首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 312 毫秒
1.
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   

2.
农药在防治病虫害、提高农产品产量和质量方面效果显著,但一些农药因高毒、致癌、致畸、致突变、代谢缓慢,对人类和环境产生不利影响而被我国禁止或限制使用。有机氯类禁限用农药作为其中产量最多、用量最大的一类,存在较高的健康或环境风险而备受关注。建立高效便捷的有机氯类禁限用农药残留的检测方法,对确保食品安全、助力绿色生态农业发展、打破食品进出口技术贸易壁垒具有重要意义。免疫分析法以其快速、简便、灵敏等优势被广泛应用于食品中农药残留的检测。本文综述了有机氯类禁限用农药免疫检测方法的研究进展,介绍了半抗原的合成和抗体的制备,总结了抗体在免疫检测中的应用,主要包括酶联免疫分析法、免疫层析试纸条法、化学发光法、荧光免疫分析法和免疫传感器,可对未来有机氯类禁限用农药免疫分析法的进一步研究开发提供参考。  相似文献   

3.
BACKGROUND: Environmental pesticides, including insecticides and herbicides, are frequently encountered as mixtures and threaten non‐target organisms in water. Evaluation of the combined toxicity of diverse pesticides with various concentration combinations is important, especially using limited experimental effort. Uniform design (UD) is one optimal experimental technique that can rationally arrange the concentrations of mixture components so that, with a minimum number of experimental runs, the combined toxicity of multiple pesticide mixtures can be evaluated. RESULTS: The concentration compositions of 18 pesticide mixture points designed by UD covered almost all possible concentration ranges of the mixture components on account of the two merits of ‘space filling’ and ‘multiple levels’. The combined toxicities of 18 mixture rays extended by using the fixed‐ratio ray design (FRRD) from 18 UD mixture points were evaluated by concentration addition (CA) and independent action (IA) models. It was found that the concentration–response curves (CRCs) predicted by CA were, on the whole, located between the 95% confidence intervals of the experimental CRCs, which implied that the combined toxicity of the pesticide mixture rays could be evaluated by CA. The CRCs predicted by IA were very similar to those from CA. CONCLUSION: The model developed from the UD mixture rays can effectively simulate mixtures with arbitrary concentration compositions of 15 pesticides. The CA model can accurately evaluate and predict the combined toxicity of the pesticides, which provides a useful tool for risk assessment of a mixture of multiple pesticides in the aquatic environment. Copyright © 2010 Society of Chemical Industry  相似文献   

4.
农药是保障粮食安全的重要农业投入品,施用后部分农药会沉积在土壤中,甚至会被作物根部吸收,进入作物体内并累积于可食部位,从而导致潜在农产品质量安全问题。研究表明,土壤中的有机质含量、农药的辛醇-水分配系数和作物脂质含量是影响作物吸收非离子型农药的关键因素,作物各部位的脂质含量是影响该类农药累积的关键因素,借助蒸腾作用向上传递是作物根部吸收传导农药的主要动力。本文重点综述了农药被作物的根部吸收、传递和累积及其主要影响因素,结合植物吸收模型的发展及运用,展望了该领域未来发展方向,为农药归趋及应用风险研究提供参考。  相似文献   

5.
6.
BACKGROUND: Pesticide residues remaining on food represent a potential risk to consumer's health. Determination of these pesticide residues involves tedious procedures of analysis with regard to time and laboratory work. Near‐infrared spectroscopy (NIRS) is a possible alternative to these methods. The aim of this research was to evaluate the ability of NIRS to classify two pesticides used for controlling apple fruit pests according to their concentration. Different solutions were prepared, based on the dose recommended by the pesticide producers for apple pest treatments. Spectra were acquired on a spectrophotometer from liquid samples belonging to these solutions. RESULTS: Calibration models were developed from liquid samples, following the soft independent modelling of class analogy (SIMCA) analysis method. These models classified between 99 and 100% of the validation samples belonging to different pesticide concentration solutions even at the maximum residue limit level of these products in apple fruit. CONCLUSIONS: NIRS technology shows a high potential for identifying pesticides in liquid samples, according to their concentration, at the levels required by the legislation. © 2012 Society of Chemical Industry  相似文献   

7.
WRc are undertaking a long term study of pesticides in the aquatic environment. A study of the pesticides in the rain, river water and groundwater of the Granta catchment in Cambridgeshire is now in its fourth year. Preliminary results are presented and the concentrations of agricultural pesticides in environmental waters are related to the land-use within the catchment. The Granta study is incomplete but certain anomalies in pesticide occurrence can be identified. In particular, the triazines are much more prevalent in the groundwaters than their agricultural usage would lead one to expect. The limited data base gives problems with modelling the contaminant transport in groundwater. The present situation is reviewed and areas of future work necessary to fulfil the modelling needs identified. These areas of study. The historical land-use and pesticide usage; the groundwater quality data base; the pesticide transport in the unsaturated zone.  相似文献   

8.
The evolution of resistance to pesticides is often conceptualised and modelled at a population level, but population‐based approaches ignore important aspects of variability between individuals within populations that may be essential drivers of resistance. Here it is argued that individual‐based modelling has the potential to generate new insights and perspectives, thus deepening our understanding of the complexities of the evolutionary dynamics of resistance to pesticides. Copyright © 2012 Society of Chemical Industry  相似文献   

9.
我国有占世界19%的人口,但仅有占世界9%的耕地,因此保证国家粮食安全是头等大事。在确保生态环境安全的前提下,如何增加作物产量和保障农产品质量安全始终是我国农业快速发展面临的一大挑战。在高效、负责、透明的政府能力建设中,我国农业的绿色发展和高质量发展战略,我国农药管理的法制建设、市场监管、食品安全、环境监测、有害生物治理、应用技术服务及推广等都取得了显著进步。到2021年底,我国已经登记了740多个农药有效成分,41 433个农药产品。2021年,全国1 705家农药定点企业,共生产了化学农药原药249.8万t。不仅满足了国内有害生物防控的实际需要,还出口180多个国家和地区,农药出口额达到234亿美金。我国还有的10个高毒农药品种,已经控制在1.3%以下,且安排在未来5年内会陆续退市。本文还分析梳理了今后我国农药管理发展所面临的挑战。  相似文献   

10.
An argument is presented by which the role of pharmaceuticals and pesticides can both be viewed in terms of contributing to human health. Comparisons are made in terms of discovery and development, regulatory policies and environmental and human impacts. Both technologies target particular biological functions, and in many cases they target similar molecular sites of action. Pharmaceuticals and pesticides undergo a similar registration process; however, both can enter the environment where they can have adverse effects on non-target organisms and, if misused, will have detrimental effects on human health or the environment. It is suggested that the risks associated with the two technologies are similar. The rejection of pesticides by the general public is based primarily on personal value systems and the uncertainty of risk management. It is concluded that plant and animal health are vital to maintaining human health, and that pesticides used in food production are, as with pharmaceuticals, a vital tool used to maintain human health.  相似文献   

11.
Isoboles,a graphic representation of synergism in pesticides   总被引:1,自引:0,他引:1  
It is possible to give a graphic representation of the effect of two pesticides applied jointly or of the effect of pesticides to which substances have been added. Each of the components is expressed in a coordinate. In the graph a quantitatively defined effect, e.g. a mortality of 50%, is inserted. These values are obtained by interpolation. The line which connects the points is called an isobole afterLoewe & Muischnek (1926) who used it for drugs. With an isobole the effect of different proportions of the components can be evaluated. The various types of isoboles are described and illustrated for some experiments with insecticides, herbicides and fungicides.  相似文献   

12.
Monte Carlo techniques are increasingly used in pesticide exposure modelling to evaluate the uncertainty in predictions arising from uncertainty in input parameters and to estimate the confidence that should be assigned to modelling results. The approach typically involves running a deterministic model repeatedly for a large number of input values sampled from statistical distributions. A key decision in setting up a probabilistic analysis is whether there is correlation between any of the inputs to the analysis. Pesticide properties are often the most sensitive in exposure assessment. Analysis of the literature demonstrated that there are examples of both positive and negative correlation between the sorption and degradation behaviour of a pesticide, but that general trends are not apparent at present. The inclusion of even weak correlation between sorption and degradation was found to greatly influence a probabilistic analysis of leaching through soil. Correlation will reduce the predicted extent of leaching for pesticides, and it is recommended to set the correlation to zero unless the experimental data support an alternative assumption (i.e. where the correlation is statistically significant (P 相似文献   

13.
为研究农产品中农药混合污染的联合毒性,选取生菜中应用广泛、广谱性强的5种农药(苯醚甲环唑、氯氰菊酯、烯酰吗啉、氯氟氰菊酯和啶虫脒)及其高频检出的二元、三元农药组合为研究对象,采用CCK-8 (Cell Counting Assay Kit-8) 法探究农药单剂及混合物对人肝癌HepG2细胞增殖的抑制毒性,基于单个农药剂量效应曲线按照等效应的联合毒性测定方法,应用浓度相加、独立作用和联合指数3个预测模型推导联合效应,并通过高内涵筛选系统分析农药混合物对人肝癌HepG2细胞凋亡的诱导作用。结果表明:不同农药对HepG2细胞增殖抑制的影响存在较大差异,但均具有明显的剂量-效应关系,其中苯醚甲环唑具有最强的细胞增殖抑制毒性,细胞活力的半数抑制浓度 (EC50) 为24.72 μmol/L;其余农药毒性顺序为烯酰吗啉 > 氯氟氰菊酯 > 啶虫脒 > 氯氰菊酯。通过联合指数判定农药混合物的联合毒性效应的结果表明:所有二元组合均随农药浓度增大表现出细胞增殖抑制效应增强,联合效应由拮抗转为协同;三元组合烯酰吗啉 + 苯醚甲环唑 + 氯氰菊酯、烯酰吗啉 + 氯氰菊酯 + 啶虫脒的细胞增殖抑制效应分别为60%和18%时,联合效应由协同转为拮抗。同时,利用剂量减少指数量化农药混合物之间的协同效应研究表明,在上述两个三元组合的协同效应中,氯氰菊酯发挥较大作用。在凋亡毒性测定中,各农药单独处理组均会造成HepG2细胞凋亡率的显著提高,且呈剂量依赖性;三元组合烯酰吗啉 + 氯氰菊酯 + 啶虫脒在20.02~80.10 μmol/L浓度范围内可诱导细胞凋亡水平显著提升。本研究明确了农药单剂和混合物对HepG2细胞增殖和凋亡毒性具有明显的剂量依赖效应,可为混合农药毒性评价以及风险监测提供科学依据。联合指数模型可以定量地描述农药混合物在不同组分和浓度下的相互作用,对比浓度相加和独立作用模型,可较准确地预测混合物的联合毒性,是一种有效的生态毒理学风险评估工具。  相似文献   

14.
基于纳米递送系统的RNA农药及转基因植物研究进展   总被引:1,自引:1,他引:0  
近年来,转基因植物和RNA农药作为绿色可持续发展农业的重要组成部分受到越来越多的关注.传统的基因工程元件和RNA农药递送策略往往会受到多种外界因素的干扰,造成效率偏低甚至失效,这也是限制植物基因工程和RNA农药发展的主要技术瓶颈.基于纳米载体的新型递送系统与植物基因工程和RNA干扰技术的结合展现出了广阔的应用前景.本文...  相似文献   

15.
化学农药作为一种农业生产必须的投入品,自发明以来,极大地促进了作物丰产、保障了粮食作物安全,但化学农药的滥用造成了农产品污染,同时对生态环境也造成严重破坏。生物农药作为一种绿色农药,近年来正逐渐替代化学农药的使用。"化学肥料和农药减施增效综合技术研发"重点专项针对我国化肥农药施用过量、产品研发落后等问题,2016-2018年,启动了12项任务,共计49个项目,专项的实施促进了我国绿色农药产品研发和推广应用。本文对专项的生物源农药产品研发、专利申请、标准制定、专著出版、技术应用等方面进行了总结,以供生物源农药研发、生产与应用领域内的科研工作者、生产与经营主体、管理部门、使用用户等参考。  相似文献   

16.
本文论述了农药在现代农业中保障粮食安全的重要作用;分析了农药生产和使用存在的主要问题,以及农药应用风险对粮食安全的负效应;提出了加大农药监控力度,控制和削减化学农药,加快生物农药发展步伐,提高科学使用农药的实施意见。  相似文献   

17.
With the harmonisation of data requirements for pesticide registration under EC Directive 91/414 there is need for progress on the techniques used to analyse such data and so help make consistent the judgements applied by national regulatory authorities. This paper proposes a Bayesian technique for combining data from environmental fate and behaviour studies of pesticides in soil. The method uses expert knowledge, based on degradation and adsorption data, and logistic regression methods to form a prior probability distribution for the probability that a given compound leaches. Results from lysimeter experiments are used update the prior knowledge. Data for the compounds bentazone and triclopyr are used to illustrate the techniques. The advantages of the methodology and its implications for the pesticide registration procedure are discussed in the light of possible advances using modern Bayesian statistical techniques and mathematical models. © 1998 Society of Chemical Industry  相似文献   

18.
禁止和限制使用农药残留限量的是政府加强消费安全、环境安全和农业产业安全保护的重要技术措施。本文在介绍国际组织和欧美等发达国家禁限用农药残留限量制定原则的基础上,对我国禁止和限制使用农药残留限量制定背景、原则和程序进行了详细解读。  相似文献   

19.
Food is a highly complex substance and its qualities are measured in many ways. One of the most important quality attributes is flavour, and this is a complicated characteristic probably because of the subtle nature of the many chemical substances involved in producing it. The care which is taken by food manufacturers in the United Kingdom ensures that, in general, products are of good flavour quality but very occasionally, taints do arise and pesticides are sometimes blamed for the off-flavours produced. Although the whole field of taint experimentation is not an easy one to investigate, the work at Chipping Campden on this subject began nearly thirty years ago and is now well established and recognised. A number of pesticides are now known to have tainting characteristics.  相似文献   

20.

BACKGROUND

Pesticide residues in animal feed can endanger animal health and compromise the safety of livestock products for human consumption. Even though policymakers such as the European Union and the World Health Organization have established maximum residue levels (MRLs) for pesticides in both human food and animal feed, there is no systematic management of pesticides in animal feed that considers the entire supply chain. In response, we propose a framework for defining consistent MRLs for pesticides in animal feed that assesses the impact of defined MRLs on upstream (e.g., MRLs in feed crops) and downstream (e.g., MRLs in livestock products) sectors of the livestock-product supply chain.

RESULTS

The MRLs determined for the selected pesticides in the feed of cattle and sheep as case study animals indicate that lipophilic pesticides tend to have lower MRLs than hydrophilic pesticides, primarily due to the relatively high toxicity and biotransfer factors of lipophilic pesticides. In addition, we observe that, primarily for lipophilic pesticides, upstream and downstream regulations are not aligned in terms of defining MRLs in feed using current MRLs in crops with relevance to feed and foods of animal origin.

CONCLUSION

Some of the current pesticide regulations in the livestock-product supply chain need to be re-evaluated to ensure that MRLs in the upstream sector (i.e., crops) do not result in unacceptable residues in the downstream sector (i.e., MRLs in livestock products affecting animal and human health). Finally, we provide recommendations for optimizing the derivation of MRLs in feed, including the evaluation of residue fate during feed and food manufacturing processes. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号