ABSTRACT
Molecularly imprinted polymers for dimethoate recognition were synthesized by the precipitation polymerization technique using methyl methacrylate (MMA) as the functional monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. The morphology, adsorption and recognition properties were investigated by scanning electron microscopy (SEM), static adsorption test, and competitive adsorption test. To obtain the best selectivity and binding performance, the synthesis and adsorption conditions of MIPs were optimized through single factor experiments. Under the optimized conditions, the resultant polymers exhibited uniform size, satisfactory binding capacity and significant selectivity. Furthermore, the imprinted polymers were successfully applied as a specific solid-phase extractants combined with high performance liquid chromatography (HPLC) for determination of dimethoate residues in the cucumber samples. The average recoveries of three spiked samples ranged from 78.5% to 87.9% with the relative standard deviations (RSDs) less than 4.4% and the limit of detection (LOD) obtained for dimethoate as low as 2.3μg/mL.
ABSTRACT
Organ histopathology and changes in biochemical parameters in fish are good biomarkers of aquatic pollution. This study is an attempt to assess the effects of dimethoate, an organophosphate insecticide on the liver of common carp (C. carpio). Healthy individual fish were exposed to 0.40 mg l-1 (25% of 96 hr LC50) concentration of dimethoate, for short term (96 hr). Liver of the exposed fish exhibited alterations like disruption of regular arrangement of hepatocytes, congestion and rupture of vessels; hemorrhage, cytoplasmic vacuolization, pyknotic nuclei and necrosis. Biochemical parameters viz. total liver protein (p<0.001) and liver glycogen (p<0.001) registered a significant decrease and blood glucose (p<0.001) exhibited significant increase throughout exposure.
ABSTRACT
Temperature is a crucial determinant of biogeography, directly affecting the behavioral responses of the organisms. An acute static bioassay was conducted to evaluate the effect of temperature on dimethoate toxicity in a freshwater mussel Lamellidens marginalis. The mussel, were exposed for 96 hr at different concentrations of dimethoate (155.00, 160.00, 165.00, 170.00, 175.00, 180.00, 185.00, 190.00, 195.00, and 200.00 mgl-1) in the month of January when water temperature was 14.9±1.20C and at concentration 35.00, 37.00, 39.00, 41.00, 43.00, 45.00, 47.00, and 49.00 mgl-1 in the month of August when the water temperature was 28.0±0.50C. The LC50 values were calculated from the mortality data obtained (using EPA-Probit analysis version 1.5, statistical software). The 96 hr LC50 value recorded at higher temperature was 36.34mgl-1 and at low temperature was 163.59 mgl-1. The mussel exposed at higher temperature showed more sensitive behavioral responses like huge mucus secretion, sudden closure of shell valves, quick post-mortem changes and increased oxygen consumption in comparison to exposure at low temperature. Therefore, the increasing threat of global warming increases the risk of pesticide toxicity in the exposed organisms.
ABSTRACT
Pesticides are chemicals used for pest control in the agricultural fields. They finally reach the surrounding water bodies through surface runoff affecting the aquatic fauna. Dimethoate is frequently used organophosphate pesticide due to its high effectiveness and rapid breakdown into environmentally safe products. A 96 hr static acute toxicity test was carried out to determine the LC50 value of dimethoate, on the freshwater airbreathing catfish Heteropneustes fossilis (Bloch). The fish were exposed to 7 different concentrations of dimethoate (2.50, 2.75, 3.00, 3.25, 3.50, 3.75 and 4.00 mg l-1) for toxicity bioassay. Control (0.00 mg l-1) was also carried out. The data were subjected to Finney’s Probit analysis and processed with Trimmed Spearman-Karber statistical software. The LC50 values for dimethoate for 24, 48, 72 and 96 hr were 3.38, 3.23, 3.08 and 2.98 mg l-1, respectively. At higher concentration of dimethoate (3.25 mg l-1 and above) the fish showed uncoordinated behaviour such as erratic and jerky swimming, attempt to jump out of water, frequent surfacing and gulping of air, decrease in opercular movement and copious secretion of mucus all over the body.
ABSTRACT
Objective To study the effect of Rhubarb as a supplemental emergency treatment for acute omethoate Poisoning (AOMP). Methods 80 male SD rats were randomly divided into 4 groups: slight intoxication group, severe intosieation group, therapeutial group of Rhubarb after severe intoxication and normal control group. The intoxication experimental model (one slight group, two severe groups) were made by intragastrically given at different dose of Omethoate. The severe group was received Rhubarb treatment. Results The rats action in Rhubarb treated group was significantly better than that in control group, and the level of cholinesterase (ChE) and superoxide dismutase (SOD) in serum st different time were significantly higher than those in other two intoxication groups. (P<0. 05 or P <0.01).Conclusions Rhubarb might be good for AOMP as a supple mental emergency therapy.
ABSTRACT
A 40-years-old man had taken organophosphate (dimethoate) before one day and he was treated with gastric irrigation only in the private hospital for one day. But he was found dead after several hours from discharge. Bereaved families suspected medical mistakes and claimed autopsy. After autopsy, we concluded that he was died by respiratory failure on account of dimethoate intoxication. Generally symptoms of organophosphate poisoning appear immediately, but this case shows unusual course of intoxication. Here in, we reported a delayed death due to organophosphate intoxication with literature review.
Subject(s)
Humans , Autopsy , Dimethoate , Gastric Lavage , Hospitals, Private , Medical Errors , Organophosphate Poisoning , Respiratory InsufficiencyABSTRACT
Objective To evaluate the efficiency of different wash methods for removing organophosphorus pesticide residues from cucumber. Methods The cucumber samples were soaked with tap water, washed rice water, salt solution and detergent solution respectively for 2 to 15 minutes then organophosphorus pesticide residues in the soak water samples were determined with ultrasonic extraction and gas chromatography. Results Soaked in tap water for 2 to 5 minutes was the most effective and convenient way to remove methamidophos and dimethoate with the highest removing rate (about 70%). Conclusion Soaked with tap water for 2 to 5 minutes is more efficient for removing organophosphorus pesticide residues from vegetable.
ABSTRACT
Objective Micronucleus test(MNT) was used to evaluate the single and combined genotoxicity of dichlorvos(DDVP),dimethoate(DM) and malathion(Mal) in HepG2 cell line,and 2?2 factorial design was adopted to elucidate the combined genotoxic effects.Methods In cytotoxicity test,HepG2 cells were exposed to the three OPPs(DDCP,DM,Mal) for 4 h respectively,and the doses at which cell viability above 80% were selected for the MNT,DDVP:3.125-25 ?g/ml,DM:25-200 ?g/ml,Mal:50400 ?g/ml,the micronucleated cell(MNC) rates and the replicative index(RI) were calculated.The combined genotoxicity of them was investigated with their doses as follows:low dose(DDVP:3.125 ?g/ml,DM:25 ?g/ml,Mal:50 ?g/ml);high dose(DDVP:12.5 ?g/ml,DM:100 ?g/ml,Mal:200 ?g/ml).Results In MNT,after treatment of HepG2 cells with DDVP,DM or Mal alone for 4 h,the MNC rates were increased in a dose-response manner(DDVP:r=0.955,P