Prioritization of pesticide environmental transformation products in drinking water supplies

Receiving waters within catchments may be exposed to many different transformation products following the application of pesticides. As environmental waters are abstracted for drinking water treatment these compounds may pose a risk to human health. This paper describes a prioritization approach for identifying the most important transformation products in drinking water sources. The approach can be applied to different geographical areas that have suitable pesticide usage data. The risk based approach incorporates data on pesticide usage and toxicity as well as transformation product formation, mobility, and persistence. The application of the approach is illustrated for two geographical areas that have good quality pesticide usage data: Great Britain and California. The transformation products with the highest risk index and a complete experimentally derived data set for Great Britain were 3,5,6-trichloro-2-pyridinol, thifensulfuron acid, and kresoxim-methyl acid and for California were carbendazim, aldicarb sulfoxide, and RP30228.     

Occurrence of pesticide residues and transformation products in different types of dietary supplements

The purpose of this study was to evaluate the presence of pesticide residues and transformation products in dietary supplement products. Thirty-two samples were analysed to determine 177 pesticides by gas chromatography–tandem mass spectrometry (GC-MS/MS) and 333 pesticides by liquid chromatography–high-resolution mass spectrometry (LC-HRMS). Pesticides were extracted from different kinds of dietary supplements by the use of a modified QuEChERS extraction method. Six samples contained pesticide residues at concentration up to 92.7 µg kg^?1, but only butralin exceeded the maximum residue limits set for raw material. In addition to target compounds, LC-HRMS enables the simultaneous detection of non-target pesticides. In this case, transformation products of pesticides were detected in the analysed samples using HRMS analyser (Exactive-Orbitrap). These compounds were not included in the original method, and they were monitored as post-target compounds, knowing their molecular formula and exact mass. Mass accuracy was always < 2 ppm, corresponding to a maximum mass error. The positive findings endorse the idea that a deeper and continuous investigation of pesticide residues and transformation products in dietary supplement products is necessary in order to guaranty consumer’s safety.     

农产品中农药残留预警系统的构建

随着社会经济的快速发展,人民生活水平的不断提高,民众对农产品安全问题也越来越关注.影响农产品安全的一个重要因素,就是农药残留问题.目前对农药残留的研究主要集中在检测技术和监测等方面,但缺乏对农药残留预警工作的研究探讨.因此,该文在介绍构建农产品农药残留预警系统重要意义的基础上,提出了建立农产品农药残留预警系统的原理和基本框架,同时阐述了其主要功能,为其它食品安全关键项目预警系统的建立提供参考.     

Fate of foodborne bacterial pathogens in pesticide products

The effects of diluting concentrated pesticide products with water containing Escherichia coli O157:H7 (human, bovine and ground meat strains), Salmonella typhimurium, Salmonella enteritidis, Shigella sonnei, Shigella flexneri and Listeria monocytogenes were investigated. Individual cultures were inoculated at about 10² colony‐forming units (cfu) ml^?1 into the following commercial pesticide products—Roundup, Poast & Merge, Gramoxone, Afolan, 2,4‐D amine, Dithane M45, Benlate, Bravo 500, Ridomil 240EC, Thiram 75WP, Sevin XLR+, Lorsban 4E, Diazinon 500, Ambush 500EC and Lagon 480E—following dilution with sterile tap water to recommended spray application concentrations (pesticide solution). Following incubation at 22 °C for 1 h, survivor levels for all three E coli O157:H7 strains in pesticide solutions of Roundup, Poast & Merge, Gramoxone, Dithane M45, Ridomil 240EC and Lagon 480E were lower (P ≤ 0.05) compared to their survival in water. In several pesticide solutions (Afolan, Bravo 500, Lorsban 4E and Ambush 500EC), survivor levels were no different (P≥0.05) from the control after 1 h; however, by 24 h, population levels of all strains in these four pesticide solutions were higher (P ≤ 0.05) than those observed at 1 h. Overall, similar survivor or growth patterns were observed with the remaining bacteria, with the exception of S flexneri. For this bacterium, survival or growth was poor, especially in Bravo 500, which consistently supported substantial growth of the other micro‐organisms. Time course growth studies over 96 h at 22 °C were conducted with Salmonella, Shigella, Listeria and E coli O157:H7 in solutions of Afolan, Bravo 500, Lorsban 4E and Ambush 500EC. Overall, a 100 to 1060‐fold increase in population was usually obtained in these pesticide solutions by 96 h. Changes in either the initial inoculum level of E coli O157:H7 from about 10² to 10⁴ cfu ml^?1 or temperature (from 20–22 to 31 °C) and concentration (from 0.5 to 1.5 times the recommended spray concentration) were shown to affect its growth in the pesticide solutions. The findings of this study indicate that some pesticide products, when diluted using contaminated water, may have the potential to promote growth of pathogens which could increase the risk of more widespread contamination of standing crops, including fruits. © 2001 Society of Chemical Industry     

Assessing the risks of pesticide residues to consumers: recent and future developments

Assessing exposure of consumers to pesticide residues is an area of regulatory science that has rapidly developed over the last decade. From simplistic, deterministic models calculating lifetime exposure for adults only, assessment procedures have diversified so that more realistic estimates of long term exposures for adults, schoolchildren, toddlers and infants and short term exposures for adults and toddlers (who generally bound the more extreme consumer patterns) are now carried out. The final assessment of risk still remains a simplistic numeric comparison against hazard assessment based on a wide range of toxicity studies incorporating the appropriate safety or uncertainty factors. As development of risk assessments continues, the use of probabilistic models is becoming an invaluable information tool for quantitative risk management and aiding assessment of cumulative exposure. This paper examines the recent developments in risk assessment and consumer perception of the risks of pesticide residues, and speculates where the future developments in these areas may lie.     

Assessing exposure to transformation products of soil-applied organic contaminants in surface water: comparison of model predictions and field data

Transformation products (TPs) of chemicals released to soil, for example, pesticides, are regularly detected in surface and groundwater with some TPs even dominating observed pesticide levels. Given the large number of TPs potentially formed in the environment, straightforward prioritization methods based on available data and simple, evaluative models are required to identify TPs with a high aquatic exposure potential. While different such methods exist, none of them has so far been systematically evaluated against field data. Using a dynamic multimedia, multispecies model for TP prioritization, we compared the predicted relative surface water exposure potential of pesticides and their TPs with experimental data for 16 pesticides and 46 TPs measured in a small river draining a Swiss agricultural catchment. Twenty TPs were determined quantitatively using solid-phase extraction liquid chromatography mass spectrometry (SPE-LC-MS/MS), whereas the remaining 26 TPs could only be detected qualitatively because of the lack of analytical reference standards. Accordingly, the two sets of TPs were used for quantitative and qualitative model evaluation, respectively. Quantitative comparison of predicted with measured surface water exposure ratios for 20 pairs of TPs and parent pesticides indicated agreement within a factor of 10, except for chloridazon-desphenyl and chloridazon-methyl-desphenyl. The latter two TPs were found to be present in elevated concentrations during baseflow conditions and in groundwater samples across Switzerland, pointing toward high concentrations in exfiltrating groundwater. A simple leaching relationship was shown to qualitatively agree with the observed baseflow concentrations and to thus be useful in identifying TPs for which the simple prioritization model might underestimate actual surface water concentrations. Application of the model to the 26 qualitatively analyzed TPs showed that most of those TPs categorized as exhibiting a high aquatic exposure potential could be confirmed to be present in the majority of water samples investigated. On the basis of these results, we propose a generally applicable, model-based approach to identify those TPs of soil-applied organic contaminants that exhibit a high aquatic exposure potential to prioritize them for higher-tier, experimental investigations.     

植物源农产品中农药残留降解技术研究进展

农药作为重要的农业生产资料,在保障农业生产率和农民增收等方面贡献显著。然而伴随农药使用量的增加,农药不合理、不规范使用造成的农药残留问题对人类健康、环境质量和农业可持续发展的影响不容忽视,农药残留降解技术是农产品降残降毒的一个重要研究领域。本文综述了目前植物源农产品中残留农药的降解技术研究概况,主要包括生物降解、物理降解、化学降解等技术。其中生物技术主要包括微生物降解、酶降解、基因工程菌降解以及植物调节因子辅助降解等,物理技术包括超声波降解、吸附去除、电离辐射以及冷等离子体降解等,化学技术则包括光化学降解、氧化分解以及电化学技术等,这些技术为解决农产品和环境中农药残留问题提供了科学基础和理论支撑。本文对上述技术的发展和应用前景进行了展望,为后续技术的优化和推广提供合理参考。     

Analytical methods for pesticide residue determination in bee products

Monitoring pesticide residues in honey, wax, and bees helps to assess the potential risk of these products to consumer health and gives information on the pesticide treatments that have been used on the field crops surrounding the hives. The present review seeks to discuss the basic principles and recent developments in pesticide analysis in bee products and their application in monitoring programs. Consideration is given to extraction, cleanup, chromatographic separation, and detection techniques.     

Effect of commercial processing on pesticide residues in orange products

The effect of commercial processing of orange juice on pesticide residues was investigated, and the processing factors of all orange products and by-products were also determined. The pesticide residues were strengthened using field trials and detected using Ultra-performance Liquid Chromatography-tandem Mass Spectrometry (UPLC-MS/MS). The results showed that the pesticide residues were mainly distributed in orange peels, the reduction of residue levels ranged from 43.6 to 85.4% during washing process. One percent to 4.5% of initial residues contained in the squeezed juice, 7–94.7% of the total relative residues were distributed in pomace. Filtrating could further reduce all the residue levels, ranging from 96.0–99.4% relative to unwashed whole fruits. After sterilization, there was only 0.5–3.1% of the residues contained in Not from Concentrate juice (NFC juice). 0.2–7.1% of the total relative residues was contained in concentrated juice, comparing with the filtrated juice; however, the concentration of cypermethrin and prochloraz was decreased, but the other 3 pesticides were increased. The residue levels of imidacloprid and carbendazim in orange oil were reduced but abamectin, prochloraz, and cypermethrin were concentrated, and the concentrated factor was 28.214, 5.232, and 5.621, respectively.     

Indicators for the exposure assessment of transformation products of organic micropollutants

Environmental transformation products of organic micropollutants have the potential to be similarly or even more mobile, persistent, ortoxic than their parent compounds. They should, therefore, be included in chemical hazard and risk assessment procedures as well as in the assessment of soil and water quality. To fulfill this requirement most efficiently, screening approaches that select relevant transformation products for detailed assessment are needed. This paper presents two process-based multimedia, multispecies models that allow us to quantitatively estimate the environmental fate of transformation products. The resulting exposure patterns are assessed with two indicators: joint persistence (JP), which describes the temporal extent of environmental exposure to a parent compound and its transformation products, and the predicted relative aquatic concentrations (RAC), which estimate the relative concentrations of parent compounds and their transformation products in surface water bodies. As a case study, JP and RAC are calculated for 16 pesticides and their relevant transformation products. The results for the JP indicator confirm the importance of considering transformation products in the assessment of overall persistence; for example, in the context of PBT assessments. Comparison of RAC results with monitoring data on herbicides and their transformation products shows the suitability of our approach for estimating relative concentrations in surface water, and as a consequence, its usefulness in identifying transformation products for future water quality monitoring programs. Transformation products of triketones and other highly used acidic herbicides are specifically identified as targets.     

物理技术降解农产品农药残留的研究进展

农药的使用对农业的发展发挥着重大作用,不仅可以使农产品保收、增产,还可以提升产品质量.但使用农药的同时也造成严重的农药污染以及食品安全问题.本文对可降低农产品中农药残留量的物理技术或方法进行了综述,包括光照、超声波、电离辐射、低温等离子体、超高压、洗涤、加热等,以期为相关技术的应用及提升、相关设备和产品的研发生产、农产品生产与消费安全的集成创新,提供理论依据,提高农产品食用安全性.     

Study of pesticide residues in agricultural products for the "Positive List" system

During a 3-year monitoring survey (April 2002-March 2005) of pesticide residues in agricultural products, 592 samples (324 domestic; 268 imported) collected in Hyogo prefecture, Japan were analyzed. The number of pesticides tested increased from 232 in FY 2002 to 323 in FY 2004. The purpose of the study was to clarify the residue status by accumulating information about pesticides detected frequently, to allow effective and efficient regulation under the new "Positive List" legislation to be implemented in FY 2006. Overall, 47% of domestic and 61% of imported samples contained detectable residues and ca. 60% of positive samples contained multiple residues. The limit of quantitation was set at 0.01 microg/g and the limit of detection was 0.001-0.003 microg/ g. Most of the residues were present at low concentrations: 80% of the detections in samples excluding imported citrus fruits were < 0.05 microg/g. More than 5 different pesticides (> 0.01 microg/g) were detected simultaneously in 13 samples. The sum of the ratios of residues to MRLs was calculated as one of the indexes to represent the risk of multiple residues, and they exceeded 100% in 3 imported frozen vegetables; baby kidney bean, spinach, Welsh onion. Samples in violation of the Food Sanitation Law were not found in our survey, but 1.9% of the samples might be in conflict with the new "Positive List" legislation.     

Persistent organochlorine pesticide residues in milk and dairy products in India

Monitoring of milk and dairy product samples of various brands from different cities in Maharashtra, India, was carried out to determine if there is any contamination due to organochlorine pesticide residues. The measurements were made using a gas chromatograph-electron capture detector system. Trace levels of DDT and HCH were detected in the samples. Total HCH levels in milk and milk product samples were lower than total DDT levels, which could be attributed to earlier extensive antimalaria sanitary activities. Butter had higher levels of DDT than cheese and milk powder. All levels of organochlorine pesticide residues in milk and milk products were well below the maximum permissible limits given by the FAO/WHO. More importantly, as compared with an earlier report, present levels of the contaminants are substantially lower, which indicate the gradual phase out of these compounds.     

Determination of seventeen pesticide residues in agricultural products by LC/MS

Residues of 17 pesticides in agricultural products were determined by LC/MS with an atmospheric pressure chemical ionization (APCI) interface in both positive and negative ion modes. Pesticides were extracted with acetonitrile, and the extracts were cleaned-up with a primary and secondary amine (PSA) mini-column eluted with acetone-hexane (1:1). Rice, orange and potato were spiked with the 17 pesticides at 0.1 microgram/g and analyzed by the proposed method. The average recoveries of these pesticides usually ranged from 70 to 98% and the relative standard deviations were usually around 10%. These results suggested that LC/MS with APCI could be used to determine the residue levels of the 17 pesticides in these crops.     

Recent advances in environmental risk assessment of transformation products

When micropollutants degrade in the environment, they may form persistent and toxic transformation products, which should be accounted for in the environmental risk assessment of the parent compounds. Transformation products have become a topic of interest not only with regard to their formation in the environment, but also during advanced water treatment processes, where disinfection byproducts can form from benign precursors. In addition, environmental risk assessment of human and veterinary pharmaceuticals requires inclusion of human metabolites as most pharmaceuticals are not excreted into wastewater in their original form, but are extensively metabolized. All three areas have developed their independent approaches to assess the risk associated with transformation product formation including hazard identification, exposure assessment, hazard assessment including dose-response characterization, and risk characterization. This review provides an overview and defines a link among those areas, emphasizing commonalities and encouraging a common approach. We distinguish among approaches to assess transformation products of individual pollutants that are undergoing a particular transformation process, e.g., biotransformation or (photo)oxidation, and approaches with the goal of prioritizing transformation products in terms of their contribution to environmental risk. We classify existing approaches for transformation product assessment in degradation studies as exposure- or effect-driven. In the exposure-driven approach, transformation products are identified and quantified by chemical analysis followed by effect assessment. In the effect-driven approach, a reaction mixture undergoes toxicity testing. If the decrease in toxicity parallels the decrease of parent compound concentration, the transformation products are considered to be irrelevant, and only when toxicity increases or the decrease is not proportional to the parent compound concentration are the TPs identified. For prioritization of transformation products in terms of their contribution to overall environmental risk, we integrate existing research into a coherent model-based, risk-driven framework. In the proposed framework, read-across from data of the parent compound to the transformation products is emphasized, but limitations to this approach are also discussed. Most prominently, we demonstrate how effect data for parent compounds can be used in combination with analysis of toxicophore structures and bioconcentration potential to facilitate transformation product effect assessment.     

通过织机技术改造开发新型织物的实践

介绍了开发新产品的一种思路,通过对织机的技术改造来开发新产品。织机技术改造包括:使织机的卷取机构具有微机控制卷取速度的功能,引纬机构具有临时不引纬的功能,钢筘具有上下移动的功能。织机经过技术改造后,可以生产出可变化经纬密的织物,例如开发生产出具有曲线效果的变化斜纹织物、透孔织物、波形织物等新型织物,可以为企业新产品开发提供有意义的参考。     

拉曼光谱技术在农产品药物残留检测中的应用

近年来,农产品药物残留超标引发了一系列食品安全问题,为了保障国家食品安全、保护消费者健康,需要对农产品中的药物残留进行定性定量检测。表面增强拉曼散射技术 (Surface-enhanced Raman scattering , SERS) 是一种极具吸引力的工具,可用于高效检测农药残留。本文介绍了表面增强拉曼光谱检测技术的概况,简介了拉曼增强基底,分析了表面增强拉曼光谱技术在药物标准溶液、农产品(肉类、水产品、果蔬和其他部分农产品等)药物残留检测领域中的研究现状,并针对当前农产品药物残留检测的发展趋势进行前景展望。     

农产品中农药残留检测前处理方法的研究进展

世界上农药年产量高于200万吨, 有1000多种人工合成化合物被用作杀虫剂、杀藻剂、除虫剂、杀菌剂、落叶剂等农药。有机农药的大量施用会造成严重的污染问题, 并对人体健康造成严重威胁。因此, 建立简单、高效和成本低的农药残留快速检测方法非常重要。由于农残检测涉及的样品种类繁多、样品组成复杂和样品形态多变, 这对农残检测造成的干扰增加, 所以需要选择和改进农药残留检测的前处理方法。科研人员在农药残留快速检测技术方面做了大量的研究, 并取得了较大的进步。本文介绍了该领域一些热点技术的研究方法和动态, 并对存在问题进行了分析, 以期为农药残留快速检测的深入研究提供参考。     

Survey of pesticide residues in imported cereal products (1994.4 approximately 2006.3)

A survey of pesticide residues in 490 imported cereal products on the Tokyo market from April 1994 to March 2006 was carried out. Eight kinds of organophosphorus pesticides (chlorpyrifos, chlorpyrifos-methyl, DDVP, diazinon, etrimfos, malathion, MEP and pirimiphos-methyl) were detected at levels between Tr (below 0.01 ppm) and 0.82 ppm from 91 samples.In our investigations, chlorpyrifos-methyl and malathion tended to be detected in samples from America, pirimiphos-methyl in those from Europe, and MEP in those from Oceania. Thus, pesticide residues seemed to be different in produce from different areas.Residue levels of these pesticides were calculated as between 0.08 and 13.2% of their ADI values according to the daily intake of cereal products. Therefore, these cereal products should be safe for normal usage.     

农产品和水体中农药残留检测技术研究进展

农药残留是指由于使用农药而残留于农作物、水体、土壤等的农药原体和代谢物。农药具有毒性强、稳定性好、生物聚集性等特点,极易在环境中发生富集,最终进入人体,其残留问题已对人类健康和环境中其他生物体形成极大威胁。因此监测食品或环境中的农药残留水平对人类健康和保护生物多样性具有十分重要的作用。随着科学技术的不断探索和发展,农药残留检测技术也取得了重大突破。本研究总结了农药残留的方式和危害;分析了农药残留检测中常用的前处理方法(液液萃取、固相萃取、QuEChERS提取法和其他方法),对比了几种方法的优缺点;对近年来农药残留的传统分析技术的最新应用和新型的检测分析技术及其应用进行了综述,并对当前领域存在的问题和未来的发展方向进行了总结。