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1.
Mutagenic and genotoxic effects of polycyclic aromatic hydrocarbons, anthracene and benzo [a] pyrene (BaP), in milkfish Chanos chanos were determined using micronucleus (MN) test and comet assay (CA). Distinct mean frequencies of nuclear abnormalities such as MNs; binucleated micronuclei, nuclear bud, and fragmented apoptotic cells were measured. Significant increase in DNA damage with five classes of damage level was observed and expressed in terms of arbitrary unit (AU). Mean frequencies of total nuclear abnormalities were 0.5?±?0.25 cells in control; 0.67?±?0.33 cells in solvent control; 70?±?9.60 cells in 0.176?mg?L?1 anthracene, and 91.83?±?6.25 cells in 0.031?mg?L?1 BaP. The greatest DNA damage of 170AU was observed in 0.176?mg?L?1 anthracene-exposed group and 182AU was observed in 0.031?mg?L?1 BaP-treated fish. This study confirmed that the CA and MN assays are useful tools in determining potential genotoxicity of water pollutants and might be appropriate as a part of monitoring program.  相似文献   

2.
Ammonia toxicity tests were performed with Labeo bata (bata) larvae of three different size groups. One hundred percent survival of larvae (500.0?±?4.0?mg) was recorded when exposed to ammonia concentrations of 1.0–13.56?mg?L?1 at 96?h of exposure. Bata larvae exposed to ammonia concentrations of 15.8–25?mg?L?1 showed 10–74% mortalities. The 96?h LC50 value for 200 (±5), 250 (±2) and 500 (±4) mg bata larvae were 11.5, 16.8 and 22.5?mg?L?1 un-ionised ammonia concentrations, respectively. When fish were exposed to different doses of ammonia, behavioural changes immediately occurred even at the lowest dose. At first, the fish became hyperexcitable, the skin darkened and they showed an increased ventilation frequency, fish behaviour became normal, 24?h after exposure. A 96?h LC50 value of un-ionised ammonia showed direct relationship with the increasing size of bata larvae.  相似文献   

3.
The effect of calcium and magnesium either singly or in combination on accumulation of cadmium and copper in Labeo rohita (rohu) and Catla catla (catla) was investigated in this study under laboratory conditions. The investigation showed that copper accumulation in rohu exposed to 0.25 mg L?1 of copper for 14 days reduced from 31.0 ± 0.4 mg kg?1 at no calcium/magnesium treatment to 3.5 ± 0.2 and 2.2 ± 0.1 mg kg?1, respectively, at 75 mg L?1 calcium or magnesium treatment. The copper level in catla exposed to 0.20 mg L?1 of copper for 14 days reduced from 5.7 ± 0.1 mg kg?1 at no calcium/magnesium treatment to 3.4 ± 0.2 and 3.3 ± 0.1 mg kg?1, respectively, at 300 mg L?1 calcium or magnesium treatment. The cadmium accumulation in rohu exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 1.7 ± 0.1 mg kg?1 at no magnesium treatment to 1.4 ± 0.1 mg kg?1 at 120 mg L?1 magnesium treatment. The cadmium accumulation in catla exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 0.8 ± 0.2 mg kg?1 at no magnesium treatment to 0.6 ± 0.2 mg kg?1 at 80 mg L?1 magnesium treatment. Copper and cadmium treatments also reduced some essential microelements of rohu and catla. Both the fishes restored these elements at different levels of calcium and magnesium.  相似文献   

4.
Metal pollution produces damage to marine organisms at the cellular level possibly leading to ecological imbalance. The present investigation focused on the acute and chronic toxicity of lead (Pb) and zinc (Zn) by examining the effects of biomarker enzymes in post-larvae of Penaeus monodon (Tiger prawn). Antioxidant biomarker responses such as lipid peroxidation (LPO) and catalase (CAT) activity for Pb and Zn were determined following chronic exposure. Acute Lethal Concentration 50 (LC50) values observed in the study at 96?h for Pb and Zn at 5.77?±?0.32?mg?L?1 and 3.02?±?0.82?mg?L?1, respectively. The estimated No Observed Effect Concentration and Lowest Observed Effect Concentration values for Pb were 0.014 and 0.029?mg?L?1 and that recorded for Zn was 0.011 and 0.022?mg?L?1, respectively. Among the two metals studied, toxicity of Zn was found to be greater to P. monodon than Pb. The activities of antioxidant defense enzymes and total protein content differed significantly from control following exposure to both metals. Overall, the biomarker studies demonstrated that alterations in antioxidant enzymes and induction of LPO reflect the consequences of heavy metal exposure in P. monodon.  相似文献   

5.
The study aimed to examine the contamination status of arsenic (As) in excavated small water bodies, commonly known as ponds – the integral part of daily life in the arsenic-affected rural areas of West Bengal, India in comparison to the unaffected areas. The ponds of the contaminated area had higher levels of As: water 2–174 µg L?1 (mean 31 ± 2 µg L?1) and sediment 1.3–37.3 mg kg?1 (mean 10.3 ± 0.4 mg kg?1), than those from the unaffected area: water 1–8 µg L?1 (mean 4 ± 0 µg L?1) and sediment 1.4–5.3 mg kg?1 (mean 3.0 ± 0.1 mg kg?1). A moderate positive correlation was observed between the water and sediment arsenic content of the ponds of the arsenic-affected region (r = 0.688, n = 277, p < 0.0001). Contaminated ground water, either as direct input or through agricultural washings, was found to be the major contributor of arsenic pollution to these ecosystems. Seasonal variations were not prominent. This study emphasized the beneficial role of using the studied ecosystems over the highly contaminated ground water for various livelihood activities in the Gangetic delta region.  相似文献   

6.
The study involved assessing the potential of the native plant species (Berkheya coddii) for the phytoextraction of nickel, palladium, and platinum contaminated sites. Plant and soil samples were randomly collected from Barberton area, near Agnes mine, Mpumalanga Province, South Africa. Samples were analysed for total nickel, palladium, and platinum concentrations together with other elements found in the soil and in the plants' roots, and leaves. Soil versus leaves and soil versus roots uptake of these metals by the plant were compared. The mean concentration of nickel in the leaves/canopy was found to be 13,980?±?10,780?mg?kg?1?dry mass, in the roots it was 2046?±?789?mg?kg?1 dry mass, and in the soil it was 1040?±?686?mg?kg?1?dry mass. This resulted in a mean concentration ratio in the leaves to soil of 13.44. The platinum mean concentration in the leaves was 0.22?±?0.15?mg?kg?1?dry mass, in the roots it was 0.14?±?0.04?mg?kg?1?dry mass, and in the soil it was 0.04?±?0.03?mg?kg?1?dry mass. This resulted in a mean concentration ratio in the leaves to soil of 5.5. Palladium was found to have a mean soil concentration of 0.07?±?0.045?mg?kg?1?dry mass. The mean concentrations in the roots and in the leaves were 0.18?±?0.07 dry mass and 0.71?±?0.52?mg?kg?1?dry mass, respectively. This gave a mean concentration ratio in the leaves to soil of 10.1 for palladium. Other elements that were found to have a mean concentration ratio in the leaves to soil of around 2.5 or above are sodium, potassium, magnesium, calcium, and sulfur. Berkheya coddii was found to be most efficient in accumulating nickel, palladium, and platinum from the soil. The results for the first time revealed that the plant may have the potential to uptake platinum and palladium; both metals are in the same group of the periodic table as nickel.  相似文献   

7.
The insecticide formulation, dicofol (18.5% EC) was evaluated for its toxic potential in developing chick embryo. Fertilized eggs of Gallus domesticus on 4th day of incubation were immersed in aqueous emulsions of dicofol at concentrations of 250?mg?L?1, 500?mg?L?1, and 1000?mg?L?1 for 60?min at 37°C. These concentrations were corresponding to those used in plant protection practice (500?mg?L?1). Two control groups of eggs were used: one group was immersed in distilled water (vehicle) and the second group was kept as untreated to study background toxicity. On embryonic day 7; recovered embryos were evaluated for mortality rate, wet body weight, gross morphological malformations, and some biochemical changes. The result revealed that administration of dicofol did not result in significant changes in wet body weight of embryo but the survival rate of dicofol treated embryos were markedly reduced as compared with controls. Among the survivors, the number of malformations was exhibited by dicofol treated embryos in dose-dependent manner. Among biochemical changes, only total protein content of embryo significantly (p?≤?0.05) reduced to 500?mg?L?1 and 1000?mg?L?1. Among enzymes, alkaline phosphatase and glutamate pyruvate transaminase activities were affected, which showed significant elevations.  相似文献   

8.
A study on the toxicokinetic behavior, metabolism of chlorpropham, and its effect on cytochrome P450 from liver microsomes was carried out in albino rats after a single and consecutive oral administration at 500?mg?kg?1 body weight for 10 and 20 days. Chlorpropham was detected in the blood at 0.08?h (11.43?±?1.72?µg?mL?1) reaching a maximum concentration at 2?h (30.90?±?2.55?µg?mL?1) and a minimum at 48?h (1.95?±?0.20?µg?mL?1) after a single oral administration of 500?mg?kg?1. The absorption rate constant (K a) was 0.66?±?0.48?h?1. The Vd area (18.01?±?2.78?L?kg?1) and t 1/2 β (12.23?±?1.96?h) values suggested a wide distribution and long persistence of the compound in the body, respectively. The higher ClR (0.82?±?0.00?L?kg?1?h?1) compared to ClH (0.18?±?0.02?L?kg?1?h?1) value indicated that a major portion of chlorpropham was excreted through the urine (30%) compared to the faeces (2.81%). Chlorpropham residue was detected in all tissues of rat at 0.25?h while its metabolite, meta-chloroaniline was detected in liver, kidney, heart, lung, and spleen tissue at 0.25?h. Meta-chloroaniline was not detected in skeletal muscle, brain, fat, and stomach tissue at any time of the observation period. Maximum concentrations of chlorpropham and meta-chloroaniline were detected at 2?h (except in the spleen), and minimum concentrations of chlorpropham at 24 (heart, lung, spleen, skeletal muscle, and stomach) and 48?h (liver, kidney, brain, and fat tissue) respectively; and meta-chloroaniline at 24?h (except heart and spleen). The tissue half-life of chlorpropham in rat varied from 3.80 to 11.60?h. Repeated oral administration of chlorpropham at 500?mg?kg?1 for 10 and 20 days caused an induction of the liver microsomal pellet of rat.  相似文献   

9.
A micro-scale algal growth inhibition (μ-AGI) test using a common micro-plate based fluorometric detection was used to demonstrate the effects of humic substances (HSs) on the toxicity of tetrabromobisphenol A (TBBPA) and its oxidative decomposition products 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,5-dibromohydroquinone (2,5-DBHQ), 2,6-dibromobenzoquinone (2,6-DBBQ), and 2,6-dibromophenol (2,6-DBP) to Pseudokirchneriella subcapitata. The EC50 values were: EC50(TBBPA) = 7 mg L?1, EC50(2,5-DBHQ) = 7 mg L?1, EC50(2,5-DBBQ) = 19 mg L?1, EC50(2,6-DBP) = 49 mg L?1, and EC50(2,6-DBBQ) = 13 mg L?1. The toxicity of the chemicals was slightly lower in the presence of HA. The toxicity of TBBPA decomposed by a biomimetic catalytic system consisting of iron (III) 5,10,15,20-tetrakis (p-sulfonatophenyl) porphyrin (Fe(III)-TPPS) and KHSO5 was also evaluated using P. subcapitata and Chlamydomonas reinhardtii.  相似文献   

10.
This article aims to determine the significant differences of the seasonal changes of pH, chemical oxygen demand (COD), biological oxygen demand (BOD), and total suspended solids (TSS) parameters in a wastewater stabilization pond. The variation of these parameters followed the seasonal pattern of temperature. The mean seasonal pH of the influent wastewater ranged between 7.8 (in spring) and 7.9 (in summer), while in the final effluents it was between 7.9 (in winter) and 8.3 (in summer). The mean seasonal COD of the influent wastewater ranged between 650?mg?L?1 in spring and 600?mg?L?1 in autumn, whereas in the effluents it was between 150?mg?L?1 in autumn and 270?mg?L?1 in spring. The mean seasonal BOD5 of the influent wastewater ranged between 360?mg?L?1 in autumn and 390?mg?L?1 in winter, whereas in the effluents it was between 66?mg?L?1 in summer and 130?mg?L?1 in winter. The results showed that the percent removals of COD, BOD5 and TSS from final effluents were maximum in summer for COD and BOD5 (76%), summer (83%) and for TSS in winter (78%), respectively. Data analysis showed that there were significant differences between parameters of pH, COD, BOD5 and TSS at four different seasons (p?相似文献   

11.
Physicochemical analyses and cyanobacterial diversity of Ramgarh Lake water were performed at five sampling sites during winter, summer, and monsoon seasons. Higher load of solids, carbon, and nutrients were persistent throughout the analysis that indicates the conversion of lake from oligotrophic to eutrophic nature. High nutrients load enhanced cyanobacterial biomass, while low nutrients load produced relatively less biomass. The physicochemical parameters of water samples revealed minimum 2.9 mg L?1 dissolved oxygen (DO) at site-1 during summer, while maximum (5.6 mg L?1) at site-4 in monsoon season. Maximum biochemical oxygen demand (BOD) (40 mg L?1) and chemical oxygen demand (COD) (126 mg L?1) were recorded at site-1 during summer, whereas minimum BOD (18 mg L?1) and COD (52 mg L?1) were evident at site-3 in monsoon season. Minimum concentration of nitrate (0.72 mg L?1) was recorded at site-3 in summer, whereas maximum 2.7 mg L?1 was present at site-5 in winter season. The phosphate concentration was maximum (0.52 mg L?1) at site-5 in summer, and minimum (0.18 mg L?1) was observed at site-4 in monsoon season. Cyanobacterial diversity was higher during all the seasons, and dominated by the species of Microcystis at all the five sampling sites.  相似文献   

12.
The mosquito larvicidal activities of different solvent extracts (chloroform, ethyl acetate, and methanol) from the leaves of Coccinia indica were studied. Among the extracts tested, the methanol extract showed the highest larvicidal activity against early fourth instar larvae of Culex quinquefasciatus (LC50?=?142?mg?L?1), Aedes aegypti (LC50?=?158?mg?L?1) and Anopheles stephensi (LC50?=?161?mg?L?1) after 24?h of exposure period. The lowest larval mortality was observed with the ethyl acetate extract with the LC50 values of 927, 872, and 730?mg?L?1 against Cx. quinquefasciatus, Ae. aegypti, and An. stephensi, respectively. The chloroform extract showed the moderate larvicidal activity against the mosquito species tested with the LC50 values from 446 to 546?mg?L?1. A new triterpene was isolated from the methanol extract using bio-assay guided separation and identified as an oleanolic acid derivative by NMR, IR and mass spectral studies. The compound showed prominent larvicidal activity against Cx. quinquefasciatus, Ae. aegypti and An. stephensi with the LC50 values of 5.6, 5.0, and 4.8?mg?L?1, respectively. The results of the present investigation offer an opportunity for developing alternatives to rather expensive and environmentally hazardous organic insecticides.  相似文献   

13.
The concentrations of lead and copper in sclerotium of the mushroom Pleurotus tuber-regium widely consumed in Southeastern Nigeria were determined. The specimens purchased from different markets were mineralized with H2SO4 and H2O2 and analyzed using flame atomic absorption spectrophotometer. The concentrations of Pb ranged from 0.2?±?0.1?mg?kg?1 to 0.8?±?0.5?mg?kg?1 with approximately 91% of the results being below 1?mg?kg?1. The concentrations of Cu ranged from 0.5?±?0.2?mg?kg?1 to 1.2?±?0.6?mg?kg?1 with 78% of the results below 1?mg?kg?1. The results were compared with the literature and levels set by regulatory authorities, with the conclusion that the consumption of sclerotium does not pose a toxicological risk. The low Pb content of the studied products would contribute to only about 1% of the provisional tolerable weekly intake of Pb. The Cu contents would contribute to nutritional intake of the metal in the general population. It is recommended that the outer layers of the sclerotia be properly scrapped before use to reduce metal contamination from exogenous sources.  相似文献   

14.
Accumulation of metals by aquatic organisms is mostly affected by other biological components in environments. In this study, cadmium (Cd) accumulation in green algae, Cladophora glomerata (L.) Kutz., exposed to 0.1 and 1.0 mg L?1 of Cd for 15 and 30 days was examined in laboratory conditions in the presence of Nile tilapia Oreochromis niloticus (L.). The green algae C. glomerata accumulated Cd concentrations as 690 ± 70 and 3430 ± 470 mg kg?1 on day 15, and 1130 ± 180 and 6830 ± 1540 mg kg?1 on day 30. There were significant increases (p < 0.05) in metal accumulation by green algae as the exposure time and metal concentration increased. The results also indicated that the presence of Nile tilapia in the medium led to a significant Cd accumulation in the green algae compared to control (p < 0.05).  相似文献   

15.
Catecholamines and their metabolites affect children's nervous system. Dopamine is an important neurotransmitter in the brain. In the routine analysis for diagnostics of diseases, the dopamine metabolite homovanillic acid (HVA) is determined. Mercury is a neurotoxic agent and can cause different undesirable effects on the brain. In the present work a putative correlation between HVA, the main metabolite of dopamine, and mercury in urine of healthy and autistic children was studied. The level of HVA was higher in the urine of autistic children (14.5 ± 8.3 mg L?1) compared to generally healthy children (4.4 ± 0.5 mg L?1). The level of mercury in the urine of autistic children was lower (0.36 ± 0.24 µg L?1) than in the urine of healthy children (2.1 ± 1.0 µg L?1) showing that there is no correlation between HVA and mercury.  相似文献   

16.
The aim of the study was to estimate Zn phytoextraction and changes in biomass of S?×?rubens growing in modified Knop's solution with different levels of Zn addition (0.5, 1.0, 2.5 and 5.0?mM). Obtained results were correlated with secretion of selected low-molecular-weight organic acids (LMWOAs) in the rhizosphere, roots and leaves. An increase in Zn concentration in Knop's solution resulted in Zn accumulation in roots, shoots and leaves. The highest accumulation was observed for plants growing in 5?mM Zn, at concentration levels 4741.36?±?98.66, 1227.31?±?16.57 and 2241.65?±?34.90?mg?kg?1 DW in roots, shoots and leaves, respectively. The bioaccumulation factor and the translocation factor for plants growing in 0.5, 1.0 and 2.5?mM Zn clearly indicate that this Salix taxon is an effective Zn accumulator. The general reduction of Salix biomass with an increase in Zn concentration in the solution was observed. In the rhizosphere, the total LMWOA concentration was almost 0.93?µmol?kg?1 DM for control (Zn free) plants, while for 5.0?mM of Zn it was 4.9?µmol?kg?1 DM. Increasing concentrations of acids were observed in roots (1.34 for the control and 5.57?µmol?kg?1 DM for plants treated with 2.5?mM of Zn).  相似文献   

17.
The accumulation of lead (Pb) in tilapias Oreochromis niloticus, acclimatized in cement tanks, and fed once a day with pellets of commercial food with lead nitrate, was investigated by square wave anodic stripping voltammetry (SWV). The head (including head bones, proteins, and brain) was the main target of lead uptake by tilapias, with a small amount in muscle tissue. A high concentration of Pb was found in feces which indicated low absorption by the organism when fed with high Pb concentration. The protective effects of zinc (Zn) against the Pb poisoning, the accumulation of Pb in the heads of the fishes of 107.8?±?3.1?mg?kg?1 and in the viscera of 57.1?±?2.9?mg?kg?1 with consequent decrease of calcium (Ca) concentration, were observed. In spite of the experimental time of 16 months and higher Pb concentration in the dietary food of 320?mg?kg?1, no death of tilapias was observed due to the protective action of Zn.  相似文献   

18.
Metal contents of waste mobile phones represent a major environmental risk, especially considering the adoption of inappropriate management options in developing countries including open burning and disposal into surface water bodies. In this study the metal contents of mobile phone printed wiring board (PWB) samples were assessed. Sixty-two waste mobile phones of 15 brands were collected, dismantled, and their PWB samples were analyzed for Cu, Pb, Ag and Cd. The metal concentrations in the samples varied widely between and within brands. Among these metals, Cu and Pb were found to be at very high concentrations. The range (mean?±?SD) of Cu and Pb concentrations were 94.1–532?g?kg?1 (250?±?92.3?g?kg?1) and 7.0–46.2?g?kg?1 (20.1?±?8.4?g?kg?1), respectively. All Cu and Pb concentrations exceeded toxicity threshold limit concentration (TTLC) regulatory limits used in characterizing wastes as hazardous in the state of California, USA. The mean Cu and Pb concentrations exceeded the corresponding TTLC limits by factors of 100 and 20, respectively. The Ag and Cd concentrations were in the range 59.4–759?mg?kg?1 (mean 227?±?104?mg?kg?1) and ND – 15.6?mg?kg?1 (2.1?±?3.3?mg?kg?1), respectively.  相似文献   

19.
The study deals with the toxicological impact of cadmium nanoparticles (Cd NPs) on Bacillus subtilis as a model Gram-positive bacterium. Cadmium oxide (CdO) NPs (~22 nm) and cadmium sulfide (CdS) NPs (~3 nm) were used in this study. Both the NPs were found to inhibit the cell viability of B. subtilis when added to the culture at mid-log phase, the viable cell number declined with increasing concentration of Cd NPs. At mid-log phase, 15 mg L?1 CdO NPs inhibited growth by ~50%, whereas at 30 mg L?1 growth completely ceased. Under the same conditions, CdS NPs inhibited growth by ~50% at a concentration of 8 mg L?1, and at 20 mg L?1 growth was completely retarded. The cells changed their morphological features to a filamentous form with increasing Cd NPs exposure time, leading to associated with clumping. NPs treated cells when stained with 4′, 6-diamino-2-phenylindole, showed filamentous multinucleated bead structure, suggesting irregularities in cell division. Increasing intracellular oxidative stress due to Cd NPs exposure might be one of the reasons for the cell morphological changes and toxicity in B. subtilis.  相似文献   

20.
Studies were carried out to determine the toxicity of some selected pesticides on fresh water fish in a tropical environment. The uptake of the pesticides lindane, pentachlorophenol (PCP), and propoxur, which are frequently used by farmers and industrialists were studied in concrete ponds at the University of Cape Coast, in Ghana. The fishes used for the study were Oreochromis niloticus, Clarias gariepinus, and Chrysicthys nigrodigitatus, and were obtained from cultured ponds in the Cape Coast District and Mankessim in the Central Region and Weija Dam, in the Greater Accra region of Ghana. Single high lethal concentration (SD) or acute treatment and cumulative/chronic (or multiple minor) lethal concentration (CD) treatment were employed in administering the pesticides to the fishes via water. Gas chromatograph (GC) Electron Capture Detector (ECD) analysis was done on the dead fishes to see the extent of ingestion. The LC50 values obtained for lindane on the three fish samples were as follows: Chrysicthys?–?0.38?mg?L?1; Oreochromis?–?0.42?mg?L?1, and Clarias?–?1.2?mg?L?1. Mortalities occurred in fish within 3–5 days of application. For the PCP on Chrysicthys, Oreochromis, and Clarias species the LC50 values were 0.42, 0.32 and 0.64?mg?L?1, respectively for over a 2–3 day period. For a three-time influx period of propoxur the LC50 for Chrysicthys, Oreochromis, and Clarias, were 22.0, 30.40, and 45.04 (all in mg?L?1), respectively. The results obtained indicated that the pesticides had adverse effects on the general growth and reproduction of fishes. Gonadosomatic indices also showed that the pesticides affected the development of the body, the gonads, and their reproduction.  相似文献   

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