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1.
- - In the present paper the toxicity of four biocides, endrin, thiodon, malathion and phosvel, has been measured by performing static bioassay experiments with Channa gachua as test fish to establish the median Tolerance Limits (TLm and TL50).
- - The results of bioassay experiments indicate that the fish is harmed even at a very low concentration of these biocides. The values of TLm are 0.0076, 0.0073, 0.00695 and 0.0068 for endrin; 0.01120, 0.01088, 0.01069 and 0.01064 for thiodon; 9.20, 8.10, 7.90 and 7.60 for malathion and 32.90, 32.10, 31.65 and 31.15 mg/l for phosvel for the time interval of 24, 48, 76 and 96 hours, respectively.
- - As indicated by TLm's, endrin is most toxic and phosvel least. Thiodon and malathion came in a descending order between endrin and phosvel.
- - During bioassay studies, the effect of some variables, like temerature, pH and fish-size, on TLm's has also been observed. They gave the following results.
- a) An increase in temperature increased the toxicity of all the biocides.
- b) An increase in pH decreased the TLm as such, making the biocides more toxic to Channa gachua.
- c) For larger fishes, the biocide solutions were less toxic, but the same solutions were more toxic to fishes of a smaller size.
- - The safe harmless concentrations of endrin, thiodon, malathion and phosvel are - 0.00289 mg/l, 0.00337 mg/l, 1.88365 mg/l and 9.16736 mg/l, respectively.
2.
B. S. Khangarot 《洁净——土壤、空气、水》1982,10(3):285-292
Static bioassay tests were carried out on Channa punctatus Bloch in the laboratory after renewal of concentrations every 24 h. The LC50 values and 95 per cent confidence limits were 45.21 (39.62 … 51.11) ppm at 12 h and 29.8 (27.49 … 31.95) ppm of Zn at 96 h of exposure. The actual dissolution values of zinc were also determined in test solutions using an atomic absorption spectrophotometer. Behavioural changes were the higher rate of opercular movements, surfacing, loss of equilibrium and haemorrhage near mouth and caudal fin. The LT50 values indicate that survival was increased with decreasing Zn concentration. The histopathological changes observed due to Zn toxicity in the gills have been discussed in relation to fish mortality. 相似文献
3.
Craig W Steele 《Marine pollution bulletin》1983,14(11):425-428
Sheepshead (Archosargus probatocephalus), Atlantic croaker (Micropogon undulatus) and pinfish (Lagodon rhomboides) were each exposed to aqueous solutions of reagent grade cupric chloride in artificial seawater in four static bioassays. The 24, 48, 72 and 96-h TLm were determined to be, respectively, 4.17, 3.02, 2.19 and 1.14 mg Cu2+·I?1 for sheepshead, 9.15, 7.55, 7.20 and 5.66 mg Cu2+·I?1 for croaker, and 7.33, 4.43, 4.14 and 2.75 mg Cu2+·I?1 for pinfish. These results are compared with literature values of experimental concentrations of copper producing subtle behavioural changes in these species. 相似文献
4.
The present paper deals with the determination of LTm values of zolone, rogor, sumithion and abate for Channa gachua by conducting static bioassay experiments. The TLm values for zolone came out to be 0.08275 mg/l, 0.08225 mg/l, 0.0815 mg/l and 0.0810 mg/l; for rogor 5.155 mg/l; 4.955 mg/l, 4.65 mg/l and 4.475 mg/l; for sumithion 12.60 mg/l, 12.50 mg/l, 12.30 mg/l and 12.20 mg/l and for abate 217.25 mg/l, 225.575 mg/l, 221.575 mg/l and 217.25 mg/l for 24, 48, 72 and 96 hours, respectively. Relative susceptibility indicates that this fish is not susceptible to zolone and less to rogor, sumithion and abate, respectively. Present studies also show that increased temperature and pH increase the toxicity of all the biocides, but increased hardness of water decreases the toxicity of biocide solutions. The safe concentrations for zolone, rogor, sumithion and abate came out to be 0.02437 mg/l, 1.3733 mg/l, 3.6907 mg/l and 66.678 mg/l, respectively. 相似文献
5.
Bengt-Erik Bengtsson 《Marine pollution bulletin》1978,9(9):238-241
The harpacticoid copepod Nitocra spinipes has been tested for acute toxicity of 12 metal chlorides in brackish water. Their order of toxicity, expressed as 96 h LC50, was in good agreement with other investigations performed in freshwater and seawater. The 96 h LC50-values were of intermediate levels compared to these two environments. The organochlorines p,p′-DDE and p,p′-DDE methyl sulphone were tested for effects on reproduction and mortality during two weeks, and it was found that p,p′-DDE was the most toxic. It is concluded from the investigation that N. spinipes is a suitable toxicity test organism in brackish water. 相似文献
6.
The short-term toxicity of mercury, copper and zinc was studied using a freshwater pulmonate snail, Lymnaea luteola (LAMARCK ). The median period of survival increases with decreasing the toxicant concentration. The 96 h LC50 values and their confidence limits were 0.135 (0.112 … 0.186) ppm of Hg2+; 0.172 (0.118 … 0.355) ppm of Cu2+; and 6.13 (5.73 to 7.19) ppm of Zn2+. The relative potency ratio indicates that the Hg2+ ions were most toxic, followed by Cu2+ and Zn2+ ions. 相似文献
7.
《Marine pollution bulletin》1987,18(3):127-131
This study investigated the effects of contamination by copper and freshwater on the behaviour of the estuarine gastropod Polinices sordidus. The burying response was inhibited by both pollutants. In the case of copper, it was suggested that this response after 30 min could reflect toxicity after 96 h, i.e. the 96 h LC50 and the 30 min ED50 were very similar. P. sordidus responded to freshwater at concentrations well below the 96 h LC50, suggesting that this species can detect sublethal concentrations of freshwater. Thus, for salinity, the 30 min ED50 is not a reliable indicator of the 96 h LC50. A linear decline in crawling activity was found in the presence of increasing concentrations of both pollutants. These results for both aspects of behaviour are discussed in the light of results reported earlier for a marine species Polinices incei. 相似文献
8.
Acute toxicity bioassays were conducted on mine tailings produced by pilot plant testing for the proposed Quartz Hill molybdenum mine, which will be situated near Ketchikan, Alaska. Tailings bioassays were conducted in seawater with juvenile coho salmon (Oncorhynchus kisutch), mussel larvae (Mytilus edulis), infaunal amphipods (Rhepoxynius abronius), and euphausiids (Euphausia pacifica). The same general range of mine tailings concentrations was acutely toxic to all four test species with acute effects observed between 61 000 to 277 000 mg l?1 (wet wt) tailings solids (range of 95% confidence limits for LC50 and EC50 values). Chemical analyses of bioassay test solutions and leaching test solutions were conducted for metals (including Cd, Cu, Pb, Zn, Mn and Mo), EPA Priority Pollutant base/neutral organics, and more general parameters such as sulphate, nitrate/nitrite, cyanides, phosphate and ammonia. Parameters possibly contributing to the observed toxicity were complex contaminant mixtures including total suspended solids and heavy metals. The present study provides information related to the marine disposal of mine tailings and shows that these mine tailings present a relatively low level of acutely toxic effects. 相似文献
9.
B. S. Khangarot 《洁净——土壤、空气、水》1981,9(5):505-509
The acute toxicity of copper and copper plus complexing agents to common guppy Lebistes reticulatus was studied for 96 h by a static bioassay technique. The addition of complexing agents viz. disodium salt of EDTA, citric acid, sodium thiosulphate and glycine in Cu2+ solutions caused a great decrease in the per-cent mortality as compared to that of Cu2+ test solutions alone. 10 mg/l of complexing agent was added in each copper concentration in all the test series. The 96 h LC50 values and 95% confidence limits in mg/l of Cu2+ plus were 1.23 (0.95…1.65) for Cu2+ alone; 4.30 (4.04 … 4.55) for Cu2+ plus EDTA; 1.94 (1.69 … 2.18) for Cu2+ plus citric acid; 3.44 (2.96 … 3.74) for Cu2+ sodium thiosulphate and 2.29 (2.22 … 3.02) for Cu2+ plus glycine. 相似文献
10.
Stuart C U&#x;Ren 《Marine pollution bulletin》1983,14(8):303-306
A static renewal toxicity test was conducted to evaluate the response of the copepod Acartia tonsa to bis(tributyltin) oxide (TBTO), the active compound of recently developed antifouling paints. Copepods were individually placed in test tubes containing 4 ml of 0.3, 0.5, 1.0, 1.7 or 3.0 μg l?1 TBTO with acetone and seawater. Thirty copepods were used for each treatment and control condition and all solutions were renewed daily. The 96-h LC50 was 1.0 μg l?1 with a 95% confidence interval between 0.8 and 1.2 μg l?1 TBTO. The 144-h EC50 was 0.4 μg l?1 TBTO which approaches concentrations recently measured in San Diego Bay. Some copepods exposed to 0.3 μg l?1 TBTO became moribund after six days. 相似文献
11.
《Marine pollution bulletin》1987,18(11):600-603
The 24, 96, or 168h LC50s of four used drilling fluids or barite incorporated into sediment were determined in toxicity tests with lancelets (Branchiostoma caribaeum), a benthic chordate. Concurrent to LC50 determinations, EC50s were calculated from the number of lancelets that did not burrow into contaminated sediments. Observations of the burrowing behaviour allowed quantitation of effects after 24h exposures to each of the drilling fluids whereas lancelet mortality was sufficient to calculate 24h LC50s for only one drilling fluid. Drilling fluids were less toxic to lancelets when incorporated into sediments than to mysids (Mysidopsis bahia) or benthic invertebrate communities in water-column exposures. 相似文献
12.
This study investigated the effectiveness of a new packing material, namely mixed rice husk silica with dried activated sludge for removing H2S. Dried sewage sludge was collected from Putrajaya sewage treatment plant in Malaysia. Rice husk silica was prepared at temperature of 800°C, after acid leaching and mixed with dried sewage sludge to be utilized in a polyvinyl chloride filter. The system was operated under variable conditions of two parameters, different inlet gas concentration and different inlet flow rate. H2S was passed through the filter with one liter of the packing material. More than 99.96% removal efficiency (RE) with empty bed residence time (EBRT) of 90–45 s and 300 ppm inlet concentration was observed. However, the RE decreased to 96.87% with the EBRT of 30 s. The maximum elimination capacity (EC) of 52.32 g/m3/h was obtained with the RE of 96.87% and H2S mass loading rate of 54 g/m3/h, while at the RE of 99.96%, maximum EC was 26.99 g/m3/h with the H2S mass‐loading rate of 27 g/m3/h. A strong significant correlation between increasing of H2S mass loading rate and pressure drop was also detected (p < 0.01). Maximum pressure drop was 3.0 mm H2O after 53 days of operating time, the EBRT of 30 s, and 54 g/m3/h of H2S loading rate. These observations suggest that the mixture of rice husk silica with dried activated sludge is a suitable physico‐biological filter for H2S removal. 相似文献
13.
The effect of kerosene and BP 1002 upon the naupliar and adult stages of Balanus amphitrite amphitrite and Balanus variegatus variegatus has been studied. The percentage non-motility and actual mortality of the naupliar larvae and the adults of both species has been generally shown to be a function of the dosage and treatment time of these two hydrocarbons. Both barnacles (nauplii and adults) have a similar susceptibility to the hydrocarbons tested, the nauplii being killed at lower concentrations than the adults. Cirral activity of the adults was significantly reduced when the barnacles were treated with 10 and 100 ppm BP 1002.Preliminary experiments have also been performed to compare the toxicity of BP 1002 and kerosene with that of ‘Bukomkleen’ and ‘Chemkleen’. It was found that BP 1002 was the most toxic to these barnacles with a lower and similar toxicity found for Chemkleen and Bukomkleen. The toxicity of kerosene is comparatively low. 相似文献
14.
Sublethal and lethal effects of biocide Slimicide C-30 on the developmental stages of mussels Mytilus galloprovincialis and juvenile and adult mysid Leptomysis mediterranea were studied.Biocide at a concentration as low as 0.02 mg l?1 caused an incipient effect in the embryonic development of mussels where a decreased number of normally developed larvae from eggs was evident. Slimicide C-30 effective concentration (EC 50/96) was 0.07 mg l?1.In the mysids, the median lethal concentration (96 h LC50) was 0.11 mg l?1.Previous incubation of Slimicide C-30 at 38°C affected a small delay in mortality time (LT50) but did not cause marked change in the acute toxicity to mysids. 相似文献
15.
Short-term tests of the acute toxicity of Cu2+ (from copper sulphate) to a freshwater ostracod, Cypris subglobosa SOWERBY were carried out at five different pH values from 5.5 to 8.5. The toxicity of copper abruptly decreased with an increase in pH of the Cu-containing medium. The 48 h EC50 value of Cu increased from 0.35 ppm at pH =5.5… 5.1 ppm at pH =8.5. The per cent survival, median period of immobilization (ET50), slope functions and the 95 per cent confidence limits were determined at each pH level. The direct correlation between EC50 value and pH indicated that the acute toxicity of Cu decreased as the pH increased from 5.5… 8.5. 相似文献
16.
In static bioassays the toxicity of heavy metal ions against Lymnaea acuminata over 24 … 96 h is tested. The values of the LC50,96h for the metals tested are, in mg/l: Hg2+ ?0.023; Cu2+-0.034, Cd2+ ?0.872, Ni2+ ?2.78, Cr6+ ?5.97 and Zn2+ ?10.49. In the combined solutions of Cu2+, Ni2+ and Zn2+ at least an additive effect of toxicity occurs in the presence of two metals. The same holds for the presence of the three metals; in this case, the relative toxicity against the mixture of two metallic salt solutions appears to be slightly reduced. The acute manifestation of the toxic effect occurs within 48 h, subsequently the relative mortality decreases especially in the mixed solutions. 相似文献
17.
In batch experiments with exposure for 24 to 96 h Macrobrachium naso and M. dayanum were exposed to solutions of the sodium salt of 2,4-dichlorophenoxy acetic acid. The LC50,96h are 2.397 g/l for Macrobrachium naso and 2.275 g/l for M. dayanum. No mortality was observed in solutions of 2.1 and 1.85 g/l. The differences in toxicity are not dependent on the size of the organisms, but they are species-specific. 相似文献
18.
Michael Martin Kenneth E. Osborn Patricia Billig Neil Glickstein 《Marine pollution bulletin》1981,12(9):305-308
Pacific oyster (Crassostrea gigas Thunberg) embryos, bay mussel (Mytilus edulis Linnaeus) embryos, and Dungeness crab (Cancer magister Dana) zoea I stage larvae were exposed to arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc salts. The two bivalve species were exposed through the completion of embryogenesis (48 h), and the effects of the metals upon abnormal development were monitored. The crab larval stages were exposed to the metal solutions for 96 h. Concentrations (μg l.?1 as metal) which caused 50% abnormal development in the two species of bivalve larvae and which were fatal to 50% of the crab larvae ranged from 5.3 (oyster) to 49 (crab) for copper; 5.8 (mussel) to 8.2 (crab) for mercury; 14 (mussel) to 55 (crab) for silver; 119 (oyster) to 456 (crab) for zinc; 232 (crab) to 3000 (mussel) for arsenic; 247 (crab) to 1200 (mussel) for cadmium; 349 (oyster) to 4360 (crab) for nickel; 476 (mussel) to 758 (oyster) for lead; 3440 (crab) to 4538 (oyster) for hexavalent chromium; and selenium greater than 10 000 for the three species. The acute toxicity testing of C. gigas embryo together with two California native species confirmed its usefulness for predicting toxicity to the latter species. 相似文献
19.
Apatite and phosphorus in mantle source regions: An experimental study of apatite/melt equilibria at pressures to 25 kbar 总被引：1，自引：0，他引：1
E. Bruce Watson 《Earth and Planetary Science Letters》1980,51(2):322-335
The solubility of fluorapatite in a wide variety of basic magmatic liquids was experimentally determined over a range of upper mantle P-T conditions (8–25 kbar, 1275–1350°C). Fluorapatite is stable over the entire range of conditions investigated, but its solubility in melts is variable, depending negatively on SiO2 content of the melt and positively upon temperature, with relatively little sensitivity to pressure above 8 kbar. At upper mantle pressures and a temperature of 1250°C, molten basalt (50% SiO2) will dissolve 3–4 wt.% P2O5 before saturation in apatite is reached. For a magma 100°C cooler or containing 10 wt.% more SiO2, apatite saturation occurs at less than 2 wt.% dissolved P2O5. The observed high solubility of apatite in basic magmas at their normal near-liquidus temperatures virtually precludes the occurrence of residual apatite in mantle source regions. If relatively low-temperature melting conditions prevail (e.g., 1100°C), as might be possible in H2O-bearing regions of the upper mantle, apatite could remain in the residue, but only in amounts too small to have significant effects on the rare earth patterns of the liquids.Because of the high solubility of apatite in basic magmas, phosphorus can be confidently treated as an incompatible element in peridotite melting models. Such models, in combination with observed characteristics of basic lavas, indicate that the upper mantle contains ～200 ppm of phosphorus, much less than the chondritic abundance of ～900 ppm. 相似文献
20.
The freshwater catfish, Mystus vittatus, were exposed to the LC50, 96 h dose (i.e. 550 ppm.) of the agro-fertilizer NPK for 96 h, during the spawning period (March–June). Their gonads were biochemically analysed for the total protein content and the free amino acids. The protein content of the gonads of the stressed fish was found lowered. The fish also showed disappearence of certain amino acids from their gonads. 相似文献