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1.
The environmental behavior, movement, distribution, persistence, and runoff by rainfall of the pesticides acetochlor, atrazine, chlorpyrifos, and propisochlor were studied under field conditions during a five-month period at normal weather conditions. The pesticide concentrations in soil depths of 0-5 and 5-20 cm, and in sediment and runoff water samples (collected from an artificial reservoir built in the lower part of the experimental plot) were measured every second week and following every runoff event. The contamination of a stream running across the lowest part of the plot was also monitored. The weather conditions were also recorded at the experimental site. The pesticide residues were quantified by a capillary gas chromatograph equipped with a nitrogen phosphorus selective detector (GC-NPD). There was a consistent decrease in pesticide residues in the 0-5 cm soil layer with time after spaying. At 140 days after treatment only atrazine and chlorpyrifos were present; acetochlor and propisochlor were not detected in this soil layer. Atrazine and chlorpyrifos in the soil at a depth of 5-20 cm were detectable during the whole experimental interval, whereas acetochlor and propisochlor concentrations were below the limit of detection. Pesticide losses by the surface runoff process and the contamination of the stream were closely related to the time of rainfall elapsed after treatment and amount of rain at the experimental plots. Losses were primarily dependent on surface rainfall volume and intensity. The maximum detected residues of atrazine and acetochlor in stream water were 1 order of magnitude higher than the maximum residue limit specified by the European Union (EU) for environmental and drinking water (0.1 microg/L for individual compounds and 0.5 microg/L for total pesticides). Chlorpyrifos and propisochlor were not detected in this matrix.  相似文献   

2.
Organophosphorus pesticide residues in Mexican commercial pasteurized milk   总被引:4,自引:0,他引:4  
A study was conducted to measure residues of 13 organophosphorus (OP) pesticides, widely used as dairy cattle ectoparasiticides or in crops used for animal feed, in homogenized and pasteurized Mexican milk samples. Four different milk brands with high distribution were collected biweekly during a 12 month period (n = 96) in supermarkets. OP pesticide residues were measured by gas chromatography with a flame photometric detector. Approximately 39.6% of the samples contained detectable levels of OP pesticide residues. Eight samples contained residues exceeding established maximum residue limits (MRL), and the OP pesticides present in these samples were dichlorvos (five samples), phorate, chlorpyrifos, and chlorfenvinphos (one sample, respectively). Average residues of 13 OP pesticides measured were below established MRLs ranging between 0.0051 and 0.0203 ppm.  相似文献   

3.
The use of vegetated wetlands for accelerating pesticide removal from agricultural runoff is gaining acceptance as a best management practice. In this study, the dissipation of five cotton pesticides – endosulfan, chlorpyrifos, aldicarb, prometryn and diuron – was quantified in cotton field runoff water contained in glasshouse columns, under light or dark conditions. Two water samples sourced from large, non-vegetated storage dams were compared with two other water samples obtained from vegetated wetlands receiving runoff from cotton fields. All pesticides studied except chlorpyrifos dissipated significantly faster from the storage dam samples than the vegetated wetland samples. Suggested reasons include a greater number of pesticide-degrading microorganisms in the storage dam waters and/or the presence of more organic matter in the wetland samples, limiting contaminant volatilisation and hydrolysis. Exposure to light significantly reduced the rate of endosulfan removal, whereas light increased the rate of chlorpyrifos removal. Half-lives are presented for each pesticide where appropriate.  相似文献   

4.
The concentrations of 9 chlorinated pesticides in the water sources and tap waters of Istanbul, Turkey, were determined by gas chromatographic methods following the enrichment through adsorption and elution techniques. The observed organochlorine pesticides were α- and γ-HCH and aldrin which had been banned from use. The contents of α- and γ-HCH in raw waters were in the range of 0.34–1.7 ppb and not detected-0.077 ppb, respectively. Aldrin was observed at the concentration of 0.03 ppb in some samples. The residue levels of organochlorine pesticides in drinking water supplies of Istanbul were found significantly under the maximum permissible levels of standards. The effectiveness of potable water treatment processes and the importance of maintenance and back- washing of sand filters in pesticide removal were observed. Improper and delayed back-washings of filters caused an increase in the pesticide residues in the distributed water. In older water distribution lines, higher concentrations of some organochlorines were also observed.  相似文献   

5.
Effect of pesticide residues on the aromatic composition of red wines.   总被引:1,自引:0,他引:1  
The influence of pesticide residues on the aromatic composition (major and minor volatiles) of red wines made from Vitis vinifera (Monastrell var.) was studied by comparing the concentration of aromas in wines made from grapes subjected (or not) to phytosanitary treatment with chlorpyrifos, fenarimol, mancozeb, metalaxyl, penconazole, and vinclozolin, according to the agricultural practice of the area. The analytical determination of the major volatiles was made by gas chromatography using a flame ionization detector, while the minor volatiles were determined by adsorption-thermal desorption gas chromatography using a mass selective detector. There were significant differences between the ethyl acetate, methanol, isobutanol, and diethylacetal levels of the control wine and that containing chlorpyrifos residues, although only the ethyl acetate exceeded the olfactory threshold. With regard to the minor volatiles, significant differences were detected in the concentrations of some esters, aldehydes, and acids. However, only isoamyl acetate exceeded the olfactory threshold in wines containing residues of chlorpyrifos, fenarimol, and vinclozolin.  相似文献   

6.
Pesticide residues in grapes, wine, and their processing products   总被引:10,自引:0,他引:10  
In this review the results obtained in the 1990s from research on the behavior of pesticide residues on grapes, from treatment to harvest, and their fate in drying, wine-making, and alcoholic beverage processing are reported. The fungicide residues on grapes (cyproconazole, hexaconazole, kresoxim-methyl, myclobutanil, penconazole, tetraconazole, and triadimenol), the application rates of which were of a few tens of grams per hectare, were very low after treatment and were not detectable at harvest. Pyrimethanil residues were constant up to harvest, whereas fluazinam, cyprodinil, mepanipyrim, azoxystrobin, and fludioxonil showed different disappearance rates (t(1/2) = 4.3, 12, 12.8, 15.2, and 24 days, respectively). The decay rate of the organophosphorus insecticides was very fast with t(1/2) ranging between 0.97 and 3.84 days. The drying process determined a fruit concentration of 4 times. Despite this, the residue levels of benalaxyl, phosalone, metalaxyl, and procymidone on sun-dried grapes equalled those on the fresh grape, whereas they were higher for iprodione (1.6 times) and lower for vinclozolin and dimethoate (one-third and one-fifth, respectively). In the oven-drying process, benalaxyl, metalaxyl, and vinclozolin showed the same residue value in the fresh and dried fruit, whereas iprodione and procymidone resides were lower in raisins than in the fresh fruit. The wine-making process begins with the pressing of grapes. From this moment onward, because the pesticide on the grape surface comes into contact with the must, it is in a biphasic system, made up of a liquid phase (the must) and a solid phase (cake and lees), and will be apportioned between the two phases. The new fungicides have shown no effect on alcoholic or malolactic fermentation. In some cases the presence of pesticides has also stimulated the yeasts, especially Kloeckera apiculata, to produce more alcohol. After fermentation, pesticide residues in wine were always smaller than those on the grapes and in the must, except for those pesticides that did not have a preferential partition between liquid and solid phase (azoxystrobin, dimethoate, and pyrimethanil) and were present in wine at the same concentration as on the grapes. In some cases (mepanipyrim, fluazinam, and chlorpyrifos) no detectable residues were found in the wines at the end of fermentation. From a comparison of residues in wine obtained by vinification with and without skins, it can be seen that their values were generally not different. Among the clarifying substances commonly used in wine (bentonite, charcoal, gelatin, polyvinylpolypyrrolidone, potassium caseinate, and colloidal silicon dioxide), charcoal allowed the complete elimination of most pesticides, especially at low levels, whereas the other clarifying substances were ineffective. Wine and its byproducts (cake and lees) are used in the industry to produce alcohol and alcoholic beverages. Fenthion, quinalphos, and vinclozolin pass into the distillate from the lees only if present at very high concentrations, but with a very low transfer percantage (2, 1, and 0.1%, respectively). No residue passed from the cake into the distillate, whereas fenthion and vinclozolin pass from the wine, but only at low transfer percentages (13 and 5%, respectively).  相似文献   

7.
采用气相色谱法(GC-NPD,ECD)测定毒死蜱和氰戊菊酯残留量,研究了菠菜(Spinacia oleracea L.)和不结球白菜(Brassica campestris L. ssp. Chinensis Makino var. communis Tsen et Lee)中毒死蜱、氰戊菊酯的残留动态。结果表明,菠菜中毒死蜱残留量、不结球白菜中毒死蜱和氰戊菊酯残留量存在着明显的基因型差异。同一不结球白菜基因型,毒死蜱和氰戊菊酯的残留量达到《GB 2763—2005食品中农药最大残留限量》中规定的叶类蔬菜农药最大残留限量所需要的时间存在明显差异,且毒死蜱达到最大残留限量所需要的时间比氰戊菊酯长,因此在选择低农药残留基因型时,应首先考虑农药残留时间长、最大农药残留限量低的农药品种。菠菜品种sp0723、卡尔以及不结球白菜品种矮抗青、无锡605和青选3号属于低农药残留的基因型,在生产上推广应用有利于提高叶类蔬菜的食用安全水平。  相似文献   

8.
茶树油清除豇豆农药残留的效果   总被引:1,自引:0,他引:1  
为研究茶树油清除果蔬农药残留的效果,该试验选取豇豆为供试材料,以不同浓度的茶树油和水溶性茶树油等清洗处理,利用气相色谱和气相色谱-质谱联用检测豇豆内有机磷类、拟除虫菊酯类和氨基甲酸酯类的农药残留量,计算农药清除率。供试7种农药中,水胺硫磷、马拉硫磷、氧乐果、三唑磷、毒死蜱、氯氰菊酯和速灭威在豇豆中的初始浓度分别为:20.395、1.690、6.524、10.719、0.160、12.104和23.057mg/kg。茶树油处理后检测结果表明,茶树油具有清除残留在豇豆中农药的能力,清除效果随茶树油浓度增加而增强;清除有机磷类农药效果较拟除虫菊酯类和氨基甲酸酯类农药明显。茶树油比去离子水、市售果蔬农残清洗剂清除农药残留效果显著,同时,相同浓度的水溶性茶树油比相应茶树油清除农药残留能力强。0.8%水溶性茶树油清除效果最佳,清除率分别为水胺硫磷80.48%,马拉硫磷94.54%,三唑磷82.79%,毒死蜱84.58%,氧乐果72.20%,氯氰菊酯80.51%,速灭威72.21%。通过研究结果可知,茶树油可作为有开发前景的果蔬清除剂。  相似文献   

9.
Previously isolated bacterial strains for chlorpyrifos and fenamiphos degradation were used to examine their potential as bioremedial agents in soils and water containing pesticide residues. Both, chlorpyrifos-degrading Enterobacter sp and fenamiphos-degrading consortium rapidly degraded pesticides when inoculated into natural and sterile water and soils. Degradation rate was slower in lower pH soils in comparison with natural and alkaline soils. Soil organic matter had no impact on pesticide degrading ability of isolates. Soil moisture <40% of maximum water-holding capacity slowed down degradation rate. The bacterial isolates were able to rapidly degrade fenamiphos and chlorpyrifos between 15 and 35 °C but their degradation ability was sharply reduced at 5 and 50 °C. Both groups of bacterial systems were also able to remove a range of pesticide degradation. An inoculum density of 104 cells g−1 of soil was required for initiating rapid growth and degradation. Ageing of pesticide in soils prior to inoculation produced contrasting results. Ageing of fenamiphos had no impact on subsequent degradation by the inoculated consortium. However, degradation of chlorpyrifos by Enterobacter sp after aging resulted in persistence of ∼10% of pesticide in soil matrix. Higher Koc value of chlorpyrifos may have resulted in a lack of bioavailability of a smaller percentage of chlorpyrifos to degrading bacteria. Overall, this paper confirms bioremedial potential of a fenamiphos degrading consortium and a chlorpyrifos degrading bacterium under different soil and water characteristics.  相似文献   

10.
为研究茶树油清除果蔬农药残留的效果,该试验选取豇豆为供试材料,以不同浓度的茶树油和水溶性茶树油等清洗处理,利用气相色谱和气相色谱-质谱联用检测豇豆内有机磷类、拟除虫菊酯类和氨基甲酸酯类的农药残留量,计算农药清除率。供试7种农药中,水胺硫磷、马拉硫磷、氧乐果、三唑磷、毒死蜱、氯氰菊酯和速灭威在豇豆中的初始浓度分别为:20.395、1.690、6.524、10.719、0.160、12.104和23.057 mg/kg。茶树油处理后检测结果表明,茶树油具有清除残留在豇豆中农药的能力,清除效果随茶树油浓度增加而增强;清除有机磷类农药效果较拟除虫菊酯类和氨基甲酸酯类农药明显。茶树油比去离子水、市售果蔬农残清洗剂清除农药残留效果显著,同时,相同浓度的水溶性茶树油比相应茶树油清除农药残留能力强。0.8%水溶性茶树油清除效果最佳,清除率分别为水胺硫磷80.48%,马拉硫磷94.54%,三唑磷82.79%,毒死蜱84.58%,氧乐果72.20%,氯氰菊酯80.51%,速灭威72.21%。通过研究结果可知,茶树油可作为有开发前景的果蔬清除剂。  相似文献   

11.
The processing factors (pesticide concentration found in olive oil/pesticide concentration found in olives) of azinphos methyl, chlorpyrifos, lambda-cyhalothrin, deltamethrin, diazinon, dimethoate, endosulfan, and fenthion were determined in olive oil production process in various laboratory-scale olive oil extractions based on three- or two-phase centrifugation systems in comparison with samples collected during olive oil extractions in conventional olive mills located at different olive oil production areas in Greece. Pesticide analyses were performed using a multiresidue method developed in our laboratory for the determination of different insecticides and herbicides in olive oil by solid-phase extraction techniques coupled to gas chromatography detection (electron capture detection and nitrogen phosphorus detection), optimized, and validated for olive fruits sample preparation. Processing factors were found to vary among the different pesticides studied. Water addition in the oil extraction procedure (as in a three-phase centrifugation system) was found to decrease the processing factors of dimethoate, alpha-endosulfan, diazinon, and chlorpyrifos, whereas those of fenthion, azinphos methyl, beta-endosulfan, lambda-cyhalothrin, and deltamethrin residues were not affected. The water content of olives processed was found to proportionally affect pesticide processing factors. Fenthion sulfoxide and endosulfan sulfate were the major metabolites of fenthion and endosulfan, respectively, that were detected in laboratory-produced olive oils, but only the concentration of fenthion sulfoxide was found to increase with the increase of water addition in the olive oil extraction process.  相似文献   

12.
13.
The occurrence of chlorpyrifos, diazinon, pyrethroids, and fipronil was investigated in two watersheds along the southern California coast. Paired surface water and sediment samples were collected under dry and wet (after significant rain events) weather conditions. Insecticide concentrations in water and sediment were higher following rain events than during the dry season. Chlorpyrifos was the most frequently detected compound (>88%). Pyrethroids were detected in 74 and 100% of the water and sediment samples, respectively, with bifenthrin detected most frequently. Trans-permethrin was detected at the highest concentration followed by bifenthrin. Bifenthrin and trans-permethrin water concentrations were significantly correlated (P < 0.01) with the suspended solid level, suggesting transport facilitated by suspended particles. In 80% of the wet season samples with 100% of Ceriodaphnia dubia mortality, chlorpyrifos concentrations were >100 ng L(-1). Sediment pyrethroid levels (0.5-1100 ng g(-1)) were frequently higher than the respective Hyalella azteca LC(50) values, with bifenthrin as the primary contributor of H. azteca toxicity.  相似文献   

14.
The influence of the different steps involved in the wine-making process on the disappearance of chlorpyrifos, fenarimol, metalaxyl, penconazole, and vinclozolin in red wines elaborated by carbonic maceration of Monastrell grapes was studied. The initial levels of the residues in grapes ranged from 0.28 mg/kg (penconazole) to 1 mg/kg (chlorpyrifos). Ten days after the beginning of maceration, the compound that had decreased least was chlorpyrifos (83% of initial value remaining), whereas metalaxyl, the least persistent of the residues, had decreased to 49% of its initial value. In the free-run juice, on the other hand, the highest percentage remaining corresponded to metalaxyl (10%) and the lowest to chlorpyrifos (0. 1%). After pressing, the percentages of initial values eliminated in pomace varied from 82.7% for chlorpyrifos to 17.7% for metalaxyl, whereas in the press juice the opposite was the case (37% metalaxyl and 2% chlorpyrifos remaining). In finished wine, there were residues of all the pesticides, with the exception of chlorpyrifos, metalaxyl (21%) being the most persistent. The percentages eliminated in the lees varied from 1.5 to 2.5% of the initial value.  相似文献   

15.

Water samples collected in 1995 and 2007 from the Shinano and Agano rivers were examined to determine the types and concentrations of pesticides and their effects on tap water in typical rice production areas of Japan. Tap water originating from the Shinano River was also sampled in 2007, in Niigata City, Japan. Pesticides were present in the river and tap water throughout the year. Comparison of 13 pesticides common to both 1995 and 2007 series revealed that the frequency of individual pesticide occurrence and concentrations were decreasing. Riverine pesticides were classified into five groups according to the period of their appearance and changes in concentration. Pesticides were detected at the time of application to, and drainage from, paddy fields. Pesticide concentrations in tap water showed notable decline following rapid sand-filtration combined with granular activated carbon. The detection index (DI) for tap water and Shinano River water did not exceed a value of 1. Herbicides contributed most to the DI.

  相似文献   

16.
为探讨苹果果实中毒死蜱残留的品种间差异及套袋对其残留的影响作用,采用气相色谱法(GC-FPD),研究了不同品种苹果果实中毒死蜱的残留动态以及套袋对苹果果实不同部位中毒死蜱残留的影响。结果表明,毒死蜱在苹果果实中的残留量存在着明显的品种差异,其中红富士属于高农药残留的品种,而嘎拉、红将军和83-1-70-3则属于低农药残留的品种。毒死蜱在苹果果实不同部位中的残留量表现出明显差异,果皮是毒死蜱残留的主要部位,其次是全果,果肉中的残留最少。套袋明显减少了毒死蜱在苹果果实中的残留量,不论处理浓度和取样时间如何,套袋苹果果实中毒死蜱的残留量比不套袋至少减少1/3。  相似文献   

17.
为解决食品中毒死蜱残留检测过程中步骤繁琐,灵敏度低的问题,采用高富集因子的针式滤器固相微萃取结合高灵敏度的酶抑制-数字图像比色法对毒死蜱进行快速检测。该研究以石墨烯纳米片作为固相吸附剂装入针式滤器,随后通过注射器重复抽打针式滤器的方法实现样品中毒死蜱的富集。酪氨酸酶能够将邻氨基苯酚和氯化铁体系氧化为黄色,毒死蜱会抑制酪氨酸酶的活性,从而会间接影响邻氨基苯酚和氯化铁体系的显色,通过数字图像比色法实现毒死蜱的定量分析。结果表明:毒死蜱在0.005~0.1 mg/L范围内线性良好,R2>0.99。在矿泉水、茶水和果汁中的测定下限为0.005 mg/L。样品加标后的萃取率为86.6%~92.5%,相对标准偏差为3.2%~6.9%。该方法有助于开发农药的快速前处理和检测技术。  相似文献   

18.
The effect of a spray-tank adjuvant on the persistence, distribution, and degradation of two pesticides, chlorothalonil and chlorpyrifos, was studied in a commercial cranberry bog. Pesticides were applied according to label instructions to cranberry plants in paired plot studies. Dislodgeable foliar and whole fruit residues of both pesticides and several degradation products were assessed over a growing season. Residues were also assessed in soil samples collected at fruit harvest. Adjuvant increased both fruit and foliar residues but did not significantly alter the dissipation rate or metabolism of either pesticide. The dissipation of dislodgeable foliar chlorothalonil and chlorpyrifos residues followed first-order kinetics, with estimated half-lives of 12.7 and 3.5 d, respectively. All residue levels on harvested fruit were well below the current U.S. EPA tolerances for fresh cranberries. Chlorothalonil (58%) was the major residue in fruit at harvest (76 d post-chlorothalonil application), with 4-hydroxy-2,5,6-trichloroisophthalonitrile and 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene accounting for 26% and 6% of the total residues, respectively. Degradation products accounted for 88% of the total chlorothalonil residues in soil at fruit harvest. The products 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene, 1-carbamoyl-3-cyano-4-hydroxy-2,5,6-trichlorobenzene, 2,5,6-trichloro-4-methylthioisophthalonitrile, and 2,4,5-trichloroisophthalonitrile have not been previously identified in cranberry bog environments. Chlorpyrifos was detected in fruit at harvest (62 d post-chlorpyrifos application), but no metabolites were found. Chlorpyrifos-oxon and 3,5,6-trichloro-2-pyridinol, however, were detected in earlier fruit samples and in foliage and soil samples.  相似文献   

19.
为了解我国西北地区蔬菜水果和食用菌的质量安全情况及暴露风险,本试验从2018至2020年在我国甘肃省平凉市进行样品抽取,共测定2 435份蔬菜水果和食用菌样品中46种农药残留的含量.通过农药残留风险评估方法分析了 9类别蔬菜水果和食用菌中农药残留的分布和相关性,并对蔬菜和水果中农药残留情况进行了风险排序,以及暴露风险、...  相似文献   

20.
Low levels of pesticides and their metabolites/degradates occur in produce when pesticides are used in conventional or organic crop protection. Human dietary and nonoccupational urine biomonitoring studies may be confounded by preformed pesticide biomarkers in the diet. The extent of formation of putative urine biomarkers, including malathion specific (MMA, MDA; malathion mono- and diacids), organophosphorus generic (DMP, DMTP, DMDTP; dimethyl-, dimethylthio-, and dimethydithiophosphate), pyrethroid generic (3-PBA; 3-phenoxybenzoic acid), and captan-specific metabolites (THPI; tetrahydrophthalimide), was measured in produce samples containing the parent pesticide. Every produce sample of 19 types of fruits and vegetables contained biomarkers of potential human exposure. A total of 134 of 157 (85%) samples contained more molar equivalent biomarkers than parent pesticide. Malathion and fenpropathrin were sprayed (1 lb/A), and the time-dependent formation of pesticide biomarkers in strawberries was investigated under field conditions typical of commercial production in California. Malathion and fenpropathrin residues were always below established residue tolerances. Malathion, MMA, and MDA dissipated, while DMP, DMTP, and DMDTP increased, during a 20 day study period following the preharvest interval. The mole ratios of biomarkers/(malathion + malaoxon) were always greater than 1 and increased from day 4 to day 23 postapplication. Fenpropathrin and 3-PBA also dissipated in strawberries during each monitoring period. The mole ratios of 3-PBA/fenpropathrin were always less than 1 and decreased from day 4 to day 14. The absorption of pesticide biomarkers in produce and excretion in urine would falsely indicate consumer pesticide exposure if used to reconstruct dose for risk characterization.  相似文献   

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