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BACKGROUND: Greenhouse tomato production is intended exclusively for fresh consumption. Typical greenhouse conditions provide a conducive environment for the development of different fungi, principally late blight and grey mould, that can destroy plants and fruits. For this reason, different fungicides with different sites of action are used in integrated pest management strategies. Famoxadone, fenamidone, fenhexamid and iprodione (fig. 1 ) are fungicides of difference classes with different actions that could be used to control tomato pests. RESULTS: The QuEChERS method showed good recoveries, and the analytical method allowed good separation of the fungicides selected. Good results were obtained in terms of repeatability and intermediate precision, with a coefficient of variation of < 9.8%. The limits of determination and quantification of the method were far below the maximum residual levels (MRLs) set by the EU for these fungicides in tomatoes. The analysis of fungicide residues showed that cv. Shiren accounted for higher residue levels than cv. Caramba. The dissipation curves were similar in the two cultivars, indicating that the decrease in pesticides was not related to the tomato type. CONCLUSIONS: Care should be taken when using pesticides in greenhouse conditions, because degradation mainly affects fruit growth. The size of the tomato, in particular its surface/weight ratio, is very important for defining pesticide residues. All fungicides used showed residue levels below the MRLs at the preharvest interval. Copyright © 2011 Society of Chemical Industry 相似文献
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吡虫啉、苯醚甲环唑和百菌清在甘蓝中的消解及残留分布 总被引：1，自引：0，他引：1
为明确吡虫啉、苯醚甲环唑和百菌清在露地甘蓝中的消解动态及残留分布规律,在田间施用农药后,采用液相色谱-质谱联用仪和气相色谱仪,对不同时间甘蓝样品及甘蓝不同部位的农药残留量进行了分析。结果表明:3种农药在甘蓝中的消解动态均符合一级反应动力学模型,其中,吡虫啉消解最快,苯醚甲环唑次之,百菌清最慢,半衰期分别为1.35、2.28和2.47 d。最终残留试验结果显示:施药后7和14 d,吡虫啉、百菌清在甘蓝中的残留量均符合食品中农药残留限量要求,而苯醚甲环唑在施药后14 d的残留量仍高于最大残留限量值 (MRL)。3种农药在甘蓝不同部位中的残留量差异显著 (P<0.05),其中甘蓝内球叶中未检出或残留量较低,外球叶中初始残留量较低,1至5 d可降至MRL值以下,外叶中的残留量显著高于其他部位。该结果表明,采后处理甘蓝时若去除其外叶,可有效降低甘蓝中的农药残留量,提高质量安全水平。 相似文献
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为评估福建省主产区普通白菜中农药残留水平及对人体的膳食暴露风险,采用现有的标准检测方法,对在福建省主产区采集的88个普通白菜样品中的68种农药残留进行了检测分析,并对检出农药进行了短期和长期膳食暴露风险评估。结果显示：88个普通白菜样品中,共有68个样品检出了农药残留,总检出率为77.27%;共检出27种农药,其中杀虫剂18种,杀菌剂9种;检出2种及2种以上农药残留的样品占检出农药残留样品总量的83.82%,存在农药多残留现象。利用相关农药的毒理学数据——急性参考剂量(ARfD)和每日允许摄入量(ADI)、农药残留数据和普通白菜的膳食消费量数据,评估了所检出农药的短期和长期膳食暴露风险。其中,短期膳食暴露风险值(%ARfD)范围为0～90%,长期膳食暴露风险商贡献率(RQc%)范围为0～46%。研究表明,福建省主产区普通白菜中的农药残留水平较低,通过食用该地区生产的普通白菜对消费者的农药残留膳食暴露风险整体在可接受范围内。 相似文献
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Soil samples collected during 1975 and 1976 from United States Air Force installations in California, Georgia, Ohio, Oklahoma, Texas, and Utah were analyzed for organochlorine pesticide residues. Sigma DDT, chlordane, and dieldrin were the pesticides most commonly found. In 1975, sigma DDT residues were significantly higher in samples from residential areas than in samples from golf courses or areas free of pesticide application. Chlordane residues in 1975 were significantly higher in both residential and golf course areas than in areas where pesticides had not been used. No significant differences were found in 1976 in residue levels of any pesticide monitored among various land use areas. 相似文献
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我国小麦中农药残留及代谢研究进展 总被引：1，自引：0，他引：1
为全面了解小麦中农药残留量水平及代谢状况,合理评价小麦及其产品的质量安全和品质,综述了小麦中常用农药残留、代谢的研究现状及综合治理策略。有机磷类、有机氯类及其他一些常用农药在小麦及其产品中的残留水平较低,均未超过国家相关最大残留限量(MRL)标准;目前针对具有典型代谢产物的农药在小麦体内残留、代谢及转化规律的系统研究很少。提出了应进一步加强立法、建立高效的综合防治体系、继续实施小麦生产过程中农药残留监控、加强小麦流通领域的监督抽查力度等农药残留的综合治理策略,可为农药在小麦上的安全合理使用、提高小麦及其产品的质量安全及品质提供参考。 相似文献
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Organochlorine pesticide residues in various organisms from different aquatic ecosystems in Iran were investigated in spring 1974. DDT levels were high in fish taken from two rivers in southern Iran, whereas low levels were detected in samples obtained from a freshwater lake in the same area. Fish from two of the reservoirs supplying Tehran with potable water contained moderate levels of DDT. The low residue level in pike collected in the Bandar-Pahlavi Mordab in northwest Iran indicates that only a small amount of organochlorine pesticides used in this area enters the pelagic food chain. Sturgeon collected at different places in the Caspian Sea showed similar accumulations of DDT in the muscles and in the eggs. Polychlorinated biphenyls (PCBs) were detected only in samples of sediment from the drainage systems in Tehran. 相似文献
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关于JMPR植物源产品残留定义中含有代谢产物的农药在进行膳食风险评估时残留数据计算的介绍 总被引：3，自引：0，他引：3
联合国粮农组织和世界卫生组织农药残留联席会议(JMPR)将农药残留定义分为2类,即植物源产品残留定义和动物源产品残留定义;同时根据使用目的不同,又将农药残留定义分为风险评估残留定义和监测残留定义。JMPR在植物源产品农药风险评估残留定义中包含的代谢产物类型主要分4种情况:一是残留定义包含母体和代谢产物,代谢产物是农药;二是残留定义包含母体和代谢产物,代谢产物不是农药;三是残留物定义只包括代谢产物,且代谢产物不是农药;四是二硫代氨基甲酸酯类农药。本文综述了JMPR关于植物源产品残留定义中含有代谢产物的农药进行农药残留膳食风险评估时残留数据的计算,旨在为我国制定农药最大残留限量标准进行农药残留膳食风险评估时提供借鉴和参考。 相似文献
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Maria Joo A. Magalhes Júlia R. Ferreira Lúcia Frutuoso Antnio A. Taínha 《Pest management science》1989,27(1):23-31
The influence of surface of exposure of brassicas to insecticide sprays has been assessed in two experiments conducted in small plots where endosulfan, parathion, trichlorfon and pirimicarb were applied to a flowering brassica, broccoli (Brassica oleracea L. var italica Plenck) and to a leafy brassica (Brassica oleracea L. var. tronchuda Bailey). The differences of surface exposure resulted in much higher deposits and subsequent residue levels in broccoli. The results stress the need to evaluate residue data on groups of brassicas of different surfaces of exposure to pesticide spray when granting registration petitions for brassicas in general in order to establish pre-harvest intervals. 相似文献
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A 'step-by-step' method was used to develop a simplified procedure for calculating pesticide residue levels on fruit at harvest by considering the application of the compound and the relevant routes of loss. The model is applicable to cases where the most important exposure route is by direct spray to the canopy of the crop and where uptake into the plant by the roots can be disregarded. The exposure dose is calculated by considering the proportion of total crop cover represented by the fruits. The loss processes considered are photodegradation, uptake, volatilization and washoff.The outputs of the model were compared with measured residues of pesticides on pear. Analysis of the model fit demonstrates that the model predicted the measured data with a good level of accuracy for four of seven investigated pesticides. The predicted/observed quotients are close to 1, as is the modelling efficiency, and there are no great differences between the predicted and observed values. Taking into account the extreme simplicity of the model and the complexity of the environmental processes considered, these results encourage further research into the modelling of residue behaviour in food commodities.The objectives of this work were to produce a tool to predict pesticide residues in products of plant origin, to complement monitoring of pesticide levels and to be useful in evaluating the effect of government policies on food safety. All predicted values were below the maximum levels fixed for pesticide residues in pear, as amended in Council Directives 86/362/EEC and 90/642/EEC. Copyright (c) 2008 Society of Chemical Industry. 相似文献
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Ioannis Chatzicharisis Thomas Thomidis Constantinos Tsipouridis Efthimia Mourkidou-Papadopoulou Zisis Vryzas 《Phytoparasitica》2012,40(4):311-317
One of the key features of the new cultural systems is the control of harmful agents with environment-friendly methods. In this study, the residue levels of chlorothalonil, iprodione, bupirimate, pirimicarb, chlorpyrifos and fenoxycarb in different peach??nectarine cultivars were investigated. It was found that, with the exception of chlorpyrifos, the residue levels of all pesticides were lower than the Maximum Residues Limits (MRLs) in all peach??nectarine cultivars used. The detected levels of chlorpyrifos were higher than the MRLs in the cultivar ??Maria Bianca?? 7?days after application, but in cv. ??Legory Hkcb?? dropped to very low levels 27?days after application. The degradation over time of the above pesticides in fruits was investigated in the peach cv. ??Andross??. The detected residue levels of bupirimate, iprodione, fenoxycarb, chlorpyrifos and pirimicarb in this peach cultivar were much lower than those recommended by the European Union (MRLs) 33, 22, 22, 28, and 63?days, respectively, after application, whereas the residue levels of chlorothalonil were below the limit of detection by the analytical method used. All pesticides showed a reduction over time. When examining the levels of residues of pirimicarb and chlorpyrifos in peaches (cv. ??Andross??) sampled from different parts of the tree canopy, no significant difference was found between samples collected from the top and the middle parts of the canopy; however, residues of pirimicarb were significantly higher in samples collected at the bottom of the canopy. Overall, the pesticide regime gave residue levels much lower than those of MRLs, in all peach??nectarine cultivars. This use of chemicals is in accordance with features of the new cultural systems to produce fruits with no or minimal pesticide residues, in contrast to the conventional system in which pesticide residues are not considered. Attention should however be paid to chlorpyrifos which should be applied at least 27?days before harvest. Factors related to the cultivars and the position of fruits in the tree canopy should be considered when sampling fruits for pesticide residues analysis. 相似文献
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R A Currie V W Kadis W E Breitkreitz G B Cunningham G W Bruns 《Pesticides monitoring journal》1979,13(2):52-55
Organochlorine pesticide residues were determined in human milk of residents of Alberta, Canada, during 1966-70 and 1977-78. Levels of polybrominated biphenyls (PBBs), polychlorinated biphenyls (PCBs), and some common organophosphorus pesticides were also monitored during 1977-78. Average residue levels were generally lower in 1977-78 samples, whereas the percent incidence of residues was generally lower in 1966-70 samples. beta-BHC was found in all 1977-78 samples, but was not detected in 1966-70 samples. PCBs were detected in all but two of the 1977-78 samples. Average levels of p,p'-DDT and is metabolites were substantially lower during the second period than during the first. Large increases in the average levels and percent incidences of heptachlor epoxide and o,p'-DDT have been attributed to refinements in both cleanup and gas chromatographic analysis. Although no PBBs or organophosphorus pesticides were detected in 1977-78 samples, an unidentified hydrocarbon similar to dicofol was found in all samples of that period. No correlation between donor age groups and average pesticide residue levels could be inferred. 相似文献
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BACKGROUND
Degradation kinetics of pesticides in plants are crucial for modeling mechanism-based pesticide residual concentrations. However, due to complex open-field conditions that involve multiple pesticide plant uptake and elimination processes, it is difficult to directly measure degradation kinetics of pesticides in plants. To address this limitation, we proposed a modeling approach for estimating degradation rate constants of pesticides in plants, using potato as a model crop. An operational tool was developed to backward-estimate degradation rate constants, and three pesticides were selected to perform example simulations.RESULTS
The simulation results of thiamethoxam indicated that the growth dynamics of the potato had a significant impact on the degradation kinetic estimates when the pesticide was applied during the early growth stage, as the size of the potato determined the uptake and elimination kinetics via diffusion. Using mepiquat, we demonstrated that geographical variations in weather conditions and soil properties led to significant differences in the dissipation kinetics in both potato plants and soil, which propagated the variability of the degradation rate constant. Simulation results of chlorpyrifos differed between two reported field studies, which is due to the effect of the vertical distribution of the residue concentration in the soil, which is not considered in the majority of recent studies.CONCLUSIONS
Our proposed approach is adaptable to plant growth dynamics, preharvest intervals, and multiple pesticide application events. In future research, it is expected that the proposed method will enable region-specific inputs to improve the estimation of the degradation kinetics of pesticides in plants. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献14.
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叶菜上农药原始沉积行为受作物形态、农药种类及其剂型、施用方式等多种因素的影响,是评估农药残留的重要指标。以吡虫啉和啶虫脒为目标农药,以菠菜和生菜作为靶标作物,通过农药施用后的原始沉积行为,以及兑水量、叶面积指数和农药剂型对农药沉积的影响,初步揭示了农药原始沉积规律。结果表明：施药后0.5～8 h内其沉积量无显著差异,综合考虑,选择施药后2 h时测定其原始沉积量;两种农药在菠菜和生菜中主要沉积在叶片表面,沉积量占比均在87%以上,在根和土壤中的沉积量较少;农药施药剂量相同而兑水量不同,则原始沉积量存在显著差异,随着兑水量的增加,沉积量逐渐减少;菠菜和生菜中农药沉积量与叶面积指数呈负相关;原始沉积量与剂型也有相关性,在施药剂量相同时,吡虫啉在菠菜、生菜中原始沉积量最高均为可湿性粉剂,沉积量分别为0.66和0.77 mg/kg;啶虫脒在菠菜中原始沉积量最高为乳油和可湿性粉剂,沉积量均为0.65 mg/kg,生菜中原始沉积量最高为可湿性粉剂,沉积量为0.37 mg/kg。研究结果认为,农药剂型、兑水量和叶面积指数均会影响叶菜表面农药原始沉积量,该结果可为叶菜中农药合理安全施用和农药残留管控提供... 相似文献
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为了有效地应对入世后出口蔬菜面临的种种技术壁垒挑战．2002年11月份起从出口蔬菜基地灌溉水和土壤农药残留普查、蔬菜农药残留量检测、基地所用农药有效成分分析、日本官方未登记农药监控4个方面,实施对宁波出口蔬菜基地农药残留量的监控工作。结果表明,基地灌溉水和土壤农药残留污染轻微,土壤农药残留量达到我国土壤环境质量一级与二级标准;蔬菜农药残留量控制良好,农药残留量均未超过输入国规定的限量要求：农药有效成分经分析与标识一致：重点监控了日本官方未登记或登记已失效而在宁波地区个别农民可能使用的农药,确保蔬菜的卫生质量。 相似文献
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Soil samples from five metropolitan areas including Baltimore, Maryland; Gadsden, Alabama; Hartford, Connecticut; Macon, Georgia; and Newport News, Virginia were analyzed for elemental arsenic, organochlorine pesticides, and polychlorinated biphenyls (PCBs). A representative number of samples were analyzed for organophosphorus pesticides, but none was detected. All areas exhibited heavy soil concentrations of organochlorine pesticides including sigma DDT, aldrin, dieldrin, photodieldrin, chlordane, heptachlor, heptachlor epoxide, endrin, endrin ketone, and endosulfan sulfate. PCBs were detected in three of the five metropolitan areas. Within the metropolitan areas, samples from the urban, or core city, locations generally had higher pesticide concentrations than did samples from suburban locations. Finally, pesticide residue concentrations were generally higher in soils of metropolitan areas than in nearby agricultural soils. 相似文献
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Soxhlet extraction with hexane + acetone (1 + 1 by volume) was used for the extraction of organochlorine pesticide residues from river sediments, followed by Florisil column chromatography clean-up and determination by gas chromatography with an electron-capture detector. Average recoveries exceeding 90 % were obtained using this technique. Organochlorine pesticide residue levels in sediment samples from two major rivers flowing through predominantly rice-growing areas were determined by this method. Relatively high residue levels of organochlorine pesticides such as HCH, heptachlor and endosulfan were found in the sediments. 相似文献