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1.
J. Vymazal 《洁净——土壤、空气、水》1990,18(6):657-665
The influence of the duration of exposure on the accumulation of Pb, Cu, Cd, Cr, Co Zn and Ni by Cladophora glomerata was studied in short-term batch experiments. It was determined that the uptake of heavy metals differs not only in the rate of uptake but also in the maximum cumulation attained. The highest uptake after exposure for 6 h to an initial concentration of 200 μg/l occurred with chromium — 168 μg/g, the minimum uptake occurred with cobalt — 86.9 μg/g. Also the rate of uptake differed significantly. After the exposure period of 15 min 120.7 μg/g of chromium was taken up and, in contrast, only 7.6 μg/g of nickel was taken up after the same exposure period. 相似文献
2.
110 samples from two swimming-pools were gas-chromatographically investigated for halogenated hydrocarbons. In spite of varying chlorine concentrations between 0.1 and 2.5 mg/l Cl2 the bacteriological results were unobjectionable. The total of the haloforms was between 1.2 and 182 μg/l, with the average value of 90 μg/l. Besides CHCl3, CHBrCl2, CHBr2Cl and CCl3NO2 there were observed other, still unidentified compounds in the chlorinated bathing water which clearly are successive products of disinfection, too. The water treatment by flocculation and filtration does not bring about any elimination of trihalomethanes. Of special importance is the occurrence of trichloronitromethane in concentrations of 0.13 … 1.2 μg/l, whose LC50 in the Daphnia test is 189 μg/l, at a threshold concentration of 160 μg/l. To limit the pollution of water and air to a minimum, specific conditions must be adhered to in the operation of indoor swimming-pools. 相似文献
3.
A Competitive Immunoassay for the Determination of the Herbicide Fluazifop in Drinking Water and Groundwater A competitive solid-phase enzyme immunoassay using rabbit polyclonal antibodies was developed for the detection of the herbicide fluazifop [(RS)-2-[4-(5-trifluoromethyl-2-pyridyloxy)phenoxy]propionic acid] in drinking water and groundwater. Present regulatory limits for drinking water in Germany were taken as the critical level. The carrier protein was bovine serum albumin; horseradish peroxidase was used as marker enzyme with 3,3′,5,5′-tetramethylbenzidine as substrate. A high concentration of high-affinity antibodies in the serum, optimization of test conditions (antibody and enzyme tracer concentration, incubation time etc.), and very low cross reactivities to substances of similar structures led to a highly sensitive and specific ELISA with a detection limit below 0.1 μg/L for fluazifop as free acid. On testing the suitability of the assay's use as a screening test with one hundred drinking-water samples, the three samples which had been spiked in the laboratory were recognized as positive with respect to their fluazifop content. Confirmation by gas chromatography-mass spectrometry showed the test results of two other samples to be false positive. False negative results did not appear. The concentration was in the detection limit region of 0.1 μg/L. 相似文献
4.
Laboratory reared veliger larvae of the common mussel Mytilus edulis were grown for 15 days in filtered seawater containing 10 μg l?1, 1 μg l?1 and 0.1 μg l?1 tributyltin oxide (TBTO), the biocide in recent antifouling paint formulations. No larvae survived longer than 5 days in 10 μg l?1 TBTO or 10 days in 1 μg l?1 TBTO. Approximately half the larvae subjected to 0.1 μg l?1 TBTO were dead by day 15 (approximate 15 day LC50 = 0.1 μg l?1 TBTO) and most of the surviving larvae were moribund and had grown significantly more slowly than controls. It is noted that current recorded levels of TBT at several UK estuarine sites are higher than 0.1 μg l?1 and there has therefore probably been a high mortality of mussel larvae at such sites. The results are discussed in relation to the reported short-term toxicity of organotins to other marine organisms and the value of carrying out longer-term tests at low levels of TBT is pointed out. 相似文献
5.
Marine prawns (Penaeus japonicus) were exposed to various combinations of chromium and phenol. The yield of prawns was synergistically inhibited by a 63-day exposure to combinations of chromium and phenol, when compared to controls and single-factor treatments. The accumulation of chromium in prawns was not only dependent on the concentration of chromium in the seawater, but was also related to the concentration of phenol in the seawater. The accumulation of phenol in prawns increased with an increase in the concentration of chromium in the seawater, even when the concentration of phenol in the seawater was constant. 相似文献
6.
Particulate matter suspended in the River Severn (Shropshire, UK) consists chiefly of clay-sized mineral particles, together with living and dead micro-organisms (algae and bacteria). Its concentration depends strongly on discharge, but the particle size distribution shows no systematic variability. For most samples, the particle volume is log-normally distributed with respect to diameter, the mean diameter being ca. 9 μm. The particles are mainly aggregates, including some with linear dimensions of the order of tens or hundreds of micrometres. Particle density depends appreciably on size, decreasing from ca. 2.5 × 106 g m?3 at a diameter of 2.5 μm to ca. 1.3 × 106 g m ?3 at 20 μm. The collision efficiency factor for particle aggregation is estimated to be 0.01–0.03. At low discharge, the ‘dead zone’ in the River Severn at Leighton is a well defined region of stagnant water behind a gravel bar. The rate of deposition of fine particles on its bed is of the order of tens of grams per square metre per day. Resuspension requires a critical bed shear velocity of 0.03–0.04 m s?1, which occurs at main river discharges greater than about 150 m3 s?1. Under such conditions the gravel bar is underwater and the dead zone is a region of highly turbulent return flow. A simple mechanistic model of particle dynamics in the dead zone accounts reasonably well for particle accumulation rates when run with parameter values based on measured particle and hydraulic properties. Calculations with the model suggest that most of the sedimentation flux to the dead zone bed is due to particles with equivalent sphere diameters in the range 30–240 μm. Simulations indicate that deposition proceeded continuously during spring and summer, whereas repeated deposition and resuspension occurred in autumn and winter. 相似文献
7.
F. Roos-Barraclough 《Earth and Planetary Science Letters》2002,202(2):435-451
A 14?500 calendar year record of mercury accumulation rates has been obtained from an ombrotrophic peat bog in the Swiss Jura mountains. The range of natural (pre-industrial) mercury accumulation rates varied from 0.3 to 8.0 μg m−2 yr−1. During the Late Glacial and Holocene, climatic and volcanic signals were evident in the mercury record. Mercury accumulation rates increased by a factor of ca 5 during the Younger Dryas cold period. Short-term spikes in mercury accumulation rates, which correspond in time to known volcanic eruptions, occur during the late Boreal and Older Atlantic periods, when volcanic influences on mercury deposition appear to have been intensified due to increased atmospheric humidity. A correlation of mercury to bromine accumulation is observed throughout the pre-anthropogenic period. During the Holocene, mercury accumulation only exceeded the range of this correlation for a few short periods of elevated mercury deposition which correspond to known volcanic eruptions during the Older Atlantic. During historical times, mercury accumulation rates have exceeded the range of the correlation of mercury to bromine continuously since ca 1330 AD. This excess in mercury accumulation is interpreted as an indication of pollution. During the industrial period, mercury accumulation rates reached 107.6 μg m−2 yr−1, of which 84% was mercury that exceeded the correlation range. Mercury accumulation rates peaked again during the 1970s, with 78.8 μg m−2 yr−1. Early 20th century pollution appears to have been dominated by non-Swiss emissions from coal burning, whereas Swiss mercury emissions appear to have been the dominant pollution source during the mid and late 20th century. Current mercury accumulation rates at the site are similar to those ca 10 years ago, with modern deposition rates being ca 15 times their prehistorical average. Anthropogenic emissions of reactive brominated compounds could be contributing to increased atmospheric deposition rates of mercury. 相似文献
8.
The ability of seven hyperaccumulator macrophytes which grow naturally in the heavy metal contaminated channels of three different industries (Hindustan Aeronautical Ltd., Eveready Ltd., and Scooter India Ltd.) to accumulate heavy metals was recorded. All these industries use electroplating processes in their manufacturing and are located in the inner area of Lucknow City, U.P., India. Of the three industries monitored, effluent released from Eveready Ltd. contained the highest concentration of heavy metals. In general, accumulations of heavy metals depend upon the plant species and the metal concentration in the media. All plant samples showed heterogeneous metal accumulations, except for Fe or Cd. It was observed that some plant species accumulated high level of metals, e. g., Eichhornnia crassipes for Fe (4052.44 μg/g), Mn (788.42 μg/g), and Cu (315.50 μg/g), and Spirodela polyrhiza for Cd (12.75 μg/g), Pb (20.25 μg/g), and Cr (128.27 μg/g), even when the metal concentrations were not high in the effluent. In summary, these two plants were found to be the best accumulators at each contaminated site. The results will be helpful in the selection of plant species which can be used as bioaccumulators or bioindicators. 相似文献
9.
The toxicity of Na-pentachlorophenate to Viviparus bengalensis is investigated by batch tests with daily exchange of medium in the temperature range between 19 °C (February), 27 °C (April), 32 °C (June) and 30 °C (August) at times of exposure between 12 and 96 h. In the range of higher concentrations, pronounced abnormalities in behaviour by secreting mucus and discharging eggs and embryos occur. The LC50 are lowest for all times of exposure at 27 °C, whereas the times of survival with a given concentration are highest at 30 °C. From the LC50, 96h, 27°C = 66 μg/l results a safe concentration of only 47 μg/l Na-pentachlorophenate for Viviparus bengalensis. 相似文献
10.
The performance of an existing enzyme immunoassay (EIA) with monoclonal antibodies (mAb) for the determination of terbutryn was improved by the application of a new enzyme tracer. For this purpose the triazine derivative 6-chloro-2-(tert-butylamino)-1,3,5-triazine-4-(6-aminohexane carboxylic acid) was coupled to horseradish peroxidase (HRP). The competitive EIA on microwell plates made it possible to determine terbutryn in the range from 0.05 to 1 μg/L with a 50% B/B0 value of the test at 0.2 μg/L. The application of the EIA to determine terbutryn in spiked surface waters provided good recoveries of terbutryn without matrix effects. 相似文献
11.
Xibai Zeng Shiming Su Xiliang Jiang Lianfang Li Lingyu Bai Yanrong Zhang 《洁净——土壤、空气、水》2010,38(3):238-241
In order to control and remediate arsenic (As) contaminated soil, sediment or water, fungi are used to investigate their potential accumulation and volatilization of As. In this study, after cultivation for 2 days, the dry weights of mycelia for Trichoderma asperellum, Fusarium oxysporum and Penicillium janthinellum all show an increased trend when the As(V) concentration ranges from 0–50, 0–50, 0–80 mg/L, respectively. When the culture system is loaded with 2500 μg As(V), which represents 50 mg/L As, and cultivated for 5 days, P. janthinellum presents the highest efficiency of 87.0 μg/g for As bioaccumulation, and the order of the efficiency for As bioaccumulation is P. janthinellum > T. asperellum > F. oxysporum. However, the order of the amount of volatilized As is F. oxysporum > P. janthinellum > T. asperellum, and the highest amount of volatilized As is observed for F. oxysporum at 181.0 μg. Thus, the ability of As bioaccumulation and biovolatilization for T. asperellum and P. janthinellum is reported for the first time in this study. 相似文献
12.
The plankton collected from three fish ponds shows a considerable variability within a pond, between the ponds and in the course of the year. The individual volumes or weights are (minimum—mean—maximum): Gleotrichia echinulata 41–252–879 μg3, Chlorella vulgaris 18–42–94 μm3, Oscillatoria amphigranulata 99–306–827 μm3, Brachionus plicatilis 1–4.918 μg, nauplia 0.5–1.25–2.35 μg, Mesocyclops hyalinus 4–45–369—μg, Heliodiaptomus viduus 41–202–288 μg, Daphnia carinata 186–1468–4578 μg. 相似文献
13.
The clam Ruditapes decussatus L. was collected from Ria Formosa, Faro, southern Portugal, and exposed to a sublethal copper concentration of 0.01 mg l−1 for 20 days. Physiological measurements, respiration rates, clearance rates and absorption efficiency, were undertaken initially and after 2, 5, 9, 14 and 20 days and used to calculate Scope for Growth. Copper accumulation rate was calculated through the analysis of copper in the tissues at the same sampling times. The experiment showed two phases. Initially, copper was rapidly accumulated (1.95 μg Cu g−1 dw day−1 in the first 48 h), clearance rates declined markedly (lowest value 13.5% of control) and respiration rates increased (116% of control), resulting in a rapid decline of Scope for Growth, which showed a negative value after 5 days. In the second phase, (from day 9 on), the rate of copper uptake declined to 0.55 μg Cu g−1 day−1 and physiological responses were more stable. After 20 days, copper concentration in the tissues was 38.4 μg Cu g−1 dw (bioconcentration factor 3840). Clearance rates were 50% of control rates and respiration rates were still high, 145% of control rates. Therefore, Scope for Growth and performance of the clams was still greatly affected (ca. 23% of the control values), indicating that though animals partially recovered through detoxifying mechanisms, excess copper caused sustained impairment of physiological functions. This experiment confirms that the physiological energetics approach and the integrated Scope for Growth measurement is a sensitive methodology to detect deviations from normal performance and assess stress at environmental realistic copper concentrations. 相似文献
14.
Behaviour of Some Pharmaceuticals during Artificial Groundwater Recharge – Elimination and Effects on Microbiology The behaviour of bezafibrate, carbamazepine, clofibric acid, diclofenac, ibuprofen, and gemfibrozil during artificial groundwater recharge was investigated with different test systems simulating field conditions. The given concentrations of the pharmaceuticals were 100 μg/L in the influent of the systems. Concentrations in the influent as well as in the effluent were measured by GC‐MS. These column experiments indicated a significant elimination of bezafibrate, diclofenac, and ibuprofen (60 to 80%) during slow sand filtration. The results showed a moderate elimination of clofibric acid and gemfibrozil (40 to 60%) but a rather low elimination of carbamazepine (<40%). The adaptation times until the elimination processes started were about 5 days. Only the elimination of carbamazepine needed a lag phase up to 17 days. Additional column experiments with groundwater model systems indicated a high persistence of pharmaceuticals under aerobic and anaerobic groundwater conditions. The elimination was less than 20%. Only diclofenac was eliminated with rates between 60% and 80% in aerobic systems and between 40% and 60% in anaerobic systems. Analysis of eubacterial 16S‐rDNA by PCR and DGGE demonstrated changes in the microbial community structure in slow sand filters after application of pharmaceuticals. Adaptation processes may cause these changes, e.g. the appearance or disappearance of single species. Also differences between the populations of water and of the solid phase in slow sand filters could be demonstrated by DGGE pattern. 相似文献
15.
Lucie Bláhová Pavel Babica Eliška Maršálková Blahoslav Maršálek Ludek Bláha 《洁净——土壤、空气、水》2007,35(4):348-354
The first outcomes of the national monitoring program on cyanobacteria and their toxins in the Czech Republic are reported. The concentrations of extracellular microcystins (MCs, analyzed by ELISA) in 206 water samples collected from 94 localities have been investigated. Observed MC concentrations were relatively high in comparison with the literature data, although weather conditions during the covered season (year 2004) were less favorable for the cyanobacterial water blooms. Detectable MCs (>0.125 μg/L) were found in 145 waters (70% of all samples) with a median concentration of 0.67 μg/L. The total median, including samples with no detectable MCs, was 0.26 μg/L. The seasonal trend showed an increase from July to September at most localities (maximum concentrations of about 8 μg/L and extremes up to 37 μg/L). However, a peak at the beginning of the season or continuously elevated MC concentrations were also observed at some localities. Positive correlations between increasing concentrations of MCs and the dominancy of Microcystis spp. have been observed. The survey provides the first large-scale study of the occurrence and seasonal variability of extracellular microcystins that are of particular interest for drinking water management. 相似文献
16.
— The 96 h TL50 values, the maximum acceptable toxicant concentration (MATC) and the safe concentrations were determined for various aquatic pollutants, viz. thiotox, chlordane, metasystox, dichlorvos, sevin and carbofuran (pesticides), phenol, pentachlorophenol and dinitrophenol (phenolic compounds), cadmium chloride and copper sulphate (heavy metal), swascofix P14, swanic 6 L and swascol 1P (synthetic detergent) using the larvae (the most sensitive stage of the life cycle) of Cyprinus carpio, a fresh water exotic carp. — The estimated MATC ranged between 0.009 and 400 μg/1 for all the pollutants; — the calculated value of the application factor (AF) ranged between 0.0096 and 0.0978. — The safe concentrations were determined for each pollutant by the lowest value of application factor worked out in the present investigation; — safe concentrations were also worked out by different formulae given by different workers. The values obtained were compared with the safe concentrations value worked out by the authors of the present study. 相似文献
17.
Urban populations are exposed to a high level of fine and ultrafine particles from motor vehicle emissions which affect human health. To assess the hourly variation of fine particle (PM2.5) concentration and the influence of temperature and relative humidity (RH) on the ambient air of Lucknow city, monitoring of PM2.5 along with temperature and RH was carried out at two residential locations, namely Vikas Nagar and Alambagh, during November 2005. The 24 h mean PM2.5 concentration at Alambagh was 131.74 μg/m3 and showed an increase of 13.74%, which was significantly higher (p < 0.05) than the Vikas Nagar level. The 24 h mean PM2.5 on weekdays for both locations was found to be 142.74 μg/m3 (an increase of 66.23%) which was significantly higher (p < 0.01) than the weekend value, indicating that vehicular pollution is one of the important sources of PM2.5. The mean PM2.5 at night for all the monitoring days was 157.69 μg/m3 and was significantly higher (p < 0.01) than the daytime concentration (89.87 μg/m3). Correlation and multiple regressions showed that the independent variables, i. e., time, temperature, and RH together accounted for 54%, whereas RH alone accounted for 53% of total variations of PM2.5, suggesting that RH is the best influencing variable to predict the PM2.5 concentration in the urban area of Lucknow city. The 24 h mean PM2.5 for all the monitoring days was found to be higher than the NAAQS recommended by the US‐EPA (65 μg/m3) and can be considered to be an alarming indicator of adverse health effects for city dwellers. 相似文献
18.
Monocrotophos (0,0-dimethyl-0-(1-methyl-2-N-methyl-carbamoyl)-cis-vinylphosphate) as an active component of some insecticides is highly soluble in water at a low hydrolysis rate: half-time at 2 mg/l, pH = 7.0 and 38 °C 23 d. Individuals of the following fish species (individual weight in g) were kept during the static bioassay for 6… 72 h at 40 mg/l monocrotophos in the medium: Cyprinus carpio (70), Carassius carassius (45) and Leucaspius delineatus (1.5), and then the concentration of monocrotophos was gas-chromatographically determined in different tissues. Initially, till the 24th hour a high accumulation in the gills took place (in mg/kg fresh weight: Cyprinus 0.49, Carassius 3.88), then the concentration remained uniform or slightly falling here, whereas in the other organs (digestive organs, muscle, gonads) a further accumulation up to 1 mg/kg occurred. Leucaspius was investigated only as whole individuals, and after 72 h their fresh weight had increased to 6.96 mg/kg. The rates of accumulation decrease in the following order: Cyprinus: digestive organs, gills, muscle; Carassius: gills, digestive organs, gonads, muscle. 相似文献
19.
There is determined the LC50 for 24 … 96 h of phenol, 2,4-dinitrophenol and pentachlorophenol as sodium salt by static assay at water temperatures of 16, 23 and 36°C. In addition, the combinations of the three substances were tested in the same way. With decreasing temperature, the toxicity of the individual substances decreased by 6.5 … 22%, that of the mixtures by 10 … 87%; with rising temperature, the toxicity increased by 38 … 747% and 75 … 744%, respectively. The safety limits at 23°C lie between 0.3 μg/l for a synergistically acting mixture and 0.9 mg/l for an antagonistically acting one; for the individual substances this range is 3.5 μg/l to 0.5 mg/l. 相似文献
20.
The present study was undertaken to investigate the accumulation of microcystins (MCYST) in the various tissues of an endemic and protected fish species (Rutilus panosi). We also tried to identify any differences in sensitivity and accumulation of MCYST, for various specimens of the same fish species related to body length. MCYST concentrations in lake water and fish tissues were determined by a commercial Microcystin ELISA kit. Results showed that considerable amount of toxins were found to be accumulated in tissues of R. panosi throughout the year. Among them, liver had the highest MCYST concentrations (407.97 ± 32.43 ng/g). This study confirmed the accumulation of high MCYST concentrations in fish brain (308.75 ± 26.49 ng/g). Our results suggest, that MCYST accumulation in R. panosi tissues is size depended. High MCYST concentration in the muscle of the fish increases the risk of unsafe consumption, thus threatening human health. 相似文献