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771.
A study to understand the mobility and transport of heavy metals (HMs) from soil and soil amended with sewage sludge to maize plants was carried out. The total and ethylenediaminetetraaceticacid (EDTA)-extractable HMs in agricultural soil and untreated domestic sewage sludge samples, and the correlation between the total and extractable metals in soil and sewage sludge were carried out. Pot experiments were performed to study the transfer of HMs to maize grains, grown in soil (control) and in soil amended with sewage sludge (test samples). The total and extractable HMs in soil, sewage sludge, and maize grains were analysed by FAAS/ETAAS (flame atomic absorption spectrometer/electrothermal atomic absorption spectrometer) after digestion in microwave oven. Statistically significant correlations were obtained between the total contents of Cu, Cd, As and their respective extractable fractions in soil, while in domestic wastewater sludge (DWS) the better correlation was observed only for Ni and Cd. The edible part of maize plants (grains) from test samples presented high concentration of Zn, Pb, Ni, Cd, Cu, As, and Cr concentrations (80.7–85.6, 3.8–3.95, 2.35–2.5, 0.75–0.82, 3.21–3.29, 0.23–0.27, and 0.22–0.29?mg?kg?1, respectively). Good correlations were found between metals in exchangeable fractions of both soil and DWS and total metals in control and test samples of maize grains. The transfer factor of all HMs from DWS to maize grains was also determined.  相似文献   
772.
The fatty acid (FA) composition was determined in 14 species of marine macroalgae belonging to the Chlorophyta, Phaeophyta and Rhodophyta, which were collected from ?ile in the Black Sea and Kepez in the Dardanelles. Generally, polyunsaturated FAs and monounsaturated FAs were major components (50–77%). Total saturated FAs ranged from 22% to 50%, with 16?:?0 as the most abundant saturate (32–38%). Two samples of Cystoseira barbata collected from a different station had some differences from each other in their contents of 18?:?2n-6 and 18?:?3n-3 and in the 18?:?2n-6/20?:?4n-6 ratios. Green algal species had a significantly higher proportion of unsaturated FAs and a significantly lower proportion of saturated FAs than the red and brown algae. The amount of n-3 FAs was significantly higher in Ulva rigita, Chaetomorpha linum, Enteromorpha linza and Gracilaria verrucosa (8.88, 6.44, 5.31 and 5.24, respectively).  相似文献   
773.
In this study, residual concentrations of chlorpyrifos (CPF) were determined in feed (40) and fodder (25) samples collected from various locations of Tarai region of Uttarakhand. For extracting residues, liquid–liquid partition followed by alumina column clean up was used and the detection and quantification of residues was undertaken with the help of high-performance liquid chromatography using C18 column and diode array detector at 220?nm. Of the total 40 feed samples analyzed, 7 (17.5%) samples were found positive for CPF with the mean residual concentration of 0.058?µg?g?1; while out of 25 fodder samples, CPF residues were detected in a single (4%) sample with residual concentration of 0.39?µg?g?1. However, none of the feed or fodder samples contained CPF residues above the prescribed limit.  相似文献   
774.
Fly ash is the major coal combustion byproduct from thermal power plants. Considering its plant–nourishing constituents, its soil amendment in farmland is one of its promoted disposal methods. A substantial amount of heavy metals present in fly ash, which may leach out due to rainwater or irrigation water, may cause serious problem with long term use, especially to soil organisms. These metals may cause DNA damage through Reactive Oxygen Species (ROS) generation. In the present study, single cell gel electrophoresis [(SCGE) i.e., comet assay] was used to detect DNA damage in earthworm (Dichogaster curgensis) coelomocytes, following an in vitro exposure. Significant DNA damage was observed at the lowest concentration of fly ash leachate (6.25%) examined. DNA damage by all the tested concentrations (6.25%, 12.5%, 25%, 50%) differed significantly (p?<?0.001) from that of the negative control. Hence, long-term application of fly ash might prove harmful for earthworm populations.  相似文献   
775.
The effect of carbofuran, a carbamate pesticide, on the breeding performance of the freshwater fish Labeo rohita (Hamilton) has been investigated in the present study. Breeding of L. rohita was conducted after treatment with three sublethal concentrations, i.e. 0.06, 0.15 and 0.30 mg L?1 of carbofuran for 96 h. The present investigation showed that the number of total eggs and total amount of eggs (litre per kg body weight) decreased significantly (p < 0.01) at all concentrations of carbofuran in comparison to controls, while the reduction in fertilization percentage at all concentrations of carbofuran was not significantly different from controls. The reduction in hatching percentage, the expected number of hatchlings, and the expected number of hatched larvae were significantly (p < 0.01) different between treated and control groups at all carbofuran concentrations. No significant differences for the 96 h survivability of hatched larvae were reported at all concentrations of carbofuran.  相似文献   
776.
Adult respiratory distress syndrome (ARDS) is a clinical syndrome which occurs due to various direct or indirect noxious agents and pyhsical mechanisms. One of the etiological factors is ingested chemicals (e.g. paraquat, ethylene glycol). The organophosphorous (OP) insecticides are the most toxic and frequently encountered chemicals that produce poisoning in humans. Studies were undertaken to investigate whether OP insecticides may produce ARDS. Fifteen autopsy cases due to suicidal OP insecticide poisoning were investigated. Toxicological analyses were performed with a gas chromatography-nitrogen phosphorous detector (GC-NPD). Methamidophos, dimefox and dichlorvos were the detected OP. Lungs were examined macroscopically. Two cases showed features compatible with ARDS in which the only cause of death was OP poisoning. Due to the severity of ARDS it is important to assess insecticidal exposure in an attempt to enhance survival patterns following OP poisoning in patients in order to initiate therapy.  相似文献   
777.
We determined the normal levels of butyrylcholinesterase (BChE), carboxylesterase (CbE), and glutathione S-transferases (GST) activities in three South American toad species in order to establish reference values for field pesticide monitoring purposes. Interspecies variations in B-esterase and GST activities were examined according to body mass. In addition, comparative inhibition of BChE and CbE activities using malaoxon, and chemical reactivation of malaoxon-inhibited BChE activity using pyridine-2-aldoxime methochloride (2-PAM) were investigated. Bufo fernandezae had average activity values for BChE: 17.31 mmol min?1 ml?1; CbE: 621.49 nmol min?1 ml?1 and GST: 1.94 mmol min?1 ml?1 while B. arenarum enzymatic average activities were BChE: 9.51 mmol min?1 ml?1; CbE: 270.07 nmol min?1 ml?1, and GST: 1.59 mmol min?1 ml?1; finally Bufo schneideri had enzymatic mean values of BChE: 2.08 mmol min?1 ml?1; CbE: 301.95 nmol min?1 ml?1, and GST: 1.60 mmol min?1 ml?1. Moreover, we found an allometric relationship between plasma BChE and CbE activities and body size for the three toad species. We suggest that B. fernandezae would be the species with a higher tolerance capacity to organophosphorous insecticides compared to the other toad species, while B. schneideri may be the most vulnerable toad species to field pesticide exposure, although some other factors (e.g., brain AChE sensitivity or pesticide metabolism by phosphotriesterases) should be also taken into account. The malaoxon-inhibited BChE activity of the three toad species was reactivated in the presence of 2-PAM, and it is recommended as a specific and sensitive methodology in the assessment of field exposure to OP insecticides together to compare BChE activity levels between OP-exposed and nonexposed individuals.  相似文献   
778.
The effect of interaction of alcohol and kola nut on sodium pump activity was studied in Wistar rats. Thirty Wistar rats were divided into six groups of five rats per group. Control received a placebo (4 mL of distilled water). Groups 2–6 were treated for a period of 21 days with 10% (v/v) alcohol, 50 mg caffeine/kg, 50 mg kola nut/kg, or a combination of 10% (v/v) alcohol + 50 mg kola nut/kg, or 10% (v/v) alcohol + 50 mg caffeine/kg, respectively. One day after the final exposure, brains were harvested and several biochemical parameters examined including activities of total ATPase, ouabain-insensitive ATPase, ouabain sensitive ATPase (Na+–K+-ATPase) and levels of nonenzymatic breakdown of ATP and inorganic phosphate (Pi) released. Results showed that the essential enzyme of the brain responsible for neuronal function, Na+–K+-ATPase, was inhibited by alcohol–kola nut co-administration relative to control, resulting in a decreased ATP production, ion transport and action potential, leading to loss of neuronal activities.  相似文献   
779.
The effects of Cd at environmental concentrations (0–32 µg/L) on the green alga Parachlorella kessleri were investigated. At about 3 µg Cd/L, toxic effects of Cd are becoming evident, much lower than reported previously. At 8 µg/L and higher, pronounced adverse effects on growth, cell morphology, size, and physiological state are seen. Therefore, levels lower than 2 µg Cd/L should be employed to produce Cd-carrying algae for feeding experiments with organisms on the next trophic level, e.g. mussels, to avoid reduced food uptake. These findings also suggest that aquatic ecosystem conditions can be indirectly influenced via the impairment of the nutritional value of algae since they are the basic organisms of aquatic food chains.  相似文献   
780.
Effects of artemether administration on liver and selected biochemical parameters were evaluated. Eighty albino mice were divided into four equal groups. Group 1 was given water which served as control, while groups 2, 3, and 4 were given 1.2, 2.4, or 4.8 mg kg?1 body weight artemether intramuscularly for five consecutive days. On day 6 all mice were sacrificed by cervical dislocation and blood was collected for analysis of alanine and aspartate transaminases, alkaline phosphatase, copper, and total proteins. Liver tissues were prepared for histological studies. It was found that the serum alanine and aspartate transaminase and alkaline phosphatase activities were higher in groups treated with artemether compared to control. The serum concentrations of copper and total proteins were lower than control. The histological features of liver tissues after administration of artemether showed histopathological alterations. These findings showed that artemether administration may have reversible adverse effects on mouse hepatocytes.  相似文献   
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