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1.
全氟辛酸(Perfluorooctanoic acid,PFOA)等全氟羧酸类物质(Perfluoroalkyl carboxylic acids,PFCAs)潜在的持久性、生物累积性、毒性和在环境中的广泛分布,已经引起环境研究者的广泛关注.前期研究表明除了PFCAs的直接排放,其前体物转化也是环境中PFCAs污染的主要来源.氟调醇(Fluorotelomer alcohols,FTOHs)是PFCAs重要的前体物之一.本文对FTOHs的检测方法以及不同环境介质中的环境分布进行了综述,同时重点介绍了FTOHs转化为PFCAs的机制,指出了污水处理系统中FTOHs研究的重要性,并对未来污水处理系统中FTOHs的研究进行展望.  相似文献   

2.
孙芬芬  王珊  徐玉新  乔敏 《环境化学》2014,(12):2038-2047
以跳虫Folsomia candida为受试物种,基于其28 d繁殖实验评价了不同类型包括全氟类、卤系阻燃剂类、化学镀剂类、抗菌剂类、染料类及新关注类共14种化学品的慢性毒性效应.结果表明,在所设浓度范围内,所有物质对跳虫繁殖均存在不同程度的抑制效应.抗菌剂对氯间二甲酚对跳虫慢性毒性最大,对跳虫繁殖毒性的EC50为10.0 mg·kg-1;其次为全氟类的两种物质,全氟十三烷酸、全氟十二烷酸对跳虫繁殖毒性的EC50分别为44.8、49.6 mg·kg-1;新关注类的二苯甲酮、苯并噻唑毒性也较强,对跳虫繁殖毒性的EC50分别为61.4、73.0 mg·kg-1;染料类中的直接蓝71、活性艳红KE-3B等物质的毒性均较弱,在最高浓度(500 mg·kg-1)处理下也未能达到对跳虫繁殖的半数抑制效应.  相似文献   

3.
环境水中全氟羧酸及全氟磺酸类化合物(PFCs)的分析   总被引:1,自引:0,他引:1  
本文采用Agilent 641O LC/MS/MS液相色谱-三重串联四极杆质谱建立了水中全氟辛酸(PFOA)、全氟壬酸(PFNA)、全氟癸酸(PFDA)、全氟辛烷磺酸(PFOS)、全氟十二烷酸(PFDoA)等五种全氟羧酸及磺酸类化合物在环境水中残留基测定的高效液相色谱-串联质谱方法,样品前处理采用Agilent SampliQ OPT固相萃取小柱进行浓缩净化,回收率>50%,五种化合物的线性均大于0.997,对环境水样品的检测灵敏度可达0.2 pg·ml-1.  相似文献   

4.
本文综述了目前动物模型中全氟羧酸类和全氟磺酸类前体物质的生物转化研究.绝大多数的代谢研究以大鼠和小鼠为对象,而以鱼为对象进行的研究相对较少.氟调聚丙烯酸酯类(8∶2 FTAc)和多氟烷基磷酸酯类(PAPs)均可先代谢为氟调聚醇类(FTOHs),最终代谢为全氟羧酸类(PFCAs).全氟磺酰胺类可最终代谢为全氟磺酸类(PFSAs).目前,以8∶2氟调聚醇(8∶2 FTOH)和N-乙酰全氟辛烷磺酰氨乙醇(N-Et FOSE)为主要研究物质,且工业中使用的全氟和多氟烷基物质碳链长度逐渐变短,所以有关短链物质的代谢研究也越来越多.  相似文献   

5.
近年来,全氟化合物(PFCs)如全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA,其分子结构如图1所示)已经被明确为持久性有机污染物(POPs),并在环境中普遍存在[1].由于PFCs可能具有毒性和生物积聚性,因此,对食品、饮用水、组织、血浆和全血中PFCs分析方法的建立受到越来越多的关注.  相似文献   

6.
以全氟辛烷羧酸(PFOA)和全氟辛烷磺酸(PFOS)为代表的全氟化合物(PFCs),在日用消费品和工业生产中被广泛使用,并可通过各种途径大量进入环境.在全球各类环境介质以及生物体中已经普遍检测到了PFCs的存在.目前有关水环境中PFCs的分布及归趋研究,主要针对PFOS和PFOA及其长链同系物.随着PFOS和PFOA的禁用,一系列短链同系物作为替代物质进入生产和应用领域,并最终进入环境.目前针对短链全氟化合物的分析方法报道的还较少.  相似文献   

7.
近年来,全氟化合物(PFCs)如全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA,其分子结构如图1所示)已经被明确为持久性有机污染物(POPs),并在环境中普遍存在[1].由于PFCs可能具有毒性和生物积聚性,因此,对食品、饮用水、组织、血浆和全血中PFCs分析方法的建立受到越来越多的关注.本文将讨论  相似文献   

8.
全氟化合物(PFCs)作为一类难降解的持久性污染物,由于其可能导致肝毒性、致癌性、免疫毒性、生殖毒性以及干扰内分泌等特性,近年来成为研究的热点.通常环境水样中PFCs含量较低,其中全氟磺酸类化合物(PFSAs)和全氟羧酸类化合物(PFCAs)为痕量水平,因此环境水样中PFSAs和PFCAs的分析需要建立灵敏可靠的分析方法.国内外已针对环境水样中PFSAs和PFCAs的分析开展了大量研究,但全面系统的评述其分析方法近年来的新进展鲜见报道.本文全面总结了近5年来环境水样中PFSAs和PFCAs前处理方法及检测技术的新进展,主要包含基于色谱质谱的分析方法、基于光谱的分析方法、基于酶联免疫吸附测定(ELISA)的分析方法等三类;重点对样品前处理方法和检测技术的新进展进行综述;并对各种方法的优缺点进行了比较和评述.在此基础上对其发展趋势进行展望,以期为相关研究提供参考.  相似文献   

9.
本文对北京市167对匹配母亲静脉血与脐带血中15种全氟化合物前体物质浓度水平与胎盘透过率进行了分析.研究结果表明,6∶2氟调聚磺酸(6∶2 FTS),N-甲基全氟辛基磺酰胺乙酸(NMe FOSAA)在母亲静脉血与脐带血中均以较高检出率检出(81%与74%,母亲静脉血;90%与67%,脐带血),浓度范围分别为LOD(3.00)—203.00 pg·m L-1与LOD(0.30)—46.79 pg·m L-1(母亲静脉血),LOD(3.00)—252.12pg·m L-1与LOD(0.30)—16.00 pg·m L-1(脐带血);全氟辛基磺酰胺(FOSA),N-乙基全氟辛基磺酰胺乙酸(NEt FOSAA)则在匹配血样中检出率和浓度水平较低;8∶2 FTS,N-乙基全氟辛基磺酰胺(NEt FOSA)仅在母亲静脉血中以较低检出率检出.6∶2 FTS与NMe FOSAA的母血浓度与脐带血浓度呈正相关关系,6∶2 FTS胎盘透过率高于NMe FOSAA.本研究提示了全氟化合物前体物质在人体内的胎盘转移和产前暴露情况.  相似文献   

10.
近岸海水中全氟化合物的液相色谱-离子阱质谱法测定   总被引:1,自引:0,他引:1  
建立了利用高效液相色谱-电喷雾离子阱质谱(HPLC-ESI-IT-MS/MS)测定近岸海水中多种常见全氟化合物(PFCs)的分析方法.采用固相萃取法(SPE)对海水中的PFCs净化富集,用HPLC-ESI-IT-MS/MS多反应离子监测(MRM)模式对各组分(全氟己烷磺酸、全氟辛烷磺酸、全氟辛烷磺酰胺、全氟己酸、全氟庚酸、全氟辛酸、全氟壬酸、全氟癸酸、全氟十一酸、全氟十二酸)进行测定.在最佳实验条件下,采用基质匹配标准曲线法定量,以消除海水基质的影响,8种目标化合物的检出限介于0.50—1.00 ng·L-1,9种PFCs的回收率在71.0%—130.2%之间,能满足近岸海水中多种PFCs检测的要求.青岛沿岸表层海水样品测定结果显示,全部采样站点的海水样品中均检测到≥4种PFCs,说明青岛沿岸海水中已有一定程度的PFCs污染.  相似文献   

11.
Invasive non-native species are important drivers of ecosystem change, yet the driving forces of biological invasions themselves are poorly understood. Such information is essential to ensure policies focus on the most relevant drivers, and that future scenarios capture the full range of potential outcomes for invasive non-native species. I carried out a bibliometric analysis of articles published from 2000 to 2020 that address either invasive non-native species or biodiversity and ecosystem services and that also mention 1 or more drivers of ecosystem change. I examined 5 indirect drivers (demographic, economic, governance, sociocultural, and technological) and 6 direct drivers (climate change, invasive non-native species, land-use or sea-use change, natural hazards, pollution, and resource extraction). Using the Web of Science core collection of citation indexes, I undertook searches of article titles and keywords and retrieved 27,462 articles addressing invasive non-native species and 110,087 articles dealing with biodiversity or ecosystem services. Most research to date on biological invasions as well as on biodiversity and ecosystem services has focused on anthropogenic direct drivers of ecosystem change rather than indirect drivers. Yet currently, less than 18% of articles addressing biological invasions examined drivers of ecosystem change, a similar level to that found over 20 years ago for biodiversity or ecosystem services. Knowledge of the drivers of biological invasions is limited, emphasizes tractable drivers over those that require an interdisciplinary approach, and is biased toward developed economies. Drivers generally deemed important for biological invasions, such as governance and resource extraction, accounted for less than 2% of research effort. The absence of a systematic understanding of the forces that drive invasive non-native species and how they interact means that attempts to mitigate or forecast biological invasions are likely to fail. To address biological invasions requires a much better orientation of national and international research on drivers in relation to both their actual importance as well as their policy relevance.  相似文献   

12.
For sea turtles, like many oviparous species, increasing temperatures during development threaten to increase embryonic mortality, alter offspring quality, and potentially create suboptimal primary sex ratios. Various methods are being implemented to mitigate the effects of climate change on reproductive success, but these methods, such as breeding programs, translocations, and shading, are often invasive and expensive. Irrigation is an alternative strategy for cooling nests that, depending on location, can be implemented relatively quickly and cheaply. However, multiple factors, including ambient conditions, nest substrate, and species characteristics, can influence irrigation success. Additionally, irrigation can vary in duration, frequency, and the volume of water applied to nests, which influences the cooling achieved and embryonic survival. Thus, it is critical to understand how to maximize cooling and manage risks before implementing irrigation as a nest-cooling strategy. We reviewed the literature on nest irrigation to examine whether artificial irrigation is feasible as a population management tool. Key factors that affected cooling were the volume of water applied and the frequency of applications. Embryonic responses varied with species, ambient conditions, and the timing of irrigation during development. Nest inundation was the key risk to a successful irrigation regime. Future irrigation regimes must identify clear targets, either primary or adult sex ratios, that maximize population viability. Monitoring population responses and adjusting the irrigation regime in response to population characteristics will be critical. Most studies reported on the manipulation of only one or two variables, further research is required to understand how altering multiple factors in an irrigation regime influences the cooling achieved and embryonic responses.  相似文献   

13.
Species that are strong interactors play disproportionately important roles in the dynamics of natural ecosystems. It has been proposed that their presence is necessary for positively shaping the structure and functioning of ecosystems. We evaluated this hypothesis using the case of the world's largest parrotfish (Bolbometopon muricatum), a globally imperiled species. We used direct observation, animal tracking, and computer simulations to examine the diverse routes through which B. muricatum affects the diversity, dispersal, relative abundance, and survival of the corals that comprise the foundation of reef ecosystems. Our results suggest that this species can influence reef building corals in both positive and negative ways. Field observation and simulation outputs indicated that B. muricatum reduced the abundance of macroalgae that can outcompete corals, but they also feed directly on corals, decreasing coral abundance, diversity, and colony size. B. muricatum appeared to facilitate coral advancement by mechanically dispersing coral fragments and opening up bare space for coral settlement, but they also damaged adult corals and remobilized a large volume of potentially stressful carbonate sediment. The impacts this species has on reefs appears to be regulated in part by its abundance—the effects of B. muricatum were more intense in simulation scenarios populated with high densities of these fish. Observations conducted in regions with high and low predator (e.g., sharks) abundance generated results that are consistent with the hypothesis that these predators of B. muricatum may play a role in governing their abundance; thus, predation may modulate the intensity of the effects they have on reef dynamics. Overall our results illustrate that functionally unique and threatened species may not have universally positive impacts on ecosystems and that it may be necessary for environmental managers to consider the diverse effects of such species and the forces that mediate the strength of their influence. Efectos Positivos y Negativos de un Pez Loro Amenazado Sobre Ecosistemas Arrecifales  相似文献   

14.
Two closely related forms ofOphrys insectifera were observed in the field to attract different pollinator species selectively.O. i. ssp.insectifera attracted males of two species ofArgogorytes (Sphecidae, Hymenoptera Aculeata) andO. i. ssp.aymoninii attractedAndrena combinata males (Andrenidae, Apoidea, Hymenoptera Aculeata). A third form,O. aff.i. ssp.insectifera, attracted none of these three species. Volatile compounds from flowers and inflorescences of the three forms (originating from Öland, Sweden, and Aveyron, France) were collected, using entrainment, enfleurage, and solvent extraction techniques, and identified by gas chromatography — mass spectrometry. Scent differences between the three forms were confirmed in the amounts of aliphatic hydrocarbons (C11–C19), methyl esters (C14–C18), short chain aliphatic 1-alcohols (C6–C12), and monoterpene alcohols (C10).  相似文献   

15.
A method is developed to estimate the stress at the surface in a portable wind tunnel for wind erosion studies. The boundary layer height and the pressure gradient are used in a simple expression from the Kármán Integral Momentum Equation. Values of friction velocity u * are within 10% of experimental values obtained through correlation techniques, including measurements of differential pressures with the Murdoch Turbulence Probe MTP and the X-wire, hot-wire anemometer XWA. Wind velocity and stress profiles reveal logarithmic trends and a constant stress layer near the surface in the DAWA portable wind tunnel. Realignment of the statistics with the mean wind is essential.  相似文献   

16.
Global biodiversity indices are used to measure environmental change and progress toward conservation goals, yet few indices have been evaluated comprehensively for their capacity to detect trends of interest, such as declines in threatened species or ecosystem function. Using a structured approach based on decision science, we qualitatively evaluated 9 indices commonly used to track biodiversity at global and regional scales against 5 criteria relating to objectives, design, behavior, incorporation of uncertainty, and constraints (e.g., costs and data availability). Evaluation was based on reference literature for indices available at the time of assessment. We identified 4 key gaps in indices assessed: pathways to achieving goals (means objectives) were not always clear or relevant to desired outcomes (fundamental objectives); index testing and understanding of expected behavior was often lacking; uncertainty was seldom acknowledged or accounted for; and costs of implementation were seldom considered. These gaps may render indices inadequate in certain decision-making contexts and are problematic for indices linked with biodiversity targets and sustainability goals. Ensuring that index objectives are clear and their design is underpinned by a model of relevant processes are crucial in addressing the gaps identified by our assessment. Uptake and productive use of indices will be improved if index performance is tested rigorously and assumptions and uncertainties are clearly communicated to end users. This will increase index accuracy and value in tracking biodiversity change and supporting national and global policy decisions, such as the post-2020 global biodiversity framework of the Convention on Biological Diversity.  相似文献   

17.
Use of the internet as a trade platform has resulted in a shift in the illegal wildlife trade. Increased scrutiny of illegal wildlife trade has led to concerns that online trade of wildlife will move onto the dark web. To provide a baseline of illegal wildlife trade on the dark web, we downloaded and archived 9852 items (individual posts) from the dark web, then searched these based on a list of 121 keywords associated with illegal online wildlife trade, including 30 keywords associated with illegally traded elephant ivory on the surface web. Results were compared with items known to be illegally traded on the dark web, specifically cannabis, cocaine, and heroin, to compare the extent of the trade. Of these 121 keywords, 4 resulted in hits, of which only one was potentially linked to illegal wildlife trade. This sole case was the sale and discussion of Echinopsis pachanoi (San Pedro cactus), which has hallucinogenic properties. This negligible level of activity related to the illegal trade of wildlife on the dark web relative to the open and increasing trade on the surface web may indicate a lack of successful enforcement against illegal wildlife trade on the surface web.  相似文献   

18.
Freshwater turtle populations are susceptible to declines following small increases in the mortality of adults, making it essential to identify and understand potential threats. Freshwater turtles ingest fish hooks associated with recreational angling, and this is likely a problem because hook ingestion is a source of additive mortality for sea turtles. We used a Bayesian‐modeling framework, observed rates of hook ingestion by freshwater turtles, and mortality of sea turtles from hook ingestion to examine the probability that a freshwater turtle in a given population ingests a hook and subsequently dies from it. We used the results of these analyses and previously published life‐history data to simulate the effects of hook ingestion on population growth for 3 species of freshwater turtle. In our simulation, the probability that an individual turtle ingests a hook and dies as a result was 1.2–11%. Our simulation results suggest that this rate of mortality from hook ingestion is sufficient to cause population declines. We believe we have identified fish‐hook ingestion as a serious yet generally overlooked threat to the viability of freshwater turtle populations.  相似文献   

19.
20.
Content analysis of newspaper coverage of the Florida panther   总被引:1,自引:0,他引:1  
Populations of large carnivores are declining globally, and analysis of public discourse about carnivores is useful for understanding public opinion and influences on management and policy. Portrayal of carnivores in the media affects public perceptions and support for their conservation. We conducted a content analysis of 513 articles about Florida panthers (Puma concolor coryi) published from 2003 to 2006 in newspapers with local circulation in core panther habitat in southwest Florida and papers with statewide circulation to compare the differences in the amount of coverage and portrayals of panther risks to people and property on the basis of proximity of human communities to panthers. Local papers published significantly more news articles and significantly longer news articles primarily about panthers. Articles in local and statewide papers used both episodic frames, which focus on specific occurrences (e.g., a panther sighting or predation) and thematic frames, which focus on general trends (e.g., abundance of panthers over time). Local articles more often emphasized risks that panthers might harm people, pets, or livestock than statewide papers. Our results are consistent with theory that proximity to human-carnivore conflict influences perceptions and salience of risks posed by large carnivores. Most articles mentioned panthers as a secondary topic, which we believe was a result of the relevance an endangered carnivore has in discussions of public land management, development, and regulations in Florida. Claims made by sources quoted in each article had a neutral to positive depiction of panthers, and most quotations were from federal and state agency scientists. We suggest continued use by the media of agency sources provides the opportunity for clear, concordant messages about panther management. Content analysis provides a way to monitor media portrayal of carnivores for consistency with agency outreach goals.  相似文献   

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