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1.
This paper presents the results of a study on changes in 137Cs activity concentrations in three fish species from the southern Baltic Sea: cod (Gadus morhua), herring (Clupea harengus) and flounder (Platichtys flesus), in the period 2000–2010. During the study period a marked decline in cesium activity concentration in fish muscle tissue was observed, which reflected changes in radionuclide activity concentration in seawater. No statistically significant temporal trends were determined in changes of concentration factors (CFfish/seawater) calculated for the examined fish species. The analysis of 137Cs activity as a function of ichthyological parameters revealed the lack of a relationship between radionuclide activity concentrations in herring muscle tissue and the fish age in an narrow age range (2–4 years). However, a reverse proportionality of total fish mass, as well as body length, against 137Cs activity concentrations in muscles was well documented. The latter observation can be the direct result of the dilution effect related to the increase of fish body weight. 137Cs activity concentration in muscle tissue of the five fish species forms a declining sequence: Gadus morhua, Platichthys flesus, Clupea harengus, Perca fluviatilis and Neogobius melanostomus.  相似文献   

2.
The results of seven years lysimeter experiments to determine the uptake of 60Co, 137Cs and 226Ra into agricultural crops (endive, maize, wheat, mustard, sugarbeet, potato, Faba bean, rye grass) are described. The lysimeter consists of twelve monolithic soil profiles (four soil types and three replicates) and is located in Seibersdorf/Austria, a region with a pannonian climate (pronounced differences between hot and semi-arid summers and humid winter conditions, annual mean of precipitation: 517 mm, mean annual temperature: 9.8 degrees C). Besides soil-to-plant transfer factors (TF), fluxes were calculated taking into account biomass production and growth time. Total median values of TF's (dry matter basis) for the three radionuclides decreased from 226Ra (0.068 kg kg(-1)) to 137Cs (0.043 kg kg(-1)) and 60Co (0.018 kg kg(-1)); flux values exhibited the same ranking. The varying physical and chemical properties of the four experimental soils resulted in statistically significant differences in transfer factors or fluxes between the investigated soils for 137Cs and 226Ra, but not for 60Co. Differences in transfer between plant species and plant parts are distinct, with graminaceous species showing, on average, TF values 5.8 and 15 times lower than dicotyledonous species for 137Cs and 60Co, respectively. This pattern was not found for 226Ra. It can be concluded that 137Cs transfer is heavily influenced by soil characteristics, whilst the plant-specific factors are the main source of TF variability for 60Co. The variability of 226Ra transfer originates both from soil properties and plant species behaviour.  相似文献   

3.
Recent detection of fluoxetine in the aquatic environment and fish suggests a possibly high accumulation of fluoxetine; however, no report is available on the bioaccumulation of fluoxetine in aquatic organisms. Since bioaccumulation of fluoxetine was probably dependent on pH near the pK(a) value of 10.1, experiments were conducted approximately at pH 7, 8, and 9. Distribution coefficients between 1-octanol and water (D(ow)), and those between synthetic membrane vesicles (liposomes) and water (D(lip-wat)) were determined at pH 7, 8, and 9. The D(ow) and D(lip-wat) values increased significantly with increasing pH. Acute toxicity tests were performed using Japanese medaka (Oryzias latipes) prior to the bioaccumulation test, and 96-h LC(50) values were 5.5, 1.3, and 0.20mgl(-1) at pH 7, 8, and 9, respectively. In the bioaccumulation test, concentrations of fluoxetine and its major metabolite, norfluoxetine, in the fish body and liver were measured. The bioconcentration factors (BCF) of fluoxetine for Japanese medaka were 8.8, 3.0x10, and 2.6x10(2) in the body and 3.3x10(2), 5.8x10(2), and 3.1x10(3) in the liver at pH 7, 8, and 9, respectively. The BCF values were lower at pH 7 and higher at pH 9 mainly because of the increase in nonionized species with significantly higher hydrophobicity than the ionized species at pH values closer to pK(a). A similar trend was obtained for the concentration of norfluoxetine in the fish but the pseudo-BCF values (the ratio of the norfluoxetine concentration in the fish and the fluoxetine concentration in test water) were higher than the BCF value of fluoxetine at all pH conditions.  相似文献   

4.
Dissipation study of sulfosulfuron in natural water and its bioaccumulation in fish was conducted at 25+/-2 degrees C and at two different concentration levels 1mgl(-1) and 2mgl(-1). The dissipation data in water showed the DT50 and DT90 values 67-76 and 222-253 days and followed first order kinetics. Bioaccumulation of sulfosulfuron in fish was conducted under static conditions exposing the fish at one-tenth of sub-lethal concentration 9mgl(-1) and at double the concentration 18mgl(-1), for a period of 56 days. On different occasions fish samples were collected and analyzed. A HPLC-RF method was used for the quantification of sulfosulfuron and aminopyrimidine with the limit of quantification 0.001microg ml(-1). Results showed the accumulation of residues of sulfosulfuron in fish over the concentration range 0.009-0.496microg g(-1). Both in water and fish samples, identified the presence of metabolites aminopyrimidine, desmethyl sulfosulfuron, guanidine, sulfonamide, ethyl sulfone and rearranged amine. The formations of these metabolites are confirmed by LC-MS/MS analysis. An LC-MS/MS electro spray ionization technique was used for this purpose. One of the metabolite Aminopyrimidine was identified at higher concentration levels (0.01-0.1microg ml(-1)) when compared with other metabolites. Subsequently dissipation of aminopyrimidine in water and its bioaccumulation was also studied at the concentration level 1mgl(-1) and 2mgl(-1). The calculated DT50 and DT90 values are 66-68 days and 218-226 days, respectively. This followed first order kinetics. Three hundred days after the exposure complete demineralization was observed.  相似文献   

5.
Samples of pond sediment, fish, and shrimp were collected from the Ramsar site at Mai Po marshes, Hong Kong (south China), and samples of pond sediment, fish, and shrimp, as well as eggs of water birds (Chinese Pond Herons (Ardeola bacchus) and Little Egrets (Egretta garzetta)), were collected from two smaller wetland sites at Jiangsu Province (mid-China), between 2004 and 2007. Accumulation levels of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in the biota were used to calculate biota–sediment accumulation factor (BSAF) and bioaccumulation factor (BAF). For fish and shrimp, BSAFs of OCPs (3.8–56) were greater than those of PAHs (0.12–6.3). BSAFs and BAFs of 11–79 and 4–34, respectively, were registered for OCPs in eggs of the birds and were greater than those for PAHs (0.11–1.5 and 0.02–1.3, respectively). Assuming that fish were the main prey of the birds, greater bioaccumulation of OCPs was detected for both bird species (BAFs?=?4.5–34), while accumulation of PAHs was only detected in Little Egret (BAF?=?1.3). A significant linear relationship (p?<?0.01) was observed between concentrations of OCPs in bird eggs and in the prey fish. The present study provides a new possibility of using OCP levels detected in prey fish to predict the extent of OCPs contamination in eggs of waterbirds including the endangered species, as a noninvasive method.  相似文献   

6.
The Baltic Sea is a species-poor, semi-enclosed, brackish sea, whose sediments contain a wide range of contaminants, including sediment-associated metals and radionuclides. In this study, we have examined and compared bioaccumulation kinetics and assimilation efficiencies of sediment-associated (51)Cr, (63)Ni and (14)C in three key benthic invertebrates (the deposit-feeding Monoporeia affinis, the facultative deposit-feeding Macoma baltica, and the omnivorous Halicryptus spinulosus). Our results demonstrate that (i) all radionuclides were accumulated, (ii) the different radionuclides were accumulated to various extents, (iii) small changes in organic carbon concentration can influence the accumulation, and (iv) the degree of accumulation differed only slightly between species. These processes, together with sediment resuspension and bioturbation, may remobilise trace metals from the sediment to the water and to higher trophic levels, and therefore should be taken into account in exposure models and ERAs.  相似文献   

7.
Mushrooms and soils collected from pine forests in Izmir, Turkey were measured for radiocesium and stable Cs in 2002. The ranges of (137)Cs and stable Cs concentrations in mushrooms were 9.84+/-1.67 to 401+/-3.85Bqkg(-1) dry weight and 0.040+/-0.004 to 11.3+/-1.09mgkg(-1) dry weight, respectively. The concentrations of (137)Cs and stable Cs in soils were 0.29+/-0.18 to 161+/-1.12Bqkg(-1) dry weight and 0.14+/-0.004 to 1.44+/-0.045mgkg(-1) dry weight, respectively. Even though different species were included, the concentration ratios of (137)Cs to stable Cs were fairly constant for samples collected at the same forest site, and were in the same order of magnitude as the (137)Cs to stable Cs ratios for the organic soil layers. The soil-to-mushroom transfer factors of (137)Cs and stable Cs were in the range of 0.19-3.15 and 0.17-12.3, respectively. The transfer factors of (137)Cs were significantly correlated to those of stable Cs.  相似文献   

8.
IAA effect on responses of West African algae Caloglosa, Bostrychia, Rhizoclonium and the fresh water alga Pithophora to different growth conditions was examined in growth chamber experiments. The auxin (2.28 x 10(-5) M) caused growth increase of 2.3- and 2.6-fold in Caloglossa and 1.6 and 1.7 in Rhizoclonium, respectively, in sea water and 1:1 diluted sea water/Erdschreiber medium. In Bostrychia pronounced deterioration of growth was noticed in the control samples between 16 and 32 days in culture. The cultures maintained an active growth, however, in the presence of IAA. IAA also allowed Pithophora to withstand salinity: Compared to growth in fresh water, a 65% growth inhibition was recorded in 1:1 diluted sea water in the absence of auxin and a slight growth stimulation when the auxin was present. Pithophora and Rhizoclonium also maintained higher rates of growth in extremal temperatures of 10 and 45 degrees C when the auxin was present.  相似文献   

9.
Following the Chernobyl accident in late April 1986, central Finland was subjected to considerable radioactive fallout. The radioactive isotope of caesium, (137)Cs, was potentially the most harmful isotope in the fallout because of its long half-life (30 years). (137)Cs activities remained unexpectedly low within the biota (algae, zooplankton, aquatic moss, fish) of some humic forest lakes in southern Finland compared to the clear water lakes within the same district. This observation suggested that humic substances, by binding (137)Cs chemically, may reduce its bioavailability in lake water. Our laboratory experiments (throughflow systems; gel chromatography) demonstrated that binding of (137)Cs by humic substances was negligible in untreated lake waters; only when most of the alkali metals had been removed with an ion exchange resin was any binding of (137)Cs by low molecular humic fractions apparent. Instead, the concentrations of cations (especially potassium) were of overwhelming importance for the bioavailability of (137)Cs within the lacustrine ecosystems. The concentrations of (137)Cs within food chains are expected to stay at a high level for many years especially in lakes with long water renewal times.  相似文献   

10.
Laboratory analyses of 137Cs uptake by sunflower, reed and poplar   总被引:2,自引:0,他引:2  
Soudek P  Tykva R  Vanek T 《Chemosphere》2004,55(7):1081-1087
The 137Cs uptake by three plant species (Phragmites australis L., Heliantus annus L., Populus simonii L.) was analyzed in a hydroponic medium (14 MBql(-1); 0.5 mM CsCl) during cultivation. The radioactivity disappearance from the medium was measured after 2, 4, 8, 16 and 32 days of cultivation. Radioactivity distribution within the plant was determined by autoradiography. We did not find differences between uptake of radioactive and stable caesium isotopes. Relations between the uptake of 137Cs and concentration of potassium and ammonium ions in medium were also tested. The highest uptake of radiocaesium by sunflower was obtained for medium with 1 mM K2SO4 (14.2%) and in case of ammonium ions for concentration ratio 6 mM NH4Cl : 3 mM NH4NO3 (13.2%). The obtained results make it possible to compare the capability and rate of 137Cs phytoremediation of different plant species.  相似文献   

11.
Several cesium and strontium bioaccumulation models are used widely in national and international guidance for ecological and human health risk assessments for radiocesium (134Cs and 137Cs) and radiostrontium (90Sr), but have not been used to make predictions of radiological risk from nuclear accidents under variable environmental conditions on broad geographical scales. In this paper, we first present models for predicting the bioaccumulation of cesium and strontium by aquatic biota based on ambient concentrations of dissolved potassium and calcium, respectively, and then test these models using independent data from aquatic ecosystems at Canadian nuclear sites. Secondly, models yielding the best predictions across a wide range of input parameters were selected to estimate bioaccumulation factors (BAFs) for cesium and strontium in aquatic ecosystems across Canada, using trophic level of organisms and dissolved potassium for cesium and calcium concentrations for strontium as predictor variables, and presented as contour maps of radiological risk. The models show that risk from bioaccumulation of cesium and strontium can vary by several orders of magnitude depending on site-specific environmental conditions and trophic ecology. Overall, our results suggest that single-parameter approaches taken by regulatory standards may either over- or under-predict radiological risk at many locations, and are thus not readily suitable to inform siting decisions for new nuclear developments.  相似文献   

12.
Khan RA  Payne JF 《Chemosphere》2002,46(2):235-239
EROD (ethoxyresorufin-O-deethylase) activity was determined in winter flounder, a sediment-inhabiting and non-migratory fish species, living near a pulp and paper mill in Newfoundland in relation to temperature, gender, sexual maturity, and lesions in the liver. Samples of liver were taken from fish captured by SCUBA divers at 0 degrees C, 5 degrees C and 16 degrees C. Enzymic activity was detected in fish living only above 0 degrees C. Adult males and juvenile fish had higher levels of EROD activity than prespawning females at 5 degrees C. Macrophage aggregates only or occurring simultaneously with bile ductule hyperplasia and clear cell foci in the liver, did not impair EROD activity but necrosis had a negative effect. Results from this study indicate the importance of water temperature, gender, sexual maturity and liver pathology in assessing EROD activity of fish in biomonitoring programs.  相似文献   

13.
The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment.  相似文献   

14.
Experiments were conducted to determine the kinetics and relative importance of aqueous and dietary uptake of cadmium by the freshwater isopod Asellus aquaticus (L.). Test animals were exposed during 30 days to aqueous Cd in a continuous flow system (exposure levels: 0.2 - 10 microg litre(-1)) and kept on a diet of previously contaminated Elodea sp. (range of Cd concentrations: 2-350 microg g(-1), dry weight). Preceding semi-static experiments on dosage-control of the dietary factor revealed a rapid uptake of Cd by Elodea, with relatively high concentration factors (CF), which ranged from 4.8 to 5.5 (dry weight log (CF) after 16 days). For Asellus uptake from water appeared to be the predominant route. Highly significant bioconcentration of cadmium from water was observed in the animals, even at exposure levels below 1.0 microg litre(-1). In the various treatments, direct uptake from water accounted for 50-98% of the body burdens after 30 days exposure. The experimental results were described with a first order one-compartment bioaccumulation model. Model parameter estimates (mean +/- standard error) were obtained for rate constant of uptake (560 +/- 110 day(-1)), rate constant of elimination (0.032 +/- 0.017 day(-1)) and assimilation efficiency of Cd uptake from food (1.1 +/- 0.7%). The (dry weight) bioconcentration factor (BCF) and bioaccumulation factor (BAF) for extrapolated steady state conditions were estimated at 18 000 (BCF) and 0.08 (BAF). Experiments conducted at two different pH levels (5.9 versus 7.6) revealed no significant effects of pH on the uptake of aqueous Cd by the isopods. The results are discussed in relation to their potential significance to the field situation.  相似文献   

15.
A 4year study surveyed 131 lakes across New York State beginning in 2003 to improve our understanding of mercury and gather information from previously untested waters. Our study focused on largemouth and smallmouth bass, walleye and yellow perch, common piscivorous fish shown to accumulate high mercury concentrations and species important to local fisheries. Fish from Adirondack and Catskill Forest Preserve lakes generally had higher mercury concentrations than those from lakes in other areas of the state. Variability between nearby individual lakes was observed, and could be due to differences in water chemistry, lake productivity or the abundance of wetlands in the watershed. We found the following factors impact mercury bioaccumulation: fish length, lake pH, specific conductivity, chlorophyll a, mercury concentration in the water, presence of an outlet dam and amount of contiguous wetlands.  相似文献   

16.
The Chernobyl accident, and the general acidification of Swedish water systems, form the base for this project. The aims of the work have been to present results on the linkage between the concentration of Cs-137 in fish, lake load of Cs and lake characteristics, to give a preliminary prognosis on the recovery, and to put the results within a wider framework of environmental hazard analysis. A broad set of data on limnology, morphometry and drainage area conditions from 41 lakes were collected during 1986 and 1987. Cs-137 was determined in 1 + perch (Cs-pe, 1-year-old perch), water, material collected by sediment traps and from surficial sediments. The main results are as follows. The average value of Cs-pe for all lakes has dropped from 9800 Bq kg(-1) (wet) to 5040 between the 2 years. Generally, the decrease is between 5 and 90%. We have tested if any factor(s) could be specifically linked to this decrease-no such factors have been found. The concentrations of Cs in sediment traps have, on average, decreased by 80%. Very high correlations exist between Cs-pe and the caesium load as determined from the sediment traps. Between 1 and 10% (mean 3.9%) of the initial fall-out deposition to the drainage area was transported from land to water during June to August 1986. The variation in initial fall-out deposition explains 65-69% of the variability in Cs-pe; the degree of explanation (= coefficient of determination, r2) increases to about 85% if one also takes into account the lake water hardness and totP. A map showing with lakes likely to have 1 + perch with higher mean Cs-concentrations than 1500 Bq kg(-1) wet is presented. Between 4000 and 7000 lakes in Sweden appear to have Cs-pe higher than 1500 Bq kg(-1) wet, figures which emphasize the serious impact of the Chernobyl accident on the environmental conditions in Sweden.  相似文献   

17.
A theoretical and experimental study of cation exchange in high ionic strength electrolytes was performed using pristine subsurface sediments from the U.S. Department of Energy Hanford site. These sediments are representative of the site contaminated sediments impacted by release of high level waste (HLW) solutions containing 137Cs+ in NaNO3 brine. The binary exchange behavior of Cs+-Na+, Cs+-K+, and Na+-K+ was measured over a range in electrolyte concentration. Vanselow selectivity coefficients (Kv) that were calculated from the experimental data using Pitzer model ion activity corrections for aqueous species showed monotonic increases with increasing electrolyte concentrations. The influence of electrolyte concentration was greater on the exchange of Na+-Cs+ than K+-Cs+, an observation consistent with the differences in ion hydration energy of the exchanging cations. A previously developed two-site ion exchange model [Geochimica et Cosmochimica Acta 66 (2002) 193] was modified to include solvent (water) activity changes in the exchanger phase through application of the Gibbs-Duhem equation. This water activity-corrected model well described the ionic strength effect on binary Cs+ exchange, and was extended to the ternary exchange system of Cs+-Na+-K+ on the pristine sediment. The model was also used to predict 137Cs+ distribution between sediment and aqueous phase (Kd) beneath a leaked HLW tank in Hanfordd's S-SX tank using the analytical aqueous data from the field and the binary ion exchange coefficients for the pristine sediment. The Kd predictions closely followed the trend in the field data and were improved by consideration of water activity effects that were considerable in certain regions of the vadose zone plume.  相似文献   

18.
螺蛳等供试生物能很快地吸收水体中的^137Cs,并随着时间的延长而不断增加,吸收过程可用直线方程来表达,螺蛳、喜旱莲子草和金鱼藻可以用来净化被^137Cs的吸收较少,其中稗草和喜旱莲子草较高;由于K^+与Cs^+之间的拮抗作用,帮可用施钾肥方法减少作物以土壤中^137Cs的吸收。  相似文献   

19.
Artificial radionuclides, such as iodine-131 (131I), cesium-134 (134Cs), and cesium-137 (137Cs), as well as natural isotopes of beryllium-7 (7Be) and potassium-40 (40K) have been registered in atmospheric aerosols over Vladivostok selected from 11 March to 17 June 2011. Additionally, 134Cs and 137Cs were detected in atmospheric aerosols over Tomsk selected from 16 March to 17 June 2011. Artificial radionuclides were also discovered in atmospheric wet depositions sampled in Vladivostok from 3 to 17 May 2011. Moreover, these radionuclides have been registered in atmospheric aerosols over the sea surface of the Sea of Japan selected from 3 to 31 May 2011 during an expedition of the “Nadezhda” sailing ship. From 18 March to 15 April, an increase in concentrations of atmospheric aerosols over Vladivostok from 108.8 to 321.5 μg/m3 has been registered. It was accompanied by increased activity concentrations of 134Cs, 137Cs, and the 131I. During the period from 18 March to 15 April, activity concentrations of 137Cs and 134Cs in atmospheric aerosols increased 100 times compared with the minimum detectable concentration (MDC) level and peaked in the weekly sample gathered from 8 to 15 April (145.0 and 105.3 μBq/m3, respectively). Variability of concentrations of natural isotopes of 7Be and 40K was not greater than 1 order of magnitude throughout the sampling period. Maximal values of 137Cs and 134Cs concentrations (1,281.5?±?141 and 384.4?±?42.3 μBq/m3, respectively) in Tomsk were reached in samples taken from 1 to 2 April. For the atmospheric aerosol samples from the Sea of Japan, the largest concentration of 131I (392.3?±?215.7 μBq/m3) was detected from 13 to 19 May, while all other samples had much lower concentration values. Synoptic analysis of back trajectories movement of air masses showed that the radioactive cloud came to Vladivostok from the regions of Siberia and northeastern part of China. Synoptic analysis for Tomsk showed that during the period of maximal activity concentrations (1–9 April), air masses were arriving from the European part of Russia and north of Kazakhstan.  相似文献   

20.
The distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals (EDCs) were studied in various tissues of wild fish species from Dianchi Lake, China. In muscle tissue, 4-tert-octylphenol, 4-cumylphenol, 4-nonlyphenol and bisphenol A were detected in fish from each sampling site, with maximal concentrations of 4.6, 4.4, 18.9 and 83.5 ng/g dry weight (dw), respectively. Steroids (estrone, 17β-estradiol 17α-ethynylestradiol and estriol) were found at lower levels (<11.3 ng/g dw) and less frequently in muscle samples. The highest concentrations of steroids and phenols were found in liver, followed by those in gill and the lowest concentration was found in muscle. The field bioconcentration factors (BCFs) of phenols were calculated in fish species ranged from 18 to 97. Moreover, the measured tissue concentrations were utilized in order to estimate water concentration of steroids (4.4-18.0 ng/L). These results showed that steroidal and phenolic EDCs were likely ubiquitous contaminants in wild fish.  相似文献   

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