首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Exposure to long-range transported industrial chemicals, climate change and diseases is posing a risk to the overall health and populations of Arctic wildlife. Since local communities are relying on the same marine food web as marine mammals in the Arctic, it requires a One Health approach to understand the holistic ecosystem health including that of humans. Here we collect and identify gaps in the current knowledge of health in the Arctic and present the veterinary perspective of One Health and ecosystem dynamics. The review shows that exposure to persistent organic pollutants (POPs) is having multiple organ-system effects across taxa, including impacts on neuroendocrine disruption, immune suppression and decreased bone density among others. Furthermore, the warming Arctic climate is suspected to influence abiotic and biotic long-range transport and exposure pathways of contaminants to the Arctic resulting in increases in POP exposure of both wildlife and human populations. Exposure to vector-borne diseases and zoonoses may increase as well through range expansion and introduction of invasive species. It will be important in the future to investigate the effects of these multiple stressors on wildlife and local people to better predict the individual-level health risks. It is within this framework that One Health approaches offer promising opportunities to survey and pinpoint environmental changes that have effects on wildlife and human health.  相似文献   

2.
Galassi  S.  Provini  A.  Garofalo  E. 《Hydrobiologia》1992,(1):639-647
Sediment analysis in three Italian subalpine lakes, very close to each other and exposed to different anthropogenic pressure, was used to assess the risk from organic pollutants, including some very persistent and widespread micropollutants (PCB, DDT, PAH) as well as known local pollutants. Additionally, a wide-spectrum characterization of organic compounds by GLC-MS analysis allowed the detection of other classes of chemicals. The contamination levels were related to long distance transport and to local sources of pollution in the watershed. PAH, PCB and organochlorine pesticide levels agree with the load calculated from atmospheric depositions. Local sources of pollution are responsible for the contamination by aliphatic hydrocarbons and tris(monochloroisopropyl)-phosphate (TCIPP); these compounds were found only in the two most urbanized basins. Heavy contamination by TCIPP was found in both water and sediments; water concentrations are considered hazardous for drinking purposes. This study shows that local contaminants, not yet included in any priority list, may single; out as a major environmental concern.  相似文献   

3.
4.
Metal pollution in the fluvial sediments of the rivers has become a severe problem throughout the world. Lower valleys with agricultural land are usually receiving diverse contaminants from various sources that are characterized by constant, bioaccumulative and harmful contaminants. One example is of the Beas river (India) which shows the distribution, contamination, and pollution status of metals in the sediments. In the present study, a cluster analysis and principal component analysis were conducted to assess the impact of anthropogenic activities in sediment metals. Results of contamination factor indicate that there is low contamination, whereas enrichment factor showed that 28.5% metals showed significant pollution during pre-monsoon season, 42.8% metals showed moderate to high pollution during post-monsoon season, and 42.8% metals showed moderate to extreme pollution during the winter season. Pollution index and modified pollution index showed that sediments in the winter season are slightly and critically polluted. The ecological risk factors indicate that 23.8% metals posed moderate to high ecological risk in the sediments.  相似文献   

5.
The lower six miles of the tidal portion of the Passaic River (Study Area) has been heavily industrialized since the mid-1800s. The objectives of this study were to: quantify the present extent and magnitude of chemical contamination in surface sediments from the Study Area; evaluate the contamination in the Study Area relative to a reference area and surrounding regional waterways; assess the potential for adverse effects to aquatic organisms; and identify spatial gradients in concentrations that may indicate potential point-sources of chemicals. Because existing ecological communities center primarily on intertidal mudflats in the Study Area, composite surface sediment was collected from 15 mudflats to generate a realistic assessment of fish and wildlife exposure to sediment contaminants. This study showed that present concentrations of organic contaminants are elevated throughout the Study Area and are generally higher than concentrations in the reference area and regional waterways. A screening-level analysis showed that there is potential for adverse effects to sediment-associated organisms from a number of chemicals. No spatial trends were apparent for most compounds evaluated, consistent with the presence of multiple sources of chemicals in the Study Area. The exception is semivolatile compounds, which appear to be localized to specific mudflats, indicating potential point-sources of contamination for these chemicals.  相似文献   

6.
Ganga is the largest riverine system of India with a fragile ecosystem. Its prone to anthropogenic disturbances because of its cultural, economic and environmental values. The contamination of river Ganga by heavy metals (HM) is due to biotic (anthropogenic sources) and abiotic (pesticides, fertilizers) sources that poses a devastating health hazard to human, plant and edible fish life. The chemical analysis with the help of atomic absorption spectrometer performed on its water samples demonstrated the accumulation of heavy metals such as Arsenic (As), Lead (Pb), Cadmium (Cd), Iron (Fe), Zinc (Zn). Moreover, the spectrophotometric analysis indicated clearly the accumulation of heavy metals in order of occurrence (Fe > As > Cd > Zn > Pb) in liver and (Zn > Fe > As > Cd > Pb) in kidney of edible fish Channa punctatus. The present study has be used to sensitively monitor the extent of heavy metals pollution in the biotic aqua life of river Ramganga system and its suggested that the bioaccumulation of heavy metal in Channa punctatus has reached above permissible limits for human consumption, indicating potential health risks. Necessary biological steps should be taken to handle such food pollution and prevent the environmental risk and food chain disruption.  相似文献   

7.
In well-controlled experiments using white leghorn chickens and Japanese quail, dietary polychlorinated biphenyls (PCBs), DDT and related compounds produced no detrimental effects on eggshell quality. A drastic reduction in hatchability of chicks occurred with 10-20 ppm PCBs, but no detrimental effects on eggshell quality, egg production or hatchability were found with 0.5 and 1.0 ppm PCBs, or DDT up to 100 ppm. Dietary PCBs potentiated a vitamin E-selenium deficiency in the chick, increased exudative diathesis, and decreased plasma glutathione peroxidase levels. Dietary PCBs induced hepatic microsomal benzopyrine hydroxylase. Dietary levles of 100 or 200 ppm inorganic mercury as HgSO4 or HgCl2 had little effect on egg production, hatchability, shell quality, morbidity and mortality. Methylmercury chloride, however, at levels providing 10 or 20 mg Hg/kg of diet, severely affected all of these parameters. Even though the present experiments demonstrate that neither DDT nor PCBs has any effect on eggshell quality in chickens and Japanese quail, they may cause thinning of eggshells in other species. Controlled experiments are lacking. Eagles, ospreys and pelicans all consume fish which in many areas of the world are known to contain methyl mercury. The thinning of eggshells in the species in the wild may have been due, at least in part, to environmental contamination with methylmercury rather than DDT, DDE or PCBs, as has been claimed.  相似文献   

8.
Sediment quality of North Carolina estuaries was evaluated using synoptic data on sediment chemistry, toxicity, and macroinfaunal community structure from 175 subtidal stations sampled during the summers of 1994–1997. The study area included Currituck, Albemarle, and Pamlico Sounds; estuarine portions of major rivers (e.g., Chowan, Roanoke, Tar-Pamlico, Neuse, New, Cape Fear); and numerous smaller tributaries and coastal embayments between the Virginia and South Carolina borders. A probabilistic sampling design permitted statistical estimation of the spatial extent of degraded versus non-degraded condition across these estuaries. Over half (54 ± 7%) of the surveyed area had high sediment quality characterized by healthy benthic assemblages and low levels of sediment contamination and toxicity. The remaining 46% showed evidence of significant stress in one or more of the above sediment-quality-triad components. While this is a sizable area, portions of it (27 ± 6%) were represented by sites with no connection between presence of stressors and adverse biological responses. Only 19% of the total area showed evidence of an impaired benthos coupled to significant pollution exposure (high sediment contamination, toxicity, or both). Impaired benthic condition was more closely linked to sediment contamination than to low dissolved oxygen (based on instantaneous oxygen measurements). The most pervasive contaminants were the metals arsenic, mercury, chromium, and nickel; the pesticides lindane, dieldrin, DDT, and DDT derivatives; and total PCBs. Degraded condition in all three components of the sediment quality triad co-occurred in <10% of the study area, suggesting that strong contaminant-induced effects on the benthos are limited to a small (yet ecologically significant) percentage of total estuarine area. The spatial extent of sediment contamination and toxicity was much less in these estuaries in comparison to other U.S. coastal regions where similar studies have been performed.  相似文献   

9.
Fingerlings of brown trout ( Salmo trulta m. fario L.) were introduced to sections of different types of streams situated in natural catchments and those modified by Man's activity. At stations where environmental conditions were modified by such forms of impact as pollution, flow variability and impoundment, trout did not survive 5 months. In the natural river sections mortality rates increased downstream along the river continuum and were associated with increased predation. Growth rates in the upper reaches were primarily restricted by abiotic factors—temperature and trophic status: however, they were to a large extent modified by density-dependent regulation and intraspecific competition. The influence of the abiotic/biotic regulatory process, expressed as fish metabolic performance, is discussed as a framework for the determination of the carrying capacity of the riverine ecosystem.  相似文献   

10.
11.
The preparation of sterile parenteral products requires careful control of all ingredients, materials, and processes to ensure the final product has the identity and strength, and meets the quality and purity characteristics that it purports to possess. Contamination affecting these critical properties of parenteral products can occur in many ways and from many sources. The use of closures supplied by manufacturers in a ready-to-use state can be an effective method for reducing the risk of contamination and improving the quality of the drug product. This article will address contamination attributable to elastomeric container closure components and the regulatory requirements associated with container closure systems. Possible contaminants, including microorganisms, endotoxins, and chemicals, along with the methods by which these contaminants can enter the product will be reviewed. Such methods include inappropriate material selection, improper closure preparation processes, compromised container closure integrity, degradation of closures, and leaching of compounds from the closures.  相似文献   

12.
农用化学品污染及预防建议   总被引:1,自引:0,他引:1       下载免费PDF全文
农用化学品是农业生产的重要组成部分,其安全问题也成为人们关注的焦点。农用化学品可分为化肥、农药、农膜3类。化肥主要用于提高土壤肥力,增加农作物产量,不合理使用则会改变土壤性质,降低土壤肥力,并且对生态环境以及人类健康造成不可忽视的危害。农药主要用于杀菌、杀虫、除草等,在促进和保障农作物健康生长中发挥重要作用,但农药的滥用造成农药事故频发,农药的毒性富集作用以及残留问题越发引起人们的关注。农膜主要用于农膜覆盖栽培技术,农膜的原料主要是聚乙烯树脂等高分子化学物质,在土壤中很难降解,造成的环境污染问题日益突出。各种农用化学品的不合理使用,可降低农产品的质量,使其在出口贸易中受到极大限制,造成巨大的经济损失。本文在肯定农用化学品在现代化农业生产中的巨大贡献的同时,深入分析了其污染状况及危害,总结了当前国际上对于化肥、农药、农膜的研究进展以及所取得的成果,最后提出了科学使用农用化学品的建议。  相似文献   

13.
Hormozgan Province plays a vital role in fishery, petroleum, and industrial activities in southern Iran. However, no comprehensive studies on organic pollution have been performed. PCBs and PAHs were analyzed in surface sediments from areas receiving industrial (nine sites), river (one site), and urban (two sites) effluents. The sediment samples were collected in March and September 2010 (in dry and wet seasons) at the highest tidal time. The overall pollution level of PCBs ranged from 2.5 ± 0.8 to 462.0 ± 206.7 ng/g dry weight. CB153 congener dominated in most of the sediment samples. Congener profiles of PCBs showed close similarity with formulations of commercial products such as Aroclor 1260 and 1254 g. A wide range of 55.3 to 1231.6 ng/g dry weight was detected for ∑PAHs. Results of PCA and PCA-MLR tests confirmed both petrogenic and pyrogenic origins for PAH pollution. The higher means of ∑PAHs and ∑PCBs in industrial and urban wastewaters were found near the shore, evidencing the role of these wastewaters in the PAH and PCB contamination in Hormozgan sediment. The concentrations of PAHs and PCBs in detected hotspots exceed the U.S. NOAA sediment quality guidelines.  相似文献   

14.
The River Luzou flows through a sandy substrate in the South West of France. According to the results of two assessment surveys, the Water Agency appraised that this river may not achieve the good ecological status by 2015 as required by the Water Framework Directive (2000/60/EC). This ecosystem is impacted by industrial effluents (organic matter, metals and aromatic compounds). In order to assess and characterize the impact, this study aimed to combine a set of taxonomic and non-taxonomic metrics for diatoms, macrophytes, macroinvertebrates and fish along the up- to downstream gradient of the river. Diversity metrics, biological indices, biological and ecological traits were determined for the four biological quality elements (BQE). Various quantitative metrics (biomass estimates) were also calculated for diatom communities. The results were compared to physicochemical analysis. Biological measurements were more informative than physicochemical analysis, in the context of the study. Biological responses indicated both the contamination of water and its intensity. Diversity metrics and biological indices strongly decreased with pollution for all BQE but diatoms. Convergent trait selection with pollution was observed among BQE: reproduction, colonization strategies, or trophic regime were clearly modified at impaired sites. Taxon size and relation to the substrate diverged among biological compartments. Multiple anthropogenic pollution calls for alternate assessment methods of rivers'' health. Our study exemplifies the fact that, in the case of complex contaminations, biological indicators can be more informative for environmental risk, than a wide screening of contaminants by chemical analysis alone. The combination of diverse biological compartments provided a refined diagnostic about the nature (general mode of action) and intensity of the contamination.  相似文献   

15.
A robust approach to defining, understanding, and tracking contaminant levels is crucial to human and ecological risk evaluation and risk management. Whether materials are present in the environment naturally (mercury, radon, nitrogen, phosphorous) and enhanced by human activities or are man-made (DDT and PCBs), the complexity of contaminant distributions and sources requires careful design and implementation of studies to characterize background. Before collection or analyses of data are initiated, an explicit definition of background appropriate to specific risk assessments is needed. Problems associated with determining background levels of contaminants in fish and seafood illustrate some challenges faced by risk assessors. Major differences in estimates of background may result from differences in sampling and analytical methods including selection of sampling locations, approaches to data analysis and synthesis, and tissues selected for analysis. Different approaches may yield background exposure or risk estimates that differ by 50% or more. Methodological transparency is essential in data collection and analysis to establish background and to ensure that data are used appropriately in both human and ecological risk assessments.  相似文献   

16.
Virus-associated mass mortalities among several marine mammal populations inhabiting industrialized coastal areas have generated an interest in wildlife immunotoxicology. Despite the isolation of previously uncharacterized viruses from victims, a contribution of immunotoxic contaminants to the severity of the outbreaks could not be ruled out. Fish-eating marine mammals, including seals, occupy high trophic levels in the aquatic food chain, and accumulate high levels of contaminants including polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychorinated dibenzofurans (PCDFs). Such chemicals have been found to be immunotoxic at low doses in studies of laboratory animals. While associations have been established between environmental contaminants and various adverse biological effects in certain free-ranging seal populations, evidence for immunotoxicity has, until recently, been lacking. To this end, we carried out an immunotoxicological study, in which captive harbor seals were fed herring from either relatively uncontaminated sites of the Atlantic Ocean, or from the highly contaminated Baltic Sea. In this review, we summarize the contaminant-related immunosuppression observed in the captive group of seals fed herring from the Baltic Sea, and discuss these results in the context of what is currently known about outbreaks of virus infection, comparative immunology, and environmental contaminants. We also describe two parallel studies, in which laboratory rats exposed as adults or perinatally to the contaminants in the Baltic Sea herring, exhibited immunotoxicity. On the basis of these and other studies, we conclude that complex mixtures of environmental contaminants may represent a real immunotoxic risk to free-ranging marine mammals in many areas of Europe and North America.  相似文献   

17.
This paper presents the findings of a study on adsorption of dichlorodiphenythreechloroethen (DDT) and polychlorinated biphenyls (PCBs) on three nanomaterials including Multi walled Carbon Nanotube (MWNT), nano-clay and nano-alumina. DDT and PCBs are of significant concern due their high toxicity and long environmental half-lives. Experiments were conducted using batch adsorption procedures at different DDT and PCBs concentrations, from 10 to 60 mg/L. The amounts of MWNT, nano-clay and Nano-alumina used were 0.25%, 0.50%, 0.75%, 1%, 2% and 10%. The adsorption of PCBs solution onto the MWNT, nano-clay and nano-alumina was characterized by an initial rapid adsorption which eventually became constant within 22, 20, and 17 hours, respectively. The adsorption of DDT solution onto the MWNT, nano-clay and nano-alumina was also characterized by an initial rapid adsorption which gradually became constant within 22, 22 and 16 hours, respectively. Results of this study indicated that MWNT was a better adsorbent material compared to nano-clay and nano-alumina for both contaminants in this study. While at 10% of MWNT 88.9% and 77% of DDT and PCB were removed by MWNT, respectively. The effect of pH and temperature were also investigated.  相似文献   

18.
The Hadera River is the most polluted among the Mediterranean coastal rivers of Israel due to abundant E. coli, high concentrations of heavy metals and nutrients, and high temperatures. In 2003–2008 we found 191 species of algae and cyanobacteria belonging to seven taxonomic divisions. The upper reaches were dominated by cyanobacteria and exhibited levels of toxic pollution. Downstream, the ecological niches of algal communities dramatically changed: upper stream diversity first increased and then decreased due to the influx of rainwater in the tidal zone during winter. On one hand, seasonal dynamics show that in winter, inorganic contamination was reduced because of dilution by the influx of rainwater, but, on the other hand, organic pollution increased from agriculture. Down the river, diversity increases and the community composition undergoes considerable change. In summer, algal blooms indicate a reduction of stress and aid in the river’s self-purification. The WESI indices and RPI show steady year-round stressful conditions for algal photosynthesis with increasing instability in the river. Perpetuation of the current situation would disturb the self-purification capacity of the river ecosystem through destruction of biotic components. Statistical analysis (CCA) reveals the impact of wastewater as the most important stress factor for the Hadera River ecosystem, which is an exceptionally strong example of self-purification.  相似文献   

19.
Soils contaminated with hydrocarbons and others contaminants (heavy metals, PCBs, PAHs) were recently discovered in the banks of the Saint-François and Massawippi rivers. The aim of this study is to attempt to date the contamination events using dendrochronological and dendrochemical methods. For this study, dendrochronology is used to indicate the age of trees, identify the morphological growth anomalies, and provide the geochemical profile timeframe, with dendrochemistry used specifically to identify metal element concentrations in the growth rings of the selected specimens. Sampling for the two types of analysis was done on the banks of the Saint-François River in Windsor and Richmond, where the level of hydrocarbon contamination in the soil profiles is among the highest. Core samples were taken from three red ash (Fraxinus pennsylvanica Marsh.) and dendrochemical analyses were done on the tree rings (191 samples). Dendrochemistry was successfully used to determine that there were heavy metals in the rings, and also to estimate the date of the contamination events by using tree-ring wood. Several contamination events were identified through the presence of lead and other metal trace elements (As, Cd, Cu, Ni, and Zn) in the xylem of the trees analyzed at the selected sites. This suggests that various contaminants were transported by the river on several occasions and deposited on floodplains during successive floods. The atmospheric fallout must also be considered as the other source of pollutants recorded in the trees.  相似文献   

20.
Ecotoxicology and environmental epidemiology require an intimate understanding of the relationship between exposure of a population to a pollutant and the subsequent biological effects. This article summarizes two relatively new and powerful techniques to examine both exposure and response to environmental pollutants which build upon an increased understanding of how particular classes of chemicals elicit toxicity at the molecular level. The genetic reporter assay can be used to examine the exposure and potential toxicity of environmental samples. Quantitative polymerase chain reaction (PCR) is an exquisitely sensitive and adaptable procedure to examine early events, i.e. biomarkers, that might be indicative of exposure and/or sensitivity to a chemical insult. Taken together, these assays are important new tools in assessing the exposure and risk of human and wildlife populations to such important pollutants as dioxins, PCBs, oestrogenic and anti-oestrogenic compounds, phthalate esters, DDT metabolites and heavy metals.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号