5mmolL~(-1))Cd~(2+)的马铃薯葡萄糖培养液中,比较废弃铅锌矿区和非矿区小花南芥根际真菌的镉耐性.结果表明:Cd~(2+)显著抑制铅锌矿区和非矿区小花南芥根际真菌的生长;常规、含Cd~(2+)和含Pb~(2+)的马丁氏培养基分离的铅锌矿区小花南芥根际真菌Cd~(2+)的生长半数抑制浓度(EC50值)平均值和最大值均明显大于非矿区,表明铅锌矿区小花南芥根际真菌对Cd~(2+)的耐性强于非矿区;3种培养基分离的真菌中,含Cd~(2+)培养基分离的铅锌矿区小花南芥根际真菌对Cd~(2+)的耐性最强.表3参26  相似文献   

11.
12.
《Ecological modelling》2004,179(3):405-416
The fate of persistent organic pollutants (POPs) in aquatic ecosystems is intimately linked to the cycling of organic matter. In this paper, we present a model of the effect of organic matter decomposition on the distribution of persistent organic pollutants in sediments. The model predicts a diagenetic (sediment-ageing) magnification of chemical concentrations in sediments enriched with labile organic matter. We predict two- to four-fold diagenetic magnification across a wide range of realistic parameter values, and higher levels (up to 20-fold) for labile organic matter in systems with low burial rates (i.e., residence times on the order of years). As an illustration, we apply our model to understand the fate of waste organic matter and associated PCBs discharged by marine fish farms. The available data support both the spatial pattern (as a function of burial rate) and the range of sediment PCB concentrations predicted by our model. This model explains why equilibrium models fail to predict the very high sediment-water partitioning coefficients often observed in the field. Effectively, diagenetic processes impose an additional biomagnification step at the bottom of the detritus-based food web, increasing the exposure to POPs of organisms at higher trophic levels.  相似文献   

13.
浙江省废水排放增长的EKC曲线特征分析   总被引:4,自引:0,他引:4  
选取浙江省1985~2004年经济和废水排放数据,通过分析经济因子与废水排放之间的相互关系,建立浙江省废水排放的库兹涅茨曲线模型。结果表明:浙江省废水排放与人均GDP的演替轨迹呈现显著的环境库兹涅茨曲线特征,1985~2004期间处于曲线的上升阶段。浙江省废水排放总量的EKC曲线理论转折点为人均GDP约34 305元,相应的废水排放总量峰值为35亿t,预测转折点出现的时间为2007年左右。工业废水排放量正处于EKC曲线的转折点附近,而生活废水排放量目前正处于EKC曲线加速上升的阶段,转折点出现的时间为2007年左右,对应的生活废水排放量的峰值为15亿t,是2004年生活废水排放量(11.6亿t)的1.3倍,形势非常严峻,应该引起重视。因此,十一五期间,浙江省尤其要注重对生活废水排放的控制和治理,并且保持较高的治理投入。  相似文献   

14.
This paper examines the relationship between climate change awareness and household behavior by testing whether Al Gore's documentary An Inconvenient Truth caused an increase in the purchase of voluntary carbon offsets. I find that in the two months following the film's release, zip codes within a 10-mile radius of a zip code where the film was shown experienced a 50 percent relative increase in the purchase of voluntary carbon offsets. During other times, offset purchasing patterns for zip codes inside the 10-mile radius were similar to the patterns of zip codes outside the 10-mile radius. There is, however, little evidence that individuals who purchased an offset due to the film purchased them again a year later.  相似文献   

15.
We used satellite telemetry to study behavior at foraging sites of 40 adult female loggerhead sea turtles (Caretta caretta) from three Florida (USA) rookeries. Foraging sites were located in four countries (USA, Mexico, the Bahamas, and Cuba). We were able to determine home range for 32 of the loggerheads. One turtle moved through several temporary residence areas, but the rest had a primary residence area in which they spent all or most of their time (usually >11 months per year). Twenty-four had a primary residence area that was <500 km2 (mean = 191). Seven had a primary residence area that was ≥500 km2 (range = 573–1,907). Primary residence areas were mostly restricted to depths <100 m. Loggerheads appeared to favor areas with larger-grained sediment (gravel and rock) over areas with smaller-grained sediment (mud). Short-term departures from primary residence areas were either looping excursions, typically involving 1–2 weeks of continuous travel, or movement to a secondary residence area where turtles spent 25–45 days before returning to their primary residence area. Ten turtles had a secondary residence area, and six used it as an overwintering site. For those six turtles, the primary residence area was in shallow water (<17 m) in the northern half of the Gulf of Mexico (GOM), and overwintering sites were farther offshore or farther south. We documented long winter dive times (>4 h) for the first time in the GOM. Characterizing behaviors at foraging sites helps inform and assess loggerhead recovery efforts.  相似文献   

16.
邻苯二甲酸酯降解细菌的多样性、降解机理及环境应用   总被引:1,自引:0,他引:1  
邻苯二甲酸酯(phthalic acid esters,PAEs)是一类对人体内分泌系统有干扰作用的持续性有机污染物(persistent organic pol utants,POPs)。PAEs在环境介质如水体、底泥和土壤中长期赋存会对生物体产生毒害效应,其分布广、浓度高和难降解等特点是限制有效环境治理的主要因素。作为环境的重要组成部分,微生物对污染物有很强的适应能力和高效的降解能力,这为PAEs的生物修复提供了可能。与物理化学修复法相比,微生物修复技术具有可控性强、修复面广和灵活性高等优势。本文综述了已报道的大部分PAEs降解细菌的种类及其代谢机制,并分析了其在PAEs污染水体和土壤修复中的应用现状与前景,以期为PAEs环境行为与生物修复研究提供参考。  相似文献   

17.
利用土壤环境资料中关于锡元素的32335个数据,癌死亡调查资料787080例,研究了胃癌、食管癌、肝癌、宫颈癌、肺癌、大肠癌、白血病、鼻咽癌、乳腺病死亡率与人鲜生活区土壤环境中锡元素的关系,结果表明。食管癌死亡率与生活区土壤中锡元素质量分数的相关性显著,肝癌、宫颈癌、鼻咽癌死亡率与生活区土壤中锻元素质量分数的相关性极显著,而胃癌、肺癌、大肠癌、白血病、乳腺癌死亡率与生活区土壤中锡元素质量分数的相共性下显著。  相似文献   

18.
Addressing the environmental risk of persistent organic pollutants in China   总被引:1,自引:0,他引:1  
The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been listed as POPs in the Stockholm Convention. The POPs Research Center was established in Tsinghua University in the same year when the Convention was adopted. In the last ten years, much work has been done by Chinese researchers to understand the environmental risk of POPs in China. This article aims to review the recent research progress of our POPs Research Center and some other Chinese researchers?? studies in addressing the environmental risk of POPs, including the priority screening and inventory study of POPs, monitoring and modeling of POPs pollution and exposure, and environmental risk assessment and modeling of POPs. Although great advances in addressing the environmental risk of POPs have been made in recent years, we are still facing quite a few problems, such as data scarcity and uncertainty in environmental risk assessment of POPs. The study on the effect of POPs mixtures is in its infancy and currently POPs are usually assessed from legal perspective by risk assessment of single chemicals. These problems should be well addressed by further efforts. Further studies should also be taken in future to study environment risk of POPs by considering aspects of coupled dynamics between climate processes and POPs. Such sound scientific, riskbased information can support decision-making aiming to effectively minimize the risk level of POPs.  相似文献   

19.
Lead (Pb) is a well-studied environmental contaminant that has many negative health effects, especially for children. Both racial/ethnic and income disparities have been documented with respect to exposure to Pb in soils. The objectives of this study were to assess whether soil Pb concentrations in rural and urban areas of South Carolina USA, previously identified as having clusters of intellectual disabilities (ID) in children, were positively associated with populations of minority and low-income individuals and children (≤6 years of age). Surface soils from two rural and two urban areas with identified clusters of ID were analyzed for Pb and concentrations were spatially interpolated using inverse distance weighted analysis. Population race/ethnicity and income-to-poverty ratio (ITPR) from United States Census 2000 block group data were aerially interpolated by block group within each area. Urban areas had significantly higher concentrations of Pb than rural areas. Significant positive associations between black, non-Hispanic Latino, individuals and children ≤6 years of age and mean estimated Pb concentrations were observed in both urban (r = 0.38, p = 0.0007) and rural (r = 0.53, p = 0.04) areas. Significant positive associations also were observed between individuals and children with an ITPR < 1.00 and Pb concentrations, though primarily in urban areas. Racial/ethnic minorities and low ITPR individuals, including children, may be at elevated risk for exposure to Pb in soils.  相似文献   

20.
Qin  Qilin  Xu  Xijin  Dai  Qingyuan  Ye  Kai  Wang  Chenyang  Huo  Xia 《Environmental geochemistry and health》2019,41(1):93-123
Environmental Geochemistry and Health - This paper reviews the concentrations of persistent organic pollutants (POPs) in atmosphere of an electronic waste (e-waste) recycling town, Guiyu, in...  相似文献   

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