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1.
To estimate variations in pesticide residue levels in crops, the variability factors (VFs, the 97.5th percentile of the residue levels in the sample divided by the average residue levels in the lot) in residue levels of acetamiprid and cypermethrin applied to cabbage and grapes were investigated, respectively. The VFs in the residue levels of both pesticides in cabbage (2.00 and 2.39, respectively) were clearly higher than those in grapes (1.82 and 1.63, respectively). Although the residue levels of both pesticides in grapes showed a normal distribution, those values in cabbage were slightly skewed at lower residue levels. Individual residue levels in grapes had a good agreement between acetamiprid and cypermethrin. In contrast, the distribution of cypermethrin residue levels in cabbage was slightly skewed at higher residue levels as compared to that of acetamiprid. These results indicate that the difference in the relative distribution of the two pesticides between cabbage and grapes might be due to the influence of various factors such as differences in crop species, plant cultivation methods, and physicochemical properties of the pesticides. 相似文献
2.
Codex alimentarius approach to pesticide residue standards 总被引：1，自引：0，他引：1
R B Maybury 《Journal of the Association of Official Analytical Chemists》1989,72(3):538-541
To protect consumers' health, most countries have maximum legal limits for pesticide residues in foods. Trade difficulties can arise when limits differ between countries. The Codex Alimentarius Commission was established in 1962 to implement the Joint FAO/WHO Food Standards Programme, the purpose of which is to protect consumer health and ensure fair practices in international food trade. The Codex Committee on Pesticide Residues (CCPR), an intergovernmental body which advises the Commission on matters related to pesticide residues, is responsible for establishing maximum residue limits (MRLs) for pesticides in foods and feeds that move in international trade. Codex MRLs are based on residue data obtained mainly from supervised trials that reflect approved pesticide use in accordance with "good agricultural practice." MRLs must be toxicologically acceptable in terms of estimated pesticide intake by consumers. CCPR Working Groups examine problems related to establishing and implementing MRLs, including sampling and methods of analysis. Despite time and effort expended, acceptance and application of Codex MRLs face many problems in international trade. 相似文献
3.
Angioni A Dedola F Garau VL Schirra M Caboni P 《Journal of agricultural and food chemistry》2011,59(12):6806-6812
The behavior in field and the transfer from grapes to wine during winemaking of iprovalicarb, indoxacarb, and boscalid was studied. The residue levels found in grapes were far below the MRLs set for grapes in EU, accounting at harvest time 0.81, 0.43, and 4.23 mg/kg for iprovalicarb, indoxacarb, and boscalid, respectively. The residue levels in the samples treated with boscalid may have residual problems (due to an accumulation effect) if repeated field treatments will be performed. Winemaking experiments showed a complete transfer of all pesticide from grapes to the must, while in wine the residues were low or negligible due to the adsorbing effect of lees and pomace. The clarification experiments showed a good removal of pesticide residues from the wine media, for all pesticides. The GC-ITMS method showed good performance with adequate recoveries ranging from 75 to 115%, and good method limits of quantitation (LOQs) and of determination (LODs) far below MRLs. 相似文献
4.
A specifically designed field trial was carried out in an apple orchard by applying Reldan 50 EC (active ingredient, chlorpyrifos-methyl) according to registered uses in Hungary to study the variability of results derived from supervised field trials. Two types of composite samples (A, size 24; and C, size 12) were taken at days 0, 3, 7, 10, and 14 after application to study the uncertainty of estimated residue values derived from supervised trials. In the case of type A the sampling officer selected the fruits from the specified quadrant of the tree, whereas for type C the fruits were taken from the vicinity of the marked position at consecutive sampling times. An evaluation model applying various formulas for the linearization of the decline curves of pesticide residues was applied, which enabled using the statistics of linear regression for calculating the best fit and confidence intervals for the experimental data. The results indicated that the uncertainty of sampling contributed approximately 84-90% of the combined uncertainty of the results (24-30%). In the decline studies performed simultaneously on the same field, the estimated time required to decrease the initial concentration to half ranged from 0.64 to 4.7 days. Despite the fact that the sample size of type C is half that of type A, both sampling methods provided similar results. 相似文献
5.
Salas JH González MM Noa M Pérez NA Díaz G Gutiérrez R Zazueta H Osuna I 《Journal of agricultural and food chemistry》2003,51(15):4468-4471
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
6.
Otake T Yarita T Aoyagi Y Kuroda Y Numata M Iwata H Mizukoshi K Nakamura M Watai M Mitsuda H Fujikawa T Ota H 《Journal of agricultural and food chemistry》2011,59(16):8568-8574
Green onion and cabbage certified reference materials for the analysis of pesticide residues were issued by the National Metrology Institute of Japan, part of the National Institute of Advanced Industrial Science and Technology. Green onion and cabbage samples were grown so as to contain several kinds of organophosphorus and pyrethroid pesticides, and those were collected from a field in the Kochi Prefecture in Japan. The certification was carried out by using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides (diazinon, fenitrothion, cypermethrin, etofenprox, and permethrin for green onion and chlorpyrifos, fenitrothion, and permethrin for cabbage) were obtained by isotope dilution mass spectrometry. Certified values of target pesticides were 0.96-13.9 and 2.41-6.9 mg/kg for green onion and cabbage, respectively. These are the first green onion and cabbage powder certified reference materials in which organophosphorus and pyrethroid pesticides are determined. 相似文献
7.
Ripley BD Ritcey GM Harris CR Denommé MA Lissemore LI 《Journal of agricultural and food chemistry》2003,51(5):1328-1335
The behavior and dissipation of several pesticides on selected cultivars of specialty vegetable crops were compared to determine appropriate preharvest intervals for compliance with maximum residue limits. To reduce application variability, a tank mix of pesticides was applied for each trial. Residues of eight pesticides applied to bok choi, Chinese broccoli, and fuzzy squash were similar for the two leafy vegetables; residues were higher than on squash because of the latter's larger mass-to-surface area ratio. Whereas residues of five of the nine pesticides applied to cabbage, Chinese cabbage, and bok choi did not differ significantly from 3 to 14 days after application, residues of cypermethrin and three fungicides were significantly higher on Chinese cabbage and bok choi. The residue deposits of the pesticides were about 50% lower on Chinese cabbage and 90% lower on cabbage than on bok choi. Dissipation of residues on different cultivars of lettuce and cabbage were compared after application of nine pesticides. With the exception of captan, residues on head lettuce were lower than on the other lettuces on day 1; cultivar differences were not significant for most of the nine applied pesticides on days 3 and 8. Generally, residues of the nine individual pesticides on storage cabbage, savoy cabbage, Chinese cabbage, and tah tsai did not differ significantly from day 1 to day 7 after application. Residue concentrations were generally significantly higher on bok choi than on the other cultivars. Residue deposits generally correlated with the rate of application; residues of captan, however, were about 50% of the predicted value. Significant differences in deposit and dissipation were observed among cultivars and pesticides, with dramatic initial decreases for diazinon and parathion. Because of their higher exposed surface area-to-mass ratios, leafier crops had higher residue concentrations than head varieties. Residues on lettuce cultivars were higher than on the cabbages. The results clearly indicate that structure significantly affects residue deposit and dissipation, and pesticide recommendations cannot always be extended to specialty crops without an investigation of the changes in preharvest intervals to prevent violations of the maximum residue limits. 相似文献
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9.
M A Luke H T Masumoto T Cairns H K Hundley 《Journal of the Association of Official Analytical Chemists》1988,71(2):415-433
During a 5 year period from 1982 to 1986, the FDA Los Angeles District Laboratory analyzed 19,851 samples of domestic and imported food and feed commodities for pesticide residues. A single, rapid, multiresidue method was used. The resultant data have been compiled showing the commodities sampled and the identity and range of levels of pesticide residues detected, including an indication of those residue findings that did not comply with U.S. federal tolerance levels. The residue data presented should not be viewed as being representative of the U.S. food supply; rather, the results are indicative of a surveillance- and compliance-oriented sampling of various food shipments collected by the Los Angeles District. 相似文献
10.
The behavior in the field and the transfer from olives to olive oil during the technological process of imidacloprid, thiacloprid, and spinosad were studied. The extraction method used was effective in extracting the analytes of interest, and no interfering peaks were detected in the chromatogram. The residue levels found in olives after treatment were 0.14, 0.04, and 0.30 mg/kg for imidacloprid, thiacloprid, and spinosad, respectively, far below the maximum residue levels (MRLs) set for these insecticides in EU. At the preharvest interval (PHI), no residue was detected for imidacloprid and thiacloprid, while spinosad showed a residue level of 0.04 mg/kg. The study of the effect of the technological process on pesticide transfer in olive oil showed that these insecticides tend to remain in the olive cake. The LC/DAD/ESI/MS method showed good performance with adequate recoveries ranging from 80 to 119% and good method limits of quantitation (LOQs) and of determination (LODs). No matrix effect was detected. 相似文献
11.
P Lombardo 《Journal of the Association of Official Analytical Chemists》1989,72(3):518-520
The U.S. Food and Drug Administration (FDA) has carried out a large-scale monitoring program for pesticide residues in foods since the 1960s. The program has evolved continuously as evidenced by a number of recently incorporated modifications and initiatives. Included are greater emphasis on imports; increased and more specific targeting of pesticide/commodity combinations by geographic area or country; development of individual district sampling plans for domestic and imported foods; expanded use of single residue methods; linkage of information on foreign pesticide usage with food import volumes; development of an analytical methods research plan; and increased cooperative sampling and data exchange with the states. Initiatives to acquire and utilize private sector and other monitoring data are being explored, and aggressive steps are being taken to inform the public of FDA monitoring results in a timely and understandable manner. 相似文献
12.
采用长期定位施肥试验土壤（轻壤质黄潮土），研究不同施肥条件下，氯氰菊酯降解变化和对土壤酶活性的影响。结果表明，不同的施肥处理对土壤中氯氰菊酯的降解行为有显著影响，长期施用氮肥，土壤中速效氮含量升高，对氯氰菊酯降解有抑制作用；施用磷肥则促进降解；施用有机肥在提高土壤有机质含量的同时，虽加速了氯氰菊酯降解，但降解延滞期和残留期有所增加。氯氰菊酯在土壤中的降解遵循一级动力学方程，降解半衰期为10．13d（PK）～14．58d（NK）。土壤中加入氯氰菊酯后，脱氢酶、脲酶活性有所升高，施肥处理不同，升高幅度也不一样．均达显著水平。磷酸酶活性变化在不同施肥处理中，表现不一样。培养26d左右，土壤酶活性大多都能恢复到初始水平。研究土壤中农药残留与施肥、土壤酶活性的关系，对于实现农业可持续发展具有重要意义。 相似文献
13.
Fernández-Cruz ML Villarroya M Llanos S Alonso-Prados JL García-Baudín JM 《Journal of agricultural and food chemistry》2004,52(4):860-863
Field trials have been carried out to determine the variability of residue levels of fenitrothion and its main metabolites fenitrothion-oxon and 3-methyl-4-nitrophenol in individual kaki fruits versus composite samples, in peel versus flesh, and in whole uncooked versus whole cooked fruits. Residue levels have been determined by gas chromatography with thermionic specific detection after extraction with ethyl acetate and without further cleanup. At harvest, residue levels of fenitrothion were below maximum residue levels (MRLs) and the two metabolites 3-methyl-4-nitrophenol and fenitrothion-oxon could be quantified with average amounts of 0.080 and 0.012 mg/kg, respectively. Levels of fenitrothion decreased 88% after peeling, whereas temperature did not result in a high variation. The ratios of the highest residue level in the individual fruits to the corresponding mean of residue levels in the composite samples for fenitrothion were <3. This value is lower than that recommended by the World Health Organization as default value for consumer risk assessment. 相似文献
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15.
土壤重金属调查采样数目的确定方法研究进展 总被引：2，自引：1，他引：1
在土壤重金属调查中,合理确定采样单元的采样数目对保障其数据精确性及土壤污染风险评估和防治具有重要意义。该文通过广泛查阅国内外相关文献,对表层土壤重金属采样数目确定方法现状及未来研究方向进行了评述;基于经验型、统计学及经验统计学方法系统分析了土壤重金属采样数目确定方法的优缺点。结果显示在确定采样数目时缺乏对采样单元的考虑;采样数目更多的集中于经验型,相对缺乏基于统计学及经验统计学的应用。在采用统计学方法确定采样数目时,更多地集中于正态分布下的采样数目确定,而大多忽视了土壤重金属含量的非正态分布及其对采样数目的影响;尽管有部分学者提出对数正态分布下采样数目的确定方法,但是该分布下采样数目的精确算法过于复杂,不同修正公式的应用范围也有所限制,不足以涵盖在不同变异下的采样布点,而且存在高估或低估采样数目的风险。因此,明确采样尺度或采样单元,加强基于统计学或经验统计学确定采样数目方法的研究,探索对数正态分布下合理采样数目的确定方法,寻找出适合中国土壤重金属采样数目确定方法是实现土壤重金属风险评估和污染治理的重要保障。 相似文献
16.
以鲤鱼为研究对象,对常用农药氯氰菊酯通过食物链（蔬菜-黄粉虫幼虫-鲤鱼）在鲤鱼肾脏和小肠内的富集效应进行了研究。饲喂的蔬菜农药残留剂量为2．00mg·kg^-1和10．00mg·kg^-1,通过HPLC定量检测黄粉虫幼虫体内及鲤鱼肾脏和小肠内氯氰菊酯的富集浓度,同时对鲤鱼肾脏和小肠组织结构进行了观察。结果显示,氯氰菊酯在黄粉虫幼虫及鲤鱼体内的富集浓度与剂量呈正相关,在食物链中的富集呈逐级递增,且对黄粉虫幼虫及鲤鱼的摄食情况及活动能力有明显的影响,随着处理时间的延长及剂量的增大,氯氰菊酯对鲤鱼肾脏及小肠结构损伤程度也增大。因此,杀虫剂氯氰菊酯的使用会通过食物链对环境中生物乃至人类健康和生态平衡造成影响,应慎重使用。 相似文献
17.
Albero B Sánchez-Brunete C Tadeo JL 《Journal of agricultural and food chemistry》2003,51(24):6915-6921
A rapid multiresidue method was developed for the determination of nine organophosphorus pesticides in fruit juices. The analytical procedure is based on the matrix solid-phase dispersion (MSPD) of juice samples on Florisil in small glass columns and subsequent extraction with ethyl acetate assisted by sonication. Residue levels were determined by gas chromatography with nitrogen-phosphorus detection. Spiked blank samples were used as standards to counteract the matrix effect observed in the chromatographic determination. The NPD response for all pesticides was linear in the concentration range studied with determination coefficients >0.999. Average recoveries obtained for all of the pesticides in the different juices and fortification levels were >70% with relative standard deviations of <11%. The detection limits ranged from 0.1 to 0.6 microg/kg. The identity of the pesticides was confirmed by gas chromatography with mass spectrometric detection using selected ion monitoring. The proposed MSPD method was applied to determine pesticide residue levels in fruit juices sold in Spanish supermarkets. At least one pesticide was found in most of the samples, although the levels detected were very low, far from the maximum residue levels established for raw fruit. 相似文献
18.
S M Dogheim E N Nasr M M Almaz M M el-Tohamy 《Journal of the Association of Official Analytical Chemists》1990,73(1):19-21
Because of the intensive use of pesticides for the control of certain pests in Egypt, country-wide residue monitoring programs must be established that can cover all the Egyptian Governorates exposed to pesticide treatments. To do so, limited programs must be adopted first, so that current situations and future needs for improved programs are identified. The present paper reports results from a limited monitoring program, which started in 1985 in one governorate and then expanded to include another in 1986. Fish and milk samples were the commodities selected for residue analysis. The results showed that milk samples collected from Beni-Suef Governorate in 1986 had lower levels of organochlorine residues compared to those collected in 1985. Residues in boltifish and catfish samples in 1986 were much higher than those detected in 1985. In comparison with Beni-Suef Governorate, and contrary to expectations, milk derived from Fayoum Governorate in 1986 was more contaminated with pesticides. While the amount of residues in boltifish was comparatively higher, catfish samples were less contaminated. 相似文献
19.
Brown P Garner C Glass R Ridgway C Hart A 《Journal of agricultural and food chemistry》2004,52(12):3693-3701
Methods to refine the assessment of exposure of wild birds and mammals to pesticides required measurement of pesticide residues in very small samples of their diets. Sample sizes were in the 1-100 mg range, and the target residue for measurement was 0.01 mg/kg. Gas chromatography-mass spectrometry (GC-MS) with large volume injection was compared with the use of an accelerator mass spectrometer (AMS) to measure residues of pesticide labeled at near-background levels with carbon-14. The GC-MS method was able to detect residues down to 0.1 ng per item of diet, and the AMS detected the radiolabel down to 1 mBq (0.06 disintegration per minute, 1 ng of pesticide at the specific activity used) per sample. The target residue level was achieved by the GC-MS method for samples down to 10 mg. The GC method appeared to be best suited to monitoring residues in field studies, and the AMS shows great potential for use in laboratory experiments concerning pesticide degradation. 相似文献
20.
Investigations into forest soils face the problem of the high level of spatial variability that is an inherent property of all forest soils. In order to investigate the effect of changes in residue management practices on soil properties in hoop pine （Araucaria cunninghamii Aiton ex A. Cunn.） plantations of subtropical Australia it was important to understand the intensity of sampling effort required to overcome the spatial variability induced by those changes. Harvest residues were formed into windrows to prevent nitrogen （N） losses through volatilisation and erosion that had previously occurred as a result of pile and burn operations. We selected second rotation （2R） hoop pine sites where the windrows （10-15 m apart） had been formed 1, 2 and 3 years prior to sampling in order to examine the spatial variability in soil carbon （C） and N and in potential mineralisable N （PMN） in the areas beneath and between （inter-） the windrows. We examined the implications of soil variability on the number of samples required to detect differences in means for specific soil properties, at different ages and at specified levels of accuracy. Sample size needed to accurately reflect differences between means was not affected by the position where the samples were taken relative to the windrows but differed according to the parameter to be sampled. The relative soil sampling size required for detecting differences between means of a soil property in the inter-windrow and beneath-windrow positions was highly dependent on the soil property assessed and the acceptable relative sampling error. An alternative strategy for soil sampling should be considered, if the estimated sample size exceeds 50 replications. The possible solution to this problem is collection of composite soil samples allowing a substantial reduction in the number of samples required for chemical analysis without loss in the precision of the mean estimates for a particular soil property. 相似文献