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1.
Organochlorines and organophosphates were measured in four fish species (Lateolabrax japonicus, Pagrasomus major, Miichthys miiuy and Epinephalus awoara) and the mussel Perna viridis collected from aquaculture cages in coastal waters of Xiamen, China. Polycyclic aromatic hydrocarbon (PAH) metabolites were also measured in fish bile. Sites in Xiamen coastal waters (the harbour, Maluan and Tongan) are compared with a "cleaner" reference site at Dongshan Island. DDT was found in livers of all fish sampled (May 1998, 1999 and December 1999) ranging from 0.15 to 2.2 microg/g WW, but levels in muscle tissue (<0.5 ng/g to 0.22 microg/g WW) were at least an order of magnitude lower in the harbour, and were not detectable (<0.5 ng/g) in Tongan samples. All other pesticides examined were not detected in fish or mussels, except for dieldrin in one liver sample (0.07 microg/g WW). Food of the caged fish, small fish and dried pellets, had very low (0.015-0.027 microg/g WW) or non-detectable levels of DDT, indicating significant bioaccumulation of contaminants in caged fish and/or other possible sources of uptake (water and sediments). DDT levels in fish varied with species. DDT contamination in fish livers and whole mussels varied significantly with location. Highest concentrations in fish occurred in the harbour, and less consistently so in Tongan. Dongshan and Maluan had comparatively low levels of DDT. Relatively low residues of DDT in both fish and mussels at Dongshan likely reflect lower levels of pesticide input at this reference site. However, the low levels of DDT contamination in fish tissues from Maluan were unexpected in view of the close proximity of the harbour and possibly reflect the removal of particulate-bound contaminants by the intensive bivalve culture there. Consistently high proportions of DDT in the form of the parent compound (p,p'-DDT: fish 30-45%; mussels 40-65%) from all sites suggest recent releases of this chemical to the environment. Levels of two main groups of PAH metabolites (naphthalene and phenanthrene) in fish bile suggest a different environmental distribution pattern than that of pesticides, in that Dongshan fish appear to be no less exposed to hydrocarbons than those from Xiamen coastal waters.  相似文献   

2.
Coastal contamination in the 1940s was assessed based on analysis of canned blue mussels presumably collected from Birch Harbor, Maine, USA. Analytical results on legacy organic contaminants were compared to long-term National Oceanic and Atmospheric Administration (NOAA) Mussel Watch (MW) monitoring data to estimate the degree of coastal contamination before World War II (WWII) when many synthetic organic compounds were first introduced into the environment. While dieldrin and chlordane were not detected in the canned mussels, dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexanes (HCHs) were present at lower concentrations relative to the more recent MW data. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were detected, and the later were significantly higher in canned mussels relative to the MW data (p < 0.05). Furthermore, moving average analysis applied to the MW data depicted three-phased temporal trend patterns (increase-decrease-steady state) for virtually all contaminants indicating an overall increased coastal contamination in post WWII era.  相似文献   

3.
The Sørfjord (Western Norway) has a long history of industry and pollution, and has been monitored for several decades. The environmental monitoring has comprised analyses of different contaminants in sea water, mussel, fish, seaweed and sediments. Measurements of polychlorinated biphenyls (PCBs) in blue mussels (Mytilus edulis) some 17 years ago indicated a local source. In 2001 severe concentrations were measured in blue mussels and further investigations disclosed the primary source of PCBs in the Sørfjord. In 2002, extreme PCB-concentrations were found in cod (Gadus morhua) from the same area. However, no induction of EROD activity was detected, indicating the limitations of this assay as marker for PCB contamination. A future scientific challenge will be to understand the specific mechanisms and effects of such PCB accumulation in fish.  相似文献   

4.
The paper presents the results of monitoring trace organic contaminants (17 PCBs and 7 OCPs) and 6 trace metals (Cd, Cr, Cu, Hg, Pb and Zn) in the coastal waters of the eastern Adriatic in 2006 using Mytilus galloprovincialis as indicator species. OCPs were found in all samples (0.07-14.3 ng g−1 d.wt.), while in positive samples concentrations of PCBs ranged between 0.16 and 20.5 ng g−1 d.wt. The α-HCH/γ-HCH and DDE/DDT ratios indicated recent input of γ-HCH and DDT. Spatial distributions of HCB, PCBs, DDTs and Hg were significantly correlated with population density. Although elevated concentrations of all trace metals and organic contaminants were recorded in the densely populated and industrialized areas, overall data point to relatively low level of contamination of the eastern Adriatic coast. Evaluation of the risks to human health associated with consumption of the mussels suggested that there is no health risk for moderate shellfish consumers.  相似文献   

5.
Residues of DDT isomers accumulated in the testes of Channa punctatus (BLOCH) were quantitatively estimated by exposing the fish to 2.5 ppm sublethal concentration for 32 days. The study revealed a high accumulation of DDT residues in the testes. The maximum concentration of residues was noted on the 32nd day of the experiment. The DDT isomer accumulated in maximum concentrations was followed by DDE and DDD isomers. The maximum residue concentrations were 0.3221 ppm (DDT), 0.1119 ppm (DDE) and 0.0695 ppm (DDD) on the 32nd day of the experiment. The total DDT residue concentration at the final interval was 0.563 ppm.  相似文献   

6.
A steady-state nonequilibrium fugacity model incorporating the oceanographic dimensions of the environment receiving a sewage discharge from Sydney, Australia was used to predict the environmental fate of a range of chlorohydrocarbon contaminants. The model showed advection in water to be the dominant removal process, accounting for all except 1–2% of the contaminants discharged. With the exception of the more water soluble dieldrin, the major portion of contaminant present in the area was held in the sediments. Bioconcentration and sediment sorption models were used with levels detected in the biota and sediments to calculate the ambient water concentrations of the chlorohydrocarbon contaminants. The ambient water concentrations calculated using these models were in general agreement within a factor of about 2 in all but one case, and that was in agreement within an order of magnitude. The fugacity model was also used to estimate the rates of discharge of each of the contaminants. These were chlordane 83–640, DDT 150, dieldrin 1400–1500, hexachlorobenzene 360–400 and PCBs 55–96 g day−1. Comparisons of the calculated ambient concentrations of each compound in the water and in fish in waters adjacent to the discharge point before and after its relocation from a cliff-face to a deepwater site indicated that relocation should result in an order of magnitude reduction.  相似文献   

7.
Trace organic (chlorinated pesticides, PCBs, PAHs and dioxins/furans) and trace metal concentrations were measured in surficial sediment and biological tissues (i.e., worms, crustaceans, bivalve molluscs, and fish livers) collected from the Russian Arctic. Total DDT, chlordane, PCB and PAH concentrations ranged from ND to 1.2, ND to <0.1, ND to 1.5 and <20-810 ng g(-1), respectively, in a suite of 40 surficial sediment samples from the Kara Sea and the adjacent Ob and Yenisey Rivers. High sedimentary concentrations of contaminants were found in the lower part of the Yenisey River below the salt wedge. Total dioxins/furans were analysed in a subset of 20 sediment samples and ranged from 1.4 to 410 pg g(-1). The highest trace organic contaminant concentrations were found in organisms, particularly fish livers. Concentrations as high as 89 ng g(-1) chlordane; 1010 ng g(-1) total DDTs; 460 ng g(-1) total PCBs; and 1110 ng g(-1) total PAH, were detected. A subset of 11 tissue samples was analysed for dioxins and furans with total concentrations ranging from 12 to 61 pg g(-1). Concentrations of many trace organic and metal contaminants in the Kara Sea appear to originate from riverine sources and atmospheric transport from more temperate areas. Most organic contaminant concentrations in sediments were low; however, contaminants are being concentrated in organisms and may pose a health hazard for inhabitants of coastal villages.  相似文献   

8.
Cellular changes in livers from flounder (Platichthys flesus L.) and digestive glands of blue mussels (Mytilus edulis) were studied to analyze whether the Elbe flood catastrophe in August 2002 had any deleterious effects on animal health. Flatfish and mussels were sampled at different locations in the Elbe estuary and the Wadden Sea after the flood wave had reached the German Bight. Internationally used core biomarkers (lysosomal membrane stability, biotransformation enzymes) were applied to assess the toxic effects of putatively increased pollution levels. In comparison to earlier data from long-term studies at the same stations, we found a significant impairment in the function of cell organelles (lysosomes) involved in the detoxification and elimination of pollutants in fish liver. Concentrations of relevant contaminants (organochlorines, polychlorinated biphenyls) were analyzed in parallel with cellular biomarkers, and conspicuously raised concentrations of insecticides metabolites were detected. Cell recovery and a clear reduction in contaminant concentrations were observed in fish livers five months after the flood at all sampling sites except the Helgolander Tiefe Rinne.  相似文献   

9.
Mussel Watch techniques were used to measure the concentrations of petroleum hydrocarbons, synthetic organic hydrocarbons, and trace metals in a preliminary study of the Monterey Bay area in central California. Resident mussels were found to have higher-than-expected petroleum hydrocarbon body burdens in Carmel Bay, an area thought to be relatively contaminant free. A ‘hot spot’ of PCB 1254 and pp′DDE was measured at Año Nueuvo Island, a site previously recognized because of elevated levels of mercury in mussels. PCB 1254 concentrations at Año Nuevo Island were high in relation to the remainder of coastal United States and Baja California, reflecting entrainment of this compound at a biologically active area. The Monterey Harbor Jetty location showed the highest contamination levels for zinc and lead. In fact, this location has the second highest lead concentrations in mussels for the California coast. Biological cycling of certain compounds (PCB, DDT and mercury) in remote locations such as Año Nuevo Island, is hypothesized as a mechanism for these elevated concentrations in mussels. Levels of other synthetic organic hydrocarbons were generally low, with chlordanes showing higher concentrations in the more urbanized locations of the study area, i.e. the Monterey Harbor Jetty.  相似文献   

10.
The concentration of synthetic chlorinated hydrocarbons has been monitored in mussels collected on the north-west Mediterranean coast. DDT and PCB contamination is widespread in this region and the results suggest that the mussels are directly exposed to DDT. Seasonal changes in fat content of the mussels and the (unknown) rates of chlorinated hydrocarbon accumulation and excretion make the detailed interpretation of data difficult and limit the value of mussels as bio-indicators of pollution.  相似文献   

11.
放养河蚌,提高水体透明度以促进沉水植物生长,是湖泊生态修复中的常用手段之一.而小型杂食性鱼类鳑鲏依赖河蚌繁殖,河蚌放养可能会促进鳑鲏种群的发展;而鳑鲏与河蚌交互作用对水生态系统的影响仍研究较少.于2018年11 12月通过原位受控实验,设置对照组、河蚌组、鳑鲏组和河蚌+鳑鲏组,研究了鳑鲏(大鳍鱊Acheilognathus macropterus)与河蚌(背角无齿蚌Sinanodonta woodiana)对水质、浮游生物和底栖生物的影响.结果表明:鳑鲏显著增加了上覆水总氮、总磷、悬浮质和叶绿素a(Chl.a)浓度;但并未显著影响无机悬浮质的浓度,说明鳑鲏对沉积物的扰动作用较弱.此外,鳑鲏显著增加了浮游植物生物量和蓝藻的比例.浮游动物总生物量并未受鳑鲏的影响,但显著增加了浮游动物的丰度,其中以轮虫为主.鳑鲏组的底栖动物总丰度(主要为水丝蚓)显著高于对照组,说明鳑鲏对水丝蚓的摄食压力较低.鳑鲏与河蚌交互作用对总磷、Chl.a、浮游植物和浮游动物丰度具有显著影响:具体表现为河蚌虽然抵消了部分鳑鲏对水质(如氮、磷和悬浮质浓度,以及Chl.a浓度和浮游植物生物量等)的负面影响,但其对浮游动物和水丝蚓生物量的影响不显著.在湖泊生态修复和管理中,需要关注和重视鳑鲏等此类小型杂食性鱼类对水生态系统可能产生的负面影响,通过物理(网簖等)或生物(放养肉食性鱼类)等方式将其控制在较低密度水平,从而降低这些鱼类对水质、浮游生物和底栖生物群落可能产生的负面影响,维持生态修复效果的长效与稳定运行.  相似文献   

12.
The bioaccumulation of PCB and DDT compounds by mussels, Mytilus spp., from ambient seawater was determined by measuring concentrations of these chlorinated hydrocarbons in both mussels and seawater at four sites on the Mediterranean coast of France and two sites in California. Bioaccumulation factors were found to vary over an order of magnitude. Ratios of the concentrations of PCB in mussels, consisting predominantly of pentachloro-and hexachlorobiphenyls, to concentrations in ambient seawater ranged between 69 000 and 690 000; the corresponding ratios of concentrations of p,p′-DDE or p,p′-DDT ranged from 40 000 to 690 000. Although mussels appear to be appropriate and convenient indicator organisms of local chlorinated hydrocarbon contamination levels, the factors contributing to this variance must be determined before mussels are widely used in global monitoring programmes.  相似文献   

13.
The presence of organochlorine pesticides and polychlorinated biphenyls in wild and farmed gilthead sea bream (Sparus aurata) from the Western Mediterranean, Spain, is investigated. These pollutants were determined in white and red muscle and liver by gas chromatography coupled to tandem mass spectrometry. Contaminant profiles present in both wild and farmed fish tissues include DDTs, PCBs and HCB. The highest concentrations of contaminants were found in liver, and an increase in pollutant levels was observed in autumn, before spawning. This fact is explained in light of increased food intake when sea water temperatures increase. Gilthead sea bream from Western Mediterranean populations showed significantly higher concentrations of DDTs and PCBs than farmed fish from the same area. This fact is attributed to the low level of organochlorine contaminants present in fish feed supplied to the cultured fish. The diet is highlighted as an important factor in understanding differences observed in organochlorine pollutants levels of fish tissues.  相似文献   

14.
The marine environment continues to be adversely affected by tributyltin (TBT) release from maritime traffic. Therefore the concentrations of TBT, dibutyltin (DBT) and monobutyltin (MBT) were measured in barnacles, mussels and fish along the Eastern Aegean coastline. The average concentrations of TBT ng Sn g−1 were found to be 235 in fish, 116 in mussels and 635 in barnacles. The highest concentrations of TBT, DBT and MBT were observed in the barnacles which had been sampled in marinas and harbors. All mussels sampled showed values of TBT + DBT, which were below the “tolerable average residue level (TARL)” as currently accepted. This indicates a lack of risk to the consumer. However, 7 out of the 15 fish sampled displayed TBT + DBT levels above the TARL, which indicates that a fish consumer group may be at risk. Barnacles have high potential as biomonitors for the presence of organotin in the Aegean Sea.  相似文献   

15.
The concentration ranges of chlorinated hydrocarbons in marine fish were HCB (0.03–9.5 ppb), Lindane (0.02–5.3 ppb), Endosulphan (0.21–4.9 ppb), DDT (0.50–18.6 ppb), Aldrin (0.05–54.6 ppb) and PCB (4.78–225 ppb). Fish contained higher concentrations of Aldrin, Heptachlor, HCB and Lindane than shellfish, while a reverse trend was observed for DDT and PCBs. The concentrations of residues obtained were found to be lower than those reported in literature for industrialized countries. Predator fish species were found to concentrate more residues in muscle tissue than plankton feeders. The DDT/PCB values were less than 1 indicating a predominance of industrial activities over agricultural activities as the source of contamination of the marine environment. The fish Galeoides decadactylus is a potential bio-indicator for chlorinated hydrocarbons pollution monitoring in the study area.  相似文献   

16.
重建沉水植物群落是修复浅水富营养化湖泊的关键.河蚌可改善水下光照条件、促进沉水植物生长,因此放养河蚌常被用于沉水植物群落恢复的并行手段.河蚌是鳑鲏产卵的重要基质,因此河蚌可能促进鳑鲏种群发展,而鳑鲏对水生态系统的影响还尚不清楚.本研究以密刺苦草、大鳍鱊和背角无齿蚌为研究对象,通过中宇宙试验研究河蚌和鳑鲏对附着藻的影响,以及鳑鲏对水质和沉水植物生长的影响及机理.结果发现:鳑鲏显著增加了水体总磷、总溶解性磷、总悬浮物和叶绿素a浓度,而对总氮和总溶解性氮浓度的影响不显著.河蚌对苦草的相对生长率、总株数、根冠比及苦草最大叶长均无显著影响,而显著增加了苦草的单株平均生物量,这可能与河蚌组较高的附着藻生物量有关.鳑鲏未显著影响河蚌与苦草间的关系,但鳑鲏的出现显著增加了附着藻类生物量;此外,鳑鲏还降低了苦草的根冠比,而增加了苦草的最大叶长,这可能与鳑鲏引起的营养盐和叶绿素a浓度升高,以及植物表面附着藻生物量显著升高有关.鳑鲏属于小型杂食性鱼类,在长江中下游地区分布广泛,与沉水植物关系密切,且易在修复后的湖泊中形成优势鱼类,因此在湖泊修复和管理中应加强此类小型杂食性鱼类的监测与管理.  相似文献   

17.
Investigations were made of 212 fish samples of eight fish species from 29 lakes of the Schwerin county. Determinations were made gas-chromatographically after chemical derivatization. In lakes with a low anthropogenic load the following concentrations were found: 0.05 mg/kg DDT, 0.03 mg/kg PCB. In lakes with higher pollution, the concentrations were 0.21 mg/kg DDT and 0.42 mg/kg PCB. The limit of tolerance for foodstuffs was never exceeded and predatory fish did not show higher concentrations than non-predacious fish. For ten eels, however, the mean contents were 1.6 mg/kg DDT and 0.36 mg/kg PCB. The total content of DDT in all fishes was composed as follows: 70 … 75% p,p′-DDE, 15 … 20% p,p′-DDD and 5 … 10% p,p′-DDT. Trout from an intensive-breeding plant contained 0.16 mg/kg DDT and 0.04 mg/kg PCB from the contaminated feed. By means of a change-over to different feed the contents were reduced to 0.03 mg/kg DDT and 0.04 mg/kg PCB.  相似文献   

18.
The endangered Western population of the Steller sea lion declined for three decades for uncertain reasons. We present baseline data of metal concentrations in pups as a first step towards investigating the potential threat of developmental exposures to contaminants. Seven metals were investigated: arsenic, cadmium, silver, aluminum, mercury, lead and vanadium. Vanadium was detected in only a single blubber sample. Mercury appears to be the most toxicologically significant metal with concentrations in the liver well above the current action level for mercury in fish. The concentrations of aluminum, arsenic, silver, cadmium and lead were present in one-fourth to two-thirds of all samples and were at either comparable or below concentrations previously reported. Neither gender nor region had a significant effect on metal burdens. Future work should consider metal concentrations in juveniles and adults and toxicological studies need to be performed to begin to assess the toxicity of these metals.  相似文献   

19.
Due to their close proximity to the point sources of pollution, estuaries and harbours are exposed to metals. Mussels are used worldwide to monitor marine pollution due to their ability to take up contaminants and the ease of transplantation. Mussels were collected from two reference sites and transplanted in Richards Bay Harbour (2006 and 2010) and in three harbours. Transplanted and resident mussels were removed after 6 weeks exposure and metal concentrations were analysed using ICP-MS techniques. Transplanted mussels had higher metal concentrations than the resident mussels. This was attributed to regulation of metals by the resident mussels. Metal regulation was greater in mussels that are continuously submerged as opposed to those that undergo tidal influences. For monitoring it is essential that the reference population for transplantation is considered carefully as upwelling events in the pristine reference location results in significant increases in metal bioaccumulation.  相似文献   

20.
A collaborative sampling cruise off the central California coast was conducted to evaluate contaminant transport pathways along and across the shelf in the spring of 2002. The area has a complex current structure and net transport routes are not known for sure. Sediment characteristics, and organic and trace metal contaminants were analyzed in sediments taken from locations near shore, out to the heads of several canyons. Relative to the continental shelf and Pioneer Canyon stations, DDT was found at higher concentrations in Ascension and Monterey Canyons. Monterey Bay still receives DDT from terrestrial runoff and may be the source of DDT found in Ascension Canyon. DDT concentrations in Monterey Bay biota indicate bioaccumulation is occurring at depth due to continuing input from the shore. Effects on the deep ocean benthic community is unknown.  相似文献   

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