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1.
The effects of acidic medium on the fry of Cyprinus carpio have been studied. The eggs of Cyprinus carpio were obtained from the Bilawali Fish Farm, Indore M.P. in July 1976. The eggs were put in various concentrations of HCl ranging from 0.0025 ppm to 0.0500 ppm. One specimen from each experimental group was sacrificed for histological studies every week. The microtomy sections were studied under high power. It was found that when the fries were kept in acidic medium following changes took place:
- - Nucleus became inconspicuous and cell wall became disorganised;
- - muscle layers of gut wall became indistinct and disorganised to some extent;
- - epithelial lining of the gut was partially destroyed.
- - vacuolation in the connective tissue of gut was seen due to destruction of some of the cells;
- - hepatic cells of the liver were destroyed at various spots to a varying degree.
2.
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
3.
The effect of different concentrations, viz. 0.01, 0.001 and 0.0001 ppm of methyl mercuric chloride on survival, growth behaviour and chlorophyll content of Chlorella vulgaris has been studied under various environmental conditions. Methyl mercury at 0.01 ppm is 100% toxic to the test alga. At a sublethal (0.001 ppm) dose of CH3HgCl, Chlorophyll a was more inhibited than Chlorophyll b. Toxicity was found to be very much under the influence of pH as at acid pH growth is highly reduced by a sublethal concentration, whereas the same concentration does not have an inhibitory influence in the alkaline range of pH. Eutrophic waters seem to reduce the heavy metal toxicity in general. 相似文献
4.
D. K. Verma 《洁净——土壤、空气、水》1991,19(3):327-329
Laboratory acclimated Labeo rohita, common fresh water edible fish, were exposed to a sublethal concentration (2.5 ppm) of DDT for 2, 4, 8, 16 and 32 days. Residues of three isomers of DDT were estimated in the kidney of Labeo rohita using the gas liquid chromatographic technique. The maximum residues of DDT, DDE and DDD were 1.4327, 0.4172 and 0.2913 ppm, respectively. The total DDT residues concentration was 2.1412 ppm on the final day of the experiment. The tabulated tcalculated t at all intervals. 相似文献
5.
- - 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.
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.
The effects of chronic exposures to sublethal concentration of two pesticides Carbaryl and Endosulfan on alkaline and acid phosphatase activities in the intestine of a fresh water teleost Channa striatus have been observed by exposing the fish for a period of two to thirty days to 10 ppm and 20 ppm of Carbaryl and 0.00075 and 0.001 ppm of Endosulfan. The inhibition of alkaline phosphatase activity has been dependent on the duration of exposure, concentration and the type of pesticide used. The acid phosphatase activity increased with the duration of exposure in higher concentration of Carbaryl and both the concentrations of Endosulfan. Endosulfan produced more pronounced effects than Carbaryl. 相似文献
8.
Alava JJ Ross PS Ikonomou MG Cruz M Jimenez-Uzcátegui G Dubetz C Salazar S Costa DP Villegas-Amtmann S Howorth P Gobas FA 《Marine pollution bulletin》2011,62(4):660-671
We characterize for the first time the presence of DDT and its metabolites in tropical Galapagos sea lions (Zalophus wolleabeki). ∑DDT concentrations in Galapagos sea lion pups sampled in 2005 and 2008 ranged from 16 to 3070 μg/kg lipid. Concentrations of ∑DDT in pups in 2008 averaged 525 μg/kg lipid and were 1.9 times higher than that (281 μg/kg lipid) detected in pups in 2005. These concentrations are lower than those reported in many pinnipeds elsewhere, comparable to those in Hawaiian monk seals, and higher than those in southern elephant seals. The health risk characterization showed that 1% of the male pups exceeded the p,p′-DDE toxic effect concentration associated with anti-androgenic effects reported in rats. The findings provide preliminary guidance on the relationship between DDT use and ecological impacts, serving as a reference point against which possible future impact of tropical DDT use can be assessed. 相似文献
9.
This paper presents the results of a 6-year (1998–2003) survey of trace toxics in the intertidal mussel Perna viridis conducted by the Hong Kong Environmental Protection Department. Concentrations of heavy metals and trace organics were measured in the soft bodies of P. viridis collected from five sites in Hong Kong waters, i.e. Wu Kai Sha (Tolo Harbour), Ma Wan (Northwest), Tsim Sha Tsui (Victoria Harbour), Tai Tam (Hong Kong South) and Lamma Island (Southern Waters) in order to establish the spatial patterns of contaminants in mussels. Among the metals analysed, Cd showed a significant concentration gradient in Hong Kong waters. The levels of Cd in P. viridis were significantly higher at Ma Wan as compared to the other sites studied. Ma Wan also had relatively higher concentrations of Pb. Mn concentrations were particularly prominent at Wu Kai Sha. Significantly higher concentrations of Hg and Cu were recorded at Tai Tam and Tsim Sha Tsui. Tai Tam and Wu Kai Sha had higher levels of V; whereas higher Ni concentrations were recorded at Lamma Island and Tai Tam. No clear spatial patterns for Al, As, Cr, Fe and Zn were observed.Higher concentrations of PAHs in P. viridis were observed around urban centres impacted by sewage discharges (e.g. Tsim Sha Tsui); whereas higher PCB levels were found not only in Tsim Sha Tsui but also in less urbanised areas such as Lamma Island and Tai Tam, suggesting that these may be due to non-sewage related inputs. The study also shows that Northwest and Southern waters are subject to a higher degree of DDT pollution compared with other sites. Of the 17 dioxin compounds analysed, positive data were mostly recorded for two compounds which are of low toxicity (i.e. OCDD and 1,2,3,4,6,7,8-HpCDD) whereas the most toxic congeners (i.e. 2,3,7,8-TCDD and 1,2,3,7,8-PeCDD) were not detected in the 6 years of monitoring. In general, the levels of OCDD in P. viridis were found to be higher in Tai Tam and Lamma Island in Southern Waters of Hong Kong.This study found that the levels of some highly toxic heavy metals (i.e. Cd, Hg and Pb) in the mussel P. viridis did not exceed the recommended limits for shellfish as food in Hong Kong (i.e. Cd: 2.0 ppm; Hg: 0.5 ppm; Pb: 6.0 ppm wet weight). The levels of As and Ni in P. viridis were also well below the action limits set by the US FDA (i.e. As: 86 ppm; Ni: 80 ppm wet weight). DDT and PCB contaminations in P. viridis were below the concentrations of concern. Compared with data obtained in the 1980s, the current levels of DDTs in P. viridis were 4–16 times lower; whereas Pb concentrations recorded in Tsim Sha Tsui have also been lowered significantly. This is mainly related to reduction in local and regional pollution sources in the past 20 years. 相似文献
10.
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
11.
The exposure of catfish, Heteropneustes fossilis to different concentrations (200, 500, 700, 1000, 1500, 2000 ppm) of crude oil extract for a varying period (for up to 48 h in lethal extract and 360 h in sublethal one) resulted into a number of haematological changes. All the parameters taken here were found to have been increased except the haemoglobin level which fell down to 14.3 % in an acute lethal concentration (2000 ppm) after 48 h of exposure. The haematocrit value increased significantly (12 %) in 2000 ppm. The blood sugar level showed hyperglycemia in all the concentrations. The increase in ascorbic acid (28 %) was pronounced in higher concentrations. Changes occurring in different parameters seemed to be reversible as all the parameters returned to their normal levels after returning the fish to normal media, except the nuclear swelling which did not resume the normal functioning even after a prolonged treatment (1 month or more) in the recovery jar. The haematological effects shown by the crude oil resembled partly those kept in severe hypoxic conditions and partly to the fishes poisoned by heavy metals (Cu and Zn). On the basis of results obtained in this investigation, crude oil may be categorised as a complex toxic agent. 相似文献
12.
An attempt has been made to study the toxicity of two commonly used pesticides aldrin (organochlorine) and ethyl-parathion (organophosphorus) to the fish Colisa fasciatus (Anabantidae) and Notopterus notopterus (Notopteridae). During bioassay studies, the behaviour of the fishes was recorded. The aldrin concentration used lies between 0.021 mg/1 and 0.042 mg/1 for C. fasciatus and 0.00056 mg/1 and 0.00135 mg/1 for N. notopterus. The ethyl-parathion concentration used lies between 1.8 mg/1 and 3.7 mg/1 for C. fasciatus and 0.49 mg/1 and 1.00 mg/1 for N. notopterus.
- – The effect of lethal aqueous concentrations of pesticides on the Fishes prior to death are usually manifested by excitation, erratic swimming ability, difficulty in respiration, increasing in ventilation rate, jerky movements of body and fin fast, up- and downward movements, convulsions, loss of equilibrium, loss of the original colour of the body skin and the excess secretion of mucus by the gills and the body wall.
- – the TLm values for 24, 48 and 96 hours of exposition are determined for both species of fish and both pesticides at the following variables:
- ? three levels of temperature,
- ? three levels of dissolved oxygen,
- ? three levels of pH,
- ? three fish sizes.
- – statistical analysis of variance shows, that all variables have a significant effect on the TLm values of both pesticides for both fish species;
- – Aldrin (chlorinated hydrocarbon) is more toxic than ethylparathion (organophosphate) at all variables;
- – Colisa fasciatus is the more resistant species than Notopterus notopterus.
- – the relationship between the total number of the fishes N0, survival numbers N and time t can be expressed by a mathematical formula as:
- – the harmless concentration to C. fasciatus ranged from 0.0049 mg/1 to 0.0161 for aldrin, 0.54 mg/1 to 0.99 mg/1 for ethyl-parathion and to N. notopterus from 0.00012 mg/1 to 0.00045 mg/1 for aldrin, 0.10 mg/1 to 0.21 mg/1 for ethyl-parathion;
- – the aldrin should be diluted at least 4000 times and ethyl-parathion 320 times of its actual concentration.
13.
J. L. Cheminee 《Bulletin of Volcanology》1970,34(1):168-195
Concentrations in uranium, thorium and potassium were determined by gamma spectrometry in more than 100 samples of volcanic rocks from the material obtained during the French-Italian expedition in Dankalia (Afar-Ethiopia) (December 1967 – February 1968). These samples were taken from two geographically distinct areas: in the Erta Ale range, for basalts, K: 0,5%, U: 1,3 ppm, Th: 3,3 ppm, Th/U: 2,6. for alkaline rhyolites, U: 4,1 ppm, K: 2,3%, Th: 15,2 ppm, Th/U: 3,7. in the Pierre Pruvost massif, for acid rocks, K: 3,9%, U: 3,6 ppm, Th: 13,5 ppm, Th/U: 3,8. in the Borawlu centre, K: 2,8%, U: 4,6 ppm, Th: 14,7, Th/U: 3,4 for the rhyolites, K: 0,6%, U: 0,9 ppm, Th: 3,1 ppm for the basalts. on the Ethiopian high lands, for the Adigrate basaltic trap rocks, K: 0,6%, U: 0,6 ppm, Th: 1,1 ppm, Th/U: 1,7 and for the Axum zone of phonolitic pinnacles, K: 3,9%, U: 2,7 ppm, Th: 14,9 ppm, Th/U: 4,9. The Th/K and U/K ratios are particularly high compared with the usual data, except for the Pierre Pruvost massif which seems to be different from the others. The difference of Th/U ratios for basic rocks and acid rocks is meaningful. For the magma which gave the volcanism of the studied area, one can think of an evolution more especially connected with transfers of volatile elements. The strong correlations existing between potassium, uranium and thorium probably indicate the presence of groups which are distinct from a geochemical point of view in the Dankalia lavas. 相似文献
- the danakile depression (Erta Ale range, Pierre Pruvost massif, Alayta, Afdera, Borawlu).
- Ethiopian high lands (Adigrate — Axum).
Dash
14.
The Vistula (Wisla) river, the biggest river in Poland, is 1038 km long and has a drainage area of 168 689 km2. The river is strongly polluted by wastewaters. Big industrial plants are situated mainly in the upper part of the river, where it is slow‐flowing. This paper presents the results of the analysis of bottom sediment samples gathered from different locations along the Vistula river, from Kraków to Gdansk. The study was conducted in 2005. The following parameters were determined: chloroorganic pesticides, polychlorinated biphenyls (PCBs), chlorophenols, polycyclic aromatic hydrocarbons (PAHs), total organic carbon (TOC). The sum of chloroorganic pesticides was in the range of 2.0 to 77.5 ng/g d.w. (dry wet) with the highest values in the upper part of the river. p,p′‐DDT was found in the highest concentration. The sum of PCBs was in the range of 0.9 to 64.2 ng/g d.w. The sum of chlorophenols varied from 0.48 to 14.3 ng/g d.w. 2,4‐Dichlorophenol and pentachlorophenol occurred in the highest concentration. The sum of PAHs was in the range of 1552 to 7832 ng/g d.w. Phenantren was found in the highest concentration and antracen in the lowest. TOC values varied from 4.3 to 43.9 g/kg d.w. The concentrations of pesticides and PCBs were the highest in the upper part of the river and decreased along the course of the river, but the other determined compounds did not show this trend. However, the highest values occurred always in the upper part of the river. 相似文献
15.
Residues of four chlorinated hydrocarbons, viz. Aldrin, BHC, DDT and Endosulfan, were estimated in twenty fresh water edible fishes using a gas chromatographic technique. The residue accumulation showed a definite relation with the feeding habits of fishes. Omnivorous fishes were found highly contaminated, followed by carnivorous and herbivorous species. Heteropneustes fossilis was the highly contaminated fish with residue concentrations of Aldrin (0.051 ppm), BHC (0.814 ppm), DDT (1.962 ppm) and Endosulfan (0.312 ppm). 相似文献
16.
I. A. Ansari 《洁净——土壤、空气、水》1987,15(4):433-435
The free amino acids of the liver and muscle of C. punctatus exposed to 1 ppm of copper sulphate solution up to 84 days were investigated. Few amino acids, notably cystine and tryptophan, disappeared and few new amino acids appeared. These changes in the free amino acids may be due to toxic effects of copper sulphate leading to rancidity in the fish. 相似文献
17.
The problem of a plane wave incident on a non-isotropic dipping layer lying over an isotropic conducting substratum has been studied and some numerical results are presented to show the effects of
- 1) degree of anisotropy m,
- 2) conductivity contrast between the substratum to the upper layer b,
- 3) angle of inclination of the axis of anisotropy α,
18.
以泥鳅（Misgurnus anguillicaudatus）、铜锈环棱螺（Bellamya aeruginosa）、河蚬（Corbicula fluminea）为受试生物,以死亡率、渗血率、体质量变化、行动迟钝率、挖洞率为测试指标,探究沉积物中Zn和Cd对底栖生物的21 d慢性毒性效应,并对鄱阳湖Zn和Cd的沉积物基准值进行了验证.结果表明,沉积物中Cd对底栖生物的毒性效应强于Zn,沉积物中Zn、Cd对泥鳅、铜锈环棱螺、河蚬的LC50（半数致死浓度）分别为644和61 mg/kg、751和54 mg/kg、652和81 mg/kg,EC50（半数效应浓度）值分别为526和49 mg/kg、589和35 mg/kg、474和45 mg/kg.经验证,沉积物Zn和Cd的TEL（临界效应浓度）、PEL（必然效应浓度）值比较合理,具有一定适用性,即当Zn、Cd的加标含量低于TEL值时,QTEL<1,不具有毒性;当加标含量高于PEL值时,QPEL>1,毒性明显. 相似文献
19.
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
20.
From the biological data presented here it is difficult to define any species of fish as an indicator of pollution in the strict sense. Nevertheless, the following generalizations are possible.
- - Species as Wallago attu, Clarias batrachus, Heteropneustes fossilis, Ophiocephalus striatus and Oph. punctatus occur in good number in the polluted stretch and seem to be tolerant species.
- - The species as Esomus danrica, Labeo rohita, Labeo gonius, L. bata, Catla catla, Cirrhina mrigala, Barbus chagunio, Barbus spec., Notopterus notopterus and Mugil corsula are most sensitive and disappear first in the polluted stretch.
- - The species as Barilius bola, B. bendelisis, Nemacheilus latius, Notopterus chitala, Collichrous bimaculatus, and Nandus nandus are moderately sensitive.
- - It appears that the main damage is caused to carp and feather-back fishes. The whole stretch of heavy pollution is almost devoid of carp and featherback.
- - The higher number of protozoans, chironomids, maggots and the decrease in the number of mollusca can be considered as the indicator of pollution, because of their abundance in polluted zones.
- - Chlorella, Lyngbya, Gyrosigma and Euglena (algae), Viviparius (mollusc) and Bosmina (crustacea) are very sensitive to pollution.
- - Oscillatoria, Pandorina, Anabaena, Nitzschia, Closterium (algae), Branchionus, Rotatoria (rotifers) and Naidium (annelid) are moderately sensitive.
- - Synedra, Spirogyra, Desmidium, Rivularia, Navicula, Fragillaria Phacus, Arcella and Vorticella are fairly tolerant forms.
- The stretch studied has been subdivided into five zones with characteristic features:
- - The Oligosaprobic Zone - characterized by a sufficient oxygen saturation, low B. O. D. and C. O. D., with a good fauna and flora.
- - The Polysaprobic Zone - with low oxygen saturation, high B. O. D. and C. O. D. and hydrogen sulphides with a restricted fauna and flora.
- - The α-Mesosaprobic zone - with moderate oxygen saturation, moderate B. O. D. and C. O. D. traces of hydrogen sulphide with the improvement of the fauna and flora.
- - The β-Mesosaprobic Zone - with fair oxygen saturation, low B. O. D. and C. O. D., with the reappearence of fauna and flora.
- - The Oligosaprobic Zone - similar to the zone of low pollution in all characteristics.