李晓贝^,, 赵晓燕^,, 李健英, 陈磊, 周昌艳, 何香伟上海市农业科学院农产品质量标准与检测技术研究所,上海201403

Residue Behavior and Dietary Intake Risk Assessment of Imidaclothiz in Pakchoi (Brassica chinensis L.)

LI XiaoBei^,, ZHAO XiaoYan^,, LI JianYing, CHEN Lei, ZHOU ChangYan, HE XiangWeiInstitute for Agri-Food Standards and Testing Technology, Shanghai Academy of Agricultural Sciences, Shanghai 201403

通讯作者: 赵晓燕,Tel：021-67131635;E-mail：cindy8119@163.com

责任编辑: 赵伶俐
收稿日期:2019-12-17接受日期:2020-03-11网络出版日期:2020-09-01

基金资助:

上海市农委科技兴农推广项目.沪农科推字2017第4-3号

Received:2019-12-17Accepted:2020-03-11Online:2020-09-01
作者简介 About authors
李晓贝,Tel：021-67131635;E-mail：lixiaobei212@sina.com。








摘要
【目的】明确氯噻啉在青菜上的残留特性,为制定氯噻啉在青菜上的安全使用标准提供科学依据。【方法】于上海市松江区进行10%氯噻啉可湿性粉剂在冬季与夏季不同生长季节及露地与大棚不同种植环境下的青菜上的残留试验,其中残留消解动态试验以90 g（a.i.）·hm^-2（最高推荐剂量的1.5倍）的剂量施用1次,施药后0（2 h）、1、2、3、4、5、7、10、14、21和30 d连续采集青菜样品检测氯噻啉残留量;最终残留试验以60 g（a.i.）·hm^-2（最高推荐剂量）和高剂量90 g（a.i.）·hm^-2（最高推荐剂量的1.5倍）两个施药浓度,间隔7 d,施药2—3次,分别于最后一次施药后3、5和7 d采集青菜样品检测氯噻啉残留量。利用QuEChERS前处理方法对青菜中的氯噻啉残留进行提取净化,通过超高效液相色谱–串联质谱法检测氯噻啉在青菜上的残留量。基于最终残留试验结果及青菜的膳食消费量,应用风险商对青菜中氯噻啉残留量进行风险描述,以氯噻啉每日允许摄入量为标准对不同人群的膳食摄入风险进行评估,涵盖未成年男女（3—6岁幼儿及7—19岁儿童青少年）和成年男女（20—59成年人及60—69岁老年人）8类人群。【结果】在0.01—1.0 mg·kg^-1的添加浓度范围内,氯噻啉在青菜中的添加回收率为77.2%—87.9%,相对标准偏差为2.5%—3.0%,检出限为0.0002 mg·kg^-1,定量限为0.01 mg·kg^-1,可满足检测需求。残留试验结果显示：10%氯噻啉可湿性粉剂以90 g（a.i.）·hm^-2的施药剂量在青菜上的降解趋势符合一级动力学方程,在冬季大棚、夏季大棚及夏季露地青菜上的消解动态方程分别为C=0.8476e^-0.158t、C=1.6558e^-0.212t、C=4.3069e^-1.197t,半衰期分别为4.39、3.27和0.58 d,消解时间及种植条件均对氯噻啉在青菜上的消解效率有显著影响(P<0.05);以60 g（a.i.）·hm^-2和90 g（a.i.）·hm^-2的施药剂量在青菜上间隔7 d喷雾2—3次,最后一次施药7 d后冬季大棚内青菜上氯噻啉最终残留量低于0.5 mg·kg^-1,最后一次施药3 d后夏季露地及大棚青菜上氯噻啉最终残留量均低于0.5 mg·kg^-1,最终残留量与施药浓度基本成正相关,与施药次数无显著相关性(P>0.05)。膳食摄入风险评估结果显示：各类人群通过青菜摄入氯噻啉的风险商最大值为0.2196,远低于1。【结论】氯噻啉属易降解农药,夏季青菜中氯噻啉消解速率高于冬季,露地高于大棚。中国普通居民由青菜摄入氯噻啉的风险较低,慢性摄入风险均可接受。因此,在推荐使用浓度下（45—60 g（a.i.）·hm^-2）间隔7 d施用,最多施用3次,安全间隔期夏季3 d、冬季7 d,氯噻啉可安全有效地用于青菜虫害防治。
关键词： 青菜;氯噻啉;残留;大棚;露地;风险评估

Abstract
【Objective】The objective of the experiment was to reveal the residue behavior of imidaclothiz in pakchoi (Brassica chinensis L.), so as to provide a scientific basis for its safety utilization.【Method】Field experiments of 10 % imidaclothiz wettable powder in pakchoi under open field and greenhouse conditions were carried out in winter (between November and December) of 2018 and summer (between July and August) of 2019 at Shanghai. In dissipation experiments, the dosage of imidaclothiz was 90 g (a.i.)·hm^-2(1.5 times recommended dosage) with one-time spray, and the treated samples were collected randomly from several points of each plot at 2 h, 1, 2, 3, 4, 5, 7, 10, 14, 21, and 30 days after spraying of the pesticide to detect the residual concentration. For the study of final residue of imidaclothiz in pakchoi, imidaclothiz was sprayed for 2-3 times at an internal of 7 days at the recommended dosage (60 g (a.i.)·hm^-2) and 1.5 times recommended dosage (90 g (a.i.)·hm^-2), and the treated samples were collected randomly at 3, 5, and 7 days after the final processing to detect the residual concentration. The QuEChERS method coupled with ultra-high performance liquid chromatography-tandem mass spectrum (UPLC-MS/MS) was used to determine imidaclothiz in pakchoi. Dietary intake risk assessments were processed based on the maximal concentration, acceptable daily intake (ADI) of imidaclothiz, and daily consumption of pakchoi. The people involved in the experiment were divided into 8 classes, including underage male and female (subdivided into 3-6 years old infants and 7- 19 years old teenagers), as well as adult male and female (subdivided into 20-59 years old adults and 60-69 years old elder crowed).【Result】The limit of detection (LOD) of imidaclothiz was 0.0002 mg·kg^-1, and the limit of quantitation (LOQ) was 0.01 mg·kg^-1. Recoveries of imidaclothiz in pakchoi ranged from 77.2% to 87.9% at 0.01, 0.10 and 1.0 mg·kg^-1spiked levels, respectively, and the relative standard deviations (RSDs) were in the range of 2.5%-3.0%. The developed analytical method was suitable for the determination of imidaclothiz in pakchoi. Field experiments showed that the dissipation dynamics of imidaclothiz sprayed at the dosage of 90 g (a.i.)·hm^-2in pakchoi exhibited a first-order kinetic decline. The regression equation of imidaclothiz in winter greenhouse, summer greenhouse and summer open fields were C=0.8476e^-0.158t, C=1.6558e^-0.212t and C=4.3069e^-1.197t, and their half-lives were 4.39, 3.27 and 0.58 days, respectively. Both existing time and plant conditions had significant correlation with degradation efficiency of imidaclothiz in pakchoi (P<0.05). The maximal concentrations of imidaclothiz in pakchoi under winter greenhouse were all below 0.5 mg·kg^-1 at 7 days after the final processing, when it was sprayed for 2-3 times at an internal of 7 days at the dosage of 60 or 90 g (a.i.)·hm^-2 in pakchoi, while it just required 3 days to decline below 0.5 mg·kg^-1 for those treated in summer in the same place, regardless of greenhouse and open fields. The final residue concentrations had positive correlation with spraying dosage, but no relationship with spraying number (P>0.05). The risk assessments showed that hazard quotients (HQs) of imidaclothiz for different groups consuming pakchoi were far below 1, and the maximum HQ was 0.2196.【Conclusion】Imidaclothiz was a kind of easily degradable pesticide, and its degradation rate was significantly higher in summer than winter, as well as higher in open fields than greenhouse. The dietary exposure of imidaclothiz only by pakchoi’s consumption was at a relatively low level to the ordinary resident of China. Generally, it’s effective to use imidaclothiz as the pest control method for pakchoi, accompanied with recommended dosage (45-60 g (a.i.)·hm^-2) and appropriate pre- harvest intervals (7 days in winter and 3 days in summer).
Keywords：pakchoi;imidaclothiz;residue;greenhouse;open field;risk assessment


PDF (496KB)元数据多维度评价相关文章导出EndNote|Ris|Bibtex收藏本文
本文引用格式
李晓贝, 赵晓燕, 李健英, 陈磊, 周昌艳, 何香伟. 氯噻啉在青菜上的残留特性及其膳食摄入风险评估[J]. 中国农业科学, 2020, 53(17): 3587-3596 doi:10.3864/j.issn.0578-1752.2020.17.015
LI XiaoBei, ZHAO XiaoYan, LI JianYing, CHEN Lei, ZHOU ChangYan, HE XiangWei. Residue Behavior and Dietary Intake Risk Assessment of Imidaclothiz in Pakchoi (Brassica chinensis L.)[J]. Scientia Acricultura Sinica, 2020, 53(17): 3587-3596 doi:10.3864/j.issn.0578-1752.2020.17.015

0 引言

【研究意义】以吡虫啉为代表的新烟碱类杀虫剂对蚜虫、粉虱、鳞翅目及部分鞘翅目等害虫有较强的触杀和内吸活性,因其高效、广谱、低毒、选择性强、环境相容性良好等优点,已广泛应用于水稻、瓜菜等作物种植过程中的虫害防治,以取代部分毒性较高的有机磷、有机氯、氨基甲酸酯等杀虫剂^[1,2]。但是随着吡虫啉使用范围的扩张及使用频率的逐步增强,抗性问题日益突出,新型药剂的研发生产与安全应用工作已于国际范围内开展。【前人研究进展】氯噻啉（Imidaclothiz）是我国自主研发并正式登记的3种新烟碱类杀虫剂之一（另两种为环氧虫啶及哌虫啶）^[3,4,5],具备新烟碱类农药广谱、低毒等共性的同时具有更强的内吸活性,其活性是啶虫脒、吡虫啉等一般新烟碱类农药的20倍,并克服了在低温时防效差的缺点,而且由于尚未大范围使用,害虫抗药性较低^[6]。氯噻啉是一种硝基胍噻唑类杀虫剂,主要作用于烟酸乙酰胆碱酯酶受体（nicotinic acetylcholinereceptors,nAChRs）,通过与昆虫神经系统中的相应受体竞争性结合对其选择性抑制,从而干扰害虫运动神经系统的信号传递,使其中枢神经正常传导受阻而麻痹死亡^[7,8]。氯噻啉原药对大鼠急性经口LD₅₀为雌性1 620 mg·kg^-1,雄性1 470 mg·kg^-1,对雌、雄大鼠急性经皮LD₅₀均大于2 000 mg·kg^-1,属低毒农药^[9]。江苏省南通江山农药化工股份有限公司已获得氯噻啉原药、10%可湿性粉剂及40%水分散粒剂在国内的登记,主要用于水稻烟飞虱、茶树小绿叶蝉、番茄白粉虱、甘蓝、柑橘树、小麦及烟草蚜虫的防治^[4]。上海市农业委员会蔬菜办公室统计显示,2017年上海市蔬菜总播种面积9.47万hm²,总上市量2.816×10⁶ t,其中绿叶类蔬菜148.9万t,占比达52.8%^[10],且2019年5—7月上海市郊区蔬菜播种面积排名前二的始终为青菜（Brassica chinensis L.）及鸡毛菜^[11]。青菜上主要虫害为蚜虫、叶蛾、跳甲、粉虱等^[12,13],但是尚无直接登记在青菜上可用于防治粉虱的农药。前期药效试验显示10%氯噻啉可湿性粉剂对青菜烟粉虱防效良好,药后7 d防效为82.9%—85.7%,对作物安全。目前已开展氯噻啉残留特性研究的作物主要为烟叶、水稻、萝卜、小麦、柑橘、甘蓝等^{[14,15,16,17,18]},其在青菜上的残留特性尚未见报道,缺乏相应的使用准则（good agricultural practices,GAP）。噻虫嗪、啶虫脒、氯氰菊酯等农药在大棚及露地青菜及吡蚜酮在大棚及露地芥蓝上的残留试验显示不同生产环境中农药的降解速率存在显著差异^[19,20,21]。【本研究切入点】由于国内外尚未制定氯噻啉在青菜上的最大残留限量值（maximum residue limit,MRL）,青菜上氯噻啉残留的安全性研究亦属空白。【拟解决的关键问题】上海地区大棚及露地青菜均有种植,且四季均可生产。本研究于2018—2019年在上海市松江区进行10%氯噻啉可湿性粉剂在冬季与夏季不同生长季节及露地与大棚不同种植环境下青菜上的残留试验,并对其膳食摄入风险进行评估,为明确氯噻啉在青菜上的残留特性,并为制定氯噻啉在青菜上的安全使用标准提供科学依据,

1 材料与方法

田间试验于2018年11—12月（大棚）及2019年7—8月（大棚和露地同时进行）在上海松江区新浜镇（37°56′2.29″ N,121°4′4.14″ E）进行,分别研究冬季与夏季不同生长季节及露地与大棚不同生长环境下氯噻啉在青菜上的最终残留量和消解动态。上海属于典型的亚热带季风性湿润气候,夏季高温多雨,冬季低温少雨,2018年11—12月日气温为0—23℃,2019年7—8月日气温为20—37℃。试验地土壤类型为壤土,有机质含量为3.3%,阳离子代换量为19.04 cmol·L^-1。各小区栽培条件一致。

1.1 材料与试剂

10%氯噻啉可湿性粉剂购自江苏省南通江山农药化工股份有限公司;氯噻啉标准品（纯度95.0%）,购自德国Ehrenstorfer公司（Dr. Ehrenstorfer GmbH）;甲醇、乙腈（均为色谱级）购自上海安谱公司;甲酸（优级纯）购自美国安捷伦公司;提取盐包（4 g MgSO₄、1 g NaCl、1 g TSCD、0.5 g DHS）及SinCHERS固相萃取柱（400 mg C18、100 mg GCB、200 mg BIPH、1 400 mg MgSO₄）购自上海润蒽珀;Waters 120 -C18色谱柱（美国Waters公司）。

1.2 仪器与设备

Triple Quad^TM 5500液相色谱-串联质谱仪（Waters UPLC+AB 5500）;Sorval ST 16R高速离心机（美国Thermo Fisher公司）;EOFO-945205涡旋仪（美国Talboys公司）;超纯水仪（英国ELGA PureLab公司）;前处理电动工具（天津安邦键合科技有限公司）;998B全营养破壁料理机（欧斯麦电器集团（香港）实业有限公司）。

1.3 农药残留田间试验

所用农药为10%氯噻啉可湿性粉剂（推荐使用剂量为有效成分45—60 g (a.i.)·hm^-2）,青菜品种均为‘华王’。参照农药残留试验准则要求设置试验小区,每个处理小区面积为15 m²,设3次重复,小区间设保护带,另设1个空白对照小区^[22]。在同一生产基地,于2018年冬季大棚及2019年夏季大棚和露地青菜上施用同种药剂,在相同施药浓度、施药次数及同一采收间隔期等条件下进行比对试验。在各试验小区内随机采集正常生长的青菜,每次每个小区采集1 kg以上样本,并去除腐坏、萎蔫、枯老的茎叶,采集后匀浆装瓶,并置于-20℃冰箱中贮存待测。

1.3.1 残留消解动态试验 10%氯噻啉可湿性粉剂以90 g（a.i.）·hm^-2（最高推荐剂量的1.5倍）的剂量施用1次,施药后0（2 h）、1、2、3、4、5、7、10、14、21和30 d连续采集青菜样品,测定青菜中氯噻啉残留量。

1.3.2 最终残留试验 10%氯噻啉可湿性粉剂以低剂量60 g（a.i）·hm^-2（最高推荐剂量）和高剂量90 g（a.i）·hm^-2（最高推荐剂量的1.5倍）两个施药浓度,分别施药2次、3次,施药间隔期7 d。分别于最后一次施药3、5和7 d后采集青菜样品,测定青菜中氯噻啉残留量。

1.4 农药残留检测方法

1.4.1 样品前处理提取：称取（10±0.05）g匀浆后的样品置于50 mL离心管中,放入-20℃冰箱预冷20—30 min。加入10 mL乙腈,手摇快速振荡约30 s后加入提取盐包,手摇快速振荡混匀约1 min后于室温下4 000 r/min离心5 min。净化：将SinCHERS固相萃取柱插入离心管中,以1 mm·s^-1左右的速度缓慢下压使离心管内的上层有机提取液穿过阻水滤片接触到净化填料,通过净化填料将有机提取液内溶解的杂质吸附后进入到储液槽内,继续下压SinChERS柱体至无法下行位置止,取柱内净化后的有机相根据实际情况适当稀释,涡旋混匀后过0.22 μm的滤膜,装入进样小瓶中进行LC-MS/MS分析。

1.4.2 分析测定条件 色谱条件：Waters 120-C18色谱柱（100 mm×2.1 mm,1.7 μm）;柱温为40℃;进样量为3 μL;梯度洗脱条件如表1所示。

Table 1
表1
表1梯度洗脱程序
Table 1Procedure of gradient elution

时间 Time (min)	流速 Flow velocity (mL·min-1)	流动相 Mobile phase
		V甲醇 Methyl alcohol (%)	V 0.1%甲酸水 0.1% Formic acid in water (%)
0.0	0.35	30	70
1.0	0.35	30	70
2.5	0.35	90	10
3.0	0.35	30	70
4.0	0.35	30	70

新窗口打开|下载CSV

质谱条件：电喷雾离子源（electrospray ionization,ESI）;正离子模式;毛细管电压为5 500 V;雾化气压力为38 psi;碰撞气为氩气;鞘气温度为500℃;鞘气流速为50 L·min^-1;检测方式为多重反应监测（multiple reaction monitoring,MRM）,氯噻啉的质谱参数如表2所示。

Table 2
表2
表2氯噻啉的质谱参数
Table 2Mass spectrum parameters of imidaclothiz

农药名称 Pesticide	保留时间 Retention time (min)	定量离子对 Quantitative ions (m·z-1)	定性离子对 Qualitative ion (m·z-1)	碰撞电压 Collision pressure (V)	碰撞能量 Collision energy (eV)
氯噻啉 Imidaclothiz	2.12	262.2/181.1	262.2/181.1	100	20 28
			262.2/122.1	100

新窗口打开|下载CSV

1.5 膳食暴露评估

1.5.1 膳食暴露评估 膳食暴露量主要用来评估计算可能接触的暴露途径及剂量水平,明确实际与预期暴露的剂量水平及可能受危害的敏感人群。应用风险商（hazard quotient,HQ）对青菜中氯噻啉残留量进行风险描述,以氯噻啉每日允许摄入量（acceptable daily intake,ADI）为标准进行评价,通过接触人群的氯噻啉膳食暴露量与氯噻啉每日允许摄入量计算风险商HQ^[23],以表征经青菜途径摄入氯噻啉的风险大小,如公式（1）所示。当HQ<1时,表示没有风险;当HQ>1时,表明有风险,且数值越大,风险也越大。

（1）$\text{HQ}=\frac{EED}{ADI}=\frac{C\times FI}{BW\times ADI}$
式中,EED（estimated exposure dose）为通过青菜摄入氯噻啉的日估计暴露量（mg·kg^-1·bw^-1·d^-1）,ADI为每日允许摄入量（mg·kg^-1·bw^-1·d^-1）,C（residue concentration）为试验中获得的青菜中氯噻啉残留量（mg·kg^-1）,FI（food intake）为人体每日食物摄入量（kg·d^-1）,BW（body weight）为居民平均体重（kg）。

1.5.2 风险评估数据来源 （1）青菜中氯噻啉残留量（C）：采用最终残留试验测定数据,本研究中采用试验测得最大残留量。（2）居民体重BW及青菜膳食消费数据（FI）：体重采用国家体育总局发布的《2014年国民体质监测公报》中不同年龄及性别人群的体重数据^[24],消费数据由上海地区居民膳食调查计算,采用小白菜的消费数据,详见表3。膳食调研以整样随机抽样的方法进行抽样,并使用问卷调查进行个人膳食数据搜集,以24 h膳食回顾法作为食物摄入量调查方法。调研覆盖上海市徐汇、虹口、青浦、宝山及浦东新区5个区共2 453人,每人次1季度调研1次,每个人次样本持续跟踪4个季度后,按照4个季度的平均值作为最终膳食数据。（3）氯噻啉每日允许摄入量（ADI）：采用GB 2763-2019的数据,氯噻啉的ADI值为0.025 mg·kg^-1·bw^-1·d^-1[25]。

Table 3
表3
表3不同人群的体重和青菜摄入量
Table 3Body weight of the subpopulation and dietary intake of pakchoi

人群类别 Subpopulation	平均体重 Body weight (kg)	调研人群数量 Number of investigated groups	小白菜日均摄入量 Daily intake of pakchoi (kg·d-1)	蔬菜日均摄入量 Daily intake of vegetable (kg·d-1)
3—6岁男性Male age 3-6	19.6	50	0.066	0.266
3—6岁女性Female age 3-6	18.7	43	0.061	0.213
7—19岁男性Male age 7-19	48.9	365	0.071	0.294
7—19岁女性Female age 7-19	43.5	360	0.074	0.299
20—59岁男性Male age 20-59	70.3	646	0.074	0.279
20—59岁女性Female age 20-59	57.8	722	0.069	0.263
60—69岁男性Male age 60-69	67.1	132	0.062	0.252
60—69岁女性Female age 60-69	59.5	135	0.063	0.247

新窗口打开|下载CSV

1.6 数据分析

所得数据由IBM SPSS Statistics 19软件通过一般线性模型单变量多因素方差分析（General Linear Model- Univariate,GLM-Univariate）进行显著性分析,分析方法为邓肯氏多重范围检验（Duncan’s multiple range tests）,显著性水平为P<0.05。

2 结果

2.1 方法的线性范围、回收率、精密度、检出限及定量限

将1 mg·L^-1的氯噻啉标准溶液用空白基质提取液稀释配制1、2.5、10、25和50 μg·L^-1系列标准溶液。以标准溶液的浓度为横坐标（x）,相应峰面积的丰度值为纵坐标（y）绘制标准曲线,在1—50 μg·L^-1的线性范围内,标准曲线的回归方程为：y=38196x+32161,线性回归系数R²为0.9998。

在青菜空白样品中,添加0.01、0.1和1.0 mg·kg^-1 3个浓度水平的氯噻啉标准溶液,进行添加回收率试验,每个添加浓度重复5次,考察方法的精密度。以3倍信噪比（S/N=3）计算方法的检出限（limit of detection,LOD）,满足添加回收率范围及相对标准偏差（relative standard deviation,RSD）的最低添加浓度为定量限（limit of quantitation,LOQ）^[26],各化合物的添加回收率及定量限、检出限列于表4。在0.01—1.0 mg·kg^-1的添加浓度范围内,氯噻啉在青菜中的添加回收率为77.2%—87.9%,RSD为2.5%—3.0%,可满足检测需求。

Table 4
表4
表4方法的添加回收率、检出限（LOD）及定量限（LOQ）（n=5）
Table 4Recovery, limit of detection (LOD) and limit of quantitation (LOQ) (n=5) under different fortified concentrations

添加浓度 Fortified concentration (mg·kg-1)	回收率Recovery rate (%)						相对标准偏差 RSD (%)	检出限 LOD (mg·kg-1)	定量限 LOQ (mg·kg-1)
	1	2	3	4	5	平均值 Mean
0.01	84.0	86.8	80.0	86.8	82.0	83.9	3.0	0.0002	0.01
0.10	82.9	81.2	83.5	80.2	77.2	81.0	2.5
1.00	87.9	86.0	82.2	82.3	82.8	84.2	2.6

新窗口打开|下载CSV

2.2 氯噻啉在青菜上的残留消解动态

图1显示,以10%氯噻啉可湿性粉剂90 g(a.i)·hm^-2的施药剂量在青菜上喷雾1次,不同种植环境下氯噻啉在青菜上的残留量均随时间延长逐渐降低,且降解趋势符合一级动力学方程C_t=C₀e^-kt（表5）,式中C_t为氯噻啉随时间变化的残留量,t为施药后天数,k为消解速率常数,消解半衰期T_1/2=ln2/k。氯噻啉在冬季大棚、夏季大棚及夏季露地的原始沉积量（药后2 h残留量）平均值分别为2.322、2.444和2.178 mg·kg^-1,消解半衰期分别为4.39、3.27和0.58 d,属于易降解农药。整体上,氯噻啉在不同种植季节及种植环境的青菜中原始沉积量无显著差异,冬季青菜中氯噻啉半衰期长于夏季,大棚青菜中氯噻啉半衰期长于露地。通过SPSS软件对残留数据进行GLM多因素方差分析（P<0.05）,主体间效应检验结果显示消解时间及种植条件的P值均小于0.05,表明二者对氯噻啉在青菜上的消解残留均有显著影响。种植条件的两两比较结果也显示冬季、夏季氯噻啉的消解残留量有显著差异,露地氯噻啉消解速率显著高于大棚。但因采样及样品前处理允许误差,导致部分结果存在一定偏差（表6）。

图1

新窗口打开|下载原图ZIP|生成PPT
图1不同种植环境下氯噻啉在青菜中的残留消解动态曲线

Fig. 1Residue dynamics of imidaclothiz in pakchoi under different planting environments



Table 5
表5
表5氯噻啉在青菜中残留消解动态回归方程及相关参数
Table 5Regression equation and relevant parameters of degradation dynamics of imidaclothiz in pakchoi

试验条件 Experimental condition	消解动态方程 Linear equation of degradation dynamics	相关系数 R2	半衰期 T1/2 (d)
大棚/冬 Greenhouse in winter	C=0.8476e-0.158t	0.8504	4.39
大棚/夏 Greenhouse in summer	C=1.6558e-0.212t	0.9739	3.27
露地/夏 Open fields in summer	C=4.3069e-1.197t	0.9553	0.58

新窗口打开|下载CSV

Table 6
表6
表6影响动态残留的主体间效应检验结果
Table 6Tests of between-subject effects for degradation dynamics of imidaclothiz

源 Source	III型平方和 Type III sum of square	自由度 df	均方 Mean square	F检验 F	显著性 Significance
校正模型 Corrected model	49.36a	12	4.113	95.21	0.000
截距 Intercept	29.83	1	29.83	690.4	0.000
种植条件 Plant conditions	1.196	2	0.5980	13.84	0.000
时间 Time	48.16	10	4.816	111.5	0.000
误差 Error	3.716	86	0.0430
总计 Total	82.90	99
校正的总计 Corrected total	53.08	98

^a：R²=0.930（调整R²=0.920）
^a: R²=0.930 (Adjusted R²=0.920)

新窗口打开|下载CSV

2.3 氯噻啉在青菜中最终残留量

末次施药3 d后,冬季大棚、夏季大棚及夏季露地青菜中氯噻啉的最大残留量分别为1.633、0.283和0.269 mg·kg^-1（每个试验水平取3个平行小区的最大值,下同）;末次施药5 d后,冬季大棚、夏季大棚及夏季露地青菜中氯噻啉的最大残留量分别为1.110、0.214和0.120 mg·kg^-1;末次施药7 d后,冬季大棚、夏季大棚及夏季露地青菜中氯噻啉的最大残留量分别为0.739、0.153和0.035 mg·kg^-1（表7）。主体间效应hb检验结果显示种植条件、施药浓度及采收间隔期均对氯噻啉的最终残留量有显著影响,施药次数无显著影响（表8）。两年的残留试验数据表明,残留量与施药浓度基本成正相关,即随着氯噻啉施药浓度的增加残留量上升,而随采收间隔的延长而残留量逐渐降低,与施药次数无相关性。冬季氯噻啉的最终残留量显著高于夏季,大棚显著高于露地,与消解动态规律相符。

Table 7
表7
表7氯噻啉在青菜中的最终残留量
Table 7Final residue of imidaclothiz in pakchoi

施药剂量 Application concentration (g (a.i.)· hm-2)	施药次数 Application no.	采收距末次施药间隔时间 Days after the last treatment (d)	氯噻啉残留量Residue (mg·kg-1)
			大棚（冬季） Greenhouse in winter	大棚（夏季） Greenhouse in summer	露地（夏季） Open fields in summer
60	2	3	0.849±0.293	0.188±0.042	0.203±0.073
		5	0.416±0.101	0.082±0.028	0.050±0.016
		7	0.276±0.056	0.046±0.006	0.011±0.002
	3	3	0.621±0.188	0.166±0.039	0.199±0.064
		5	0.468±0.076	0.087±0.025	0.045±0.012
		7	0.206±0.040	0.046±0.002	0.026±0.009
90	2	3	1.166±0.352	0.248±0.035	0.246±0.043
		5	0.893±0.439	0.147±0.060	0.084±0.013
		7	0.476±0.149	0.112±0.004	0.027±0.002
	3	3	1.103±0.467	0.226±0.036	0.264±0.017
		5	0.824±0.254	0.128±0.034	0.084±0.032
		7	0.489±0.227	0.113±0.041	0.024±0.006

新窗口打开|下载CSV

Table 8
表8
表8影响氯噻啉最终残留的主体间效应检验结果
Table 8Tests of between- subject effects for degradation dynamics of imidaclothiz

源 Source	III 型平方和 Type III sum of square	自由度df	均方 Mean square	F检验 F	显著性 Significance
校正模型 Corrected model	12.19a	6	2.031	87.23	0.000
截距 Intercept	11.69	1	11.69	502.2	0.000
种植条件 Plant conditions	9.566	2	4.783	205.4	0.000
施药浓度 Spraying dosage	0.480	1	0.480	20.60	0.000
施药次数 Spraying number	0.00001	1	0.00001	0.000	0.983
采收间隔期 Pre-harvest interval	2.141	2	1.070	45.98	0.000
误差 Error	2.352	101	0.023
总计 Total	26.23	108
校正的总计 Corrected total	14.54	107

^a：R²=0.838（调整R²=0.829）
^a: R²=0.838 (Adjusted R²=0.829)

新窗口打开|下载CSV

2.4 膳食摄入风险评估

膳食评估结果显示青菜中氯噻啉残留对8类人群的风险商（HQ）均远小于1,未成年人群风险相对高于成年人群,慢性摄入风险均可接受（表9）。

Table 9
表9
表9青菜生长期使用氯噻啉的膳食暴露量和风险商
Table 9Dietary exposure and hazard quotient of imidaclothiz in pakchoi

人群类别 Subpopulation	估计暴露量EED (mg·kg-1·bw-1·d-1)			风险商RQ
	3 d	5 d	7 d	3 d	5 d	7 d
3—6岁男性 Male age 3-6	0.0055	0.0037	0.0025	0.2196	0.1492	0.0994
3—6岁女性 Female age 3-6	0.0053	0.0036	0.0024	0.2139	0.1454	0.0968
7—19岁男性 Male age 7-19	0.0024	0.0016	0.0011	0.0944	0.0642	0.0427
7—19岁女性 Female age 7-19	0.0028	0.0019	0.0013	0.1111	0.0755	0.0503
20—59岁男性 Male age 20-59	0.0017	0.0012	0.0008	0.0683	0.0464	0.0309
20—59岁女性 Female age 20-59	0.0019	0.0013	0.0009	0.0777	0.0528	0.0352
60—69岁男性 Male age 60-69	0.0015	0.0010	0.0007	0.0603	0.0410	0.0273
60—69岁女性 Female age 60-69	0.0017	0.0012	0.0008	0.0696	0.0473	0.0315

新窗口打开|下载CSV

3 讨论

3.1 不同种植条件下氯噻啉在青菜上的残留特性分析

影响农药在环境中降解行为的主导因素为光、热等物理化学因素及土壤中微生物、植物等生物因素,对于同种作物,在土壤环境相似的情况下,水解、光解等物化因素是引起农药在环境中消解效率差异的主要因素^[27]。氯噻啉光解的发生途径主要有两个,一是在咪唑烷上发生光氧化生成羰基后脱去硝基,二是直接脱去硝基后将咪唑烷上所带的C=N氧化为C=O,光解作用符合一级动力学反应规律,其在太阳光下纯净水中的光解半衰期为6.71 h,具有中等的光降解特性^[17]。有研究显示温度的升高可促进氯噻啉的降解^[26],可以推断夏季的高温及强光照是其降解速率高于冬季的主要原因。露地环境由于开阔无遮拦具有更强的直射光照,空气流动性更强,且夏季雨水较多,较易受天气状况干扰,因此,相对于封闭的大棚种植环境,氯噻啉在露地环境下降解速率更高,与青菜上噻虫嗪、啶虫脒等其他新烟碱类农药在大棚与露地环境中的降解趋势相符^[19]。

3.2 良好农业实践（GAP）选择

农药使用中的GAP包括农药的使用剂量、施药方法、施用次数及安全间隔期（pre-harvest interval,PHI）,PHI指作物采收距最后一次施药所需要的间隔时间,是作物最后一次施药后到残留量降至最大残留限量值（maximum residue limit,MRL）以内所需要的最短间隔时间^[28,29]。GB2763-2019尚未制定青菜上氯噻啉的MRL,较为相关的是氯噻啉在结球甘蓝上的临时MRL值为0.5 mg·kg^-1[25]。以10%氯噻啉可湿性粉剂的最大推荐剂量或1.5倍推荐剂量为施药剂量在青菜上喷雾2—3次,冬季大棚、夏季露地及大棚内青菜上氯噻啉最终残留量均低于0.5 mg·kg^-1。前期药效试验显示10%氯噻啉可湿性粉剂对青菜烟粉虱药后7 d防效为82.9%—85.7%,间隔7 d施药满足残效期需求。青菜生长周期较短,夏季播种后35 d可采收,冬季稍长,烟粉虱具有较强的趋嫩性特征,幼苗2—3片真叶时即可能发生虫害^[30,31]。

3.3 风险评估不确定性分析

风险评估具有一定不确定性,在本研究中主要体现在4个方面：一是未进行急性膳食摄入评估,由于FAO/WHO农药残留联席会议（Joint Meeting of Pesticide Residues,JMPR）数据库尚未收录氯噻啉相关信息^[32],目前未查询到氯噻啉的急性参考剂量（acute reference dose,ARfD）以及是否需要制定ARfD,尚无法进行急性膳食摄入风险评估;二是氯噻啉残留量数据采用最大残留量,远高于平均残留量,且未考虑清洗、烹调等加工因子,计算所得风险商偏高;三是未考虑氯噻啉代谢物的安全性,由于氯噻啉代谢产物较多,标准品不易购得,且代谢产物的毒性、结构等研究仍不够深入,可能存在一定未知风险;四是本研究仅以青菜为单一的氯噻啉暴露途径,而居民日常还会通过摄入其他蔬果、谷物等多种途径接触氯噻啉,对居民整体的氯噻啉暴露风险评估仍存在一定局限性。后续可深入研究加工因子、平均残留量、代谢物、全膳食摄入途径等不确定性因素,制定更为精准的安全使用准则。

4 结论

不同种植环境下,10%氯噻啉可湿性粉剂在青菜上的残留量均随时间延长逐渐降低,且降解趋势符合一级动力学方程。整体上,在其他种植条件相同的情况下,夏季青菜中氯噻啉消解速率高于冬季,露地青菜中氯噻啉消解速率高于大棚,消解时间、种植条件及施药浓度均对氯噻啉在青菜上的消解残留有显著影响,与施药次数（施药间隔7 d）无显著相关性。

中国普通居民由青菜摄入氯噻啉的风险较低,未成年人群风险相对高于成年人群,慢性摄入风险均可接受。根据最终残留试验结果及参考MRL值,使用10%氯噻啉可湿性粉剂防治青菜上的烟粉虱,用药剂量为45—60 g（a.i）·hm^-2,间隔7 d施药,最多可施用3次,冬季安全间隔期7 d,夏季安全间隔期3 d。

参考文献 View Option 原文顺序
文献年度倒序
文中引用次数倒序
被引期刊影响因子

[1] 李敏, 赵会君, 屈欢, 雷茜. 新烟碱类杀虫剂潜在环境风险及光降解行为研究进展
农药, 2019,58(3):170-173.
[本文引用: 1]

LI M, ZHAO H J, QU H, LEI Q. Research progress on potential environmental risks and photodegradation of neonicotinoids insecticides
Agrochemicals, 2019,58(3):170-173. (in Chinese)
[本文引用: 1]

[2] DAI Y J, JI W W, CHEN T, ZHANG W J, LIU Z H, GE F, YUAN S D. Metabolism of the neonicotinoid insecticides acetamiprid and thiacloprid by the yeast rhodotorulamucilaginosa strain IM-2
Journal of Agricultural and Food Chemistry, 2010,58(4):2419-2425.
DOI:10.1021/jf903787sURLPMID:20112912 [本文引用: 1]
A yeast identified as Rhodotorula mucilaginosa strain IM-2 was able to degrade acetamiprid (AAP) and thiacloprid (THI) in sucrose mineral salt medium with half-lives of 3.7 and 14.8 days, respectively, while it did not degrade imidacloprid and imidaclothiz. Identification of metabolites indicated that R. mucilaginosa IM-2 selectively converted AAP and THI by hydrolysis of AAP to form an intermediate metabolite IM 1-3 and hydrolysis of THI to form an amide derivative, respectively. Metabolite IM 1-3 had no insecticidal activity, while the THI amide showed considerable insecticidal activity but was 15.6 and 38.6 times lower than the parent THI following oral ingestion and a contact test against the horsebean aphid Aphis craccivora , respectively. The inoculated R. mucilaginosa IM-2 displayed biodegradability of AAP and THI in clay soils.

[3] 陈燕玲. 中国自主创制的农药品种及登记情况
现代农药, 2017,16(3):1-9.
[本文引用: 1]

CHEN Y L. China's innovative pesticides and their registration
Modern Agrochemicals, 2017,16(3):1-9. (in Chinese)
[本文引用: 1]

[4] 中国农药信息网. 行业数据. (2019.11.25) [2019.11.25] http://www. chinapesticide.org.cn/hysj/index.jhtml.
URL [本文引用: 2]

China Pesticides Information Network. Industry Data. (2019.11.25) [2019.11.25] http://www.chinapesticide.org.cn/hysj/index.jhtml. (in Chinese)
URL [本文引用: 2]

[5] LI J Y, ZHANG S F, WU C C, LI C, WANG HY, WANG W, LI Z, YE Q F. Stereoselective degradation and transformation products of a novel chiral insecticide, paichongding, in flooded paddy soil
Journal of Agricultural and Food Chemistry, 2016,64(40):7423-7430.
DOI:10.1021/acs.jafc.6b02787URLPMID:27660850 [本文引用: 1]
Paichongding is a chiral neonicotinoid insecticide currently marketed as racemate against sucking and biting insects. Under anaerobic condition, all paichongding stereoisomers underwent appreciable degradation in soil during 100 days of incubation, with estimated t1/2 values between 0.18 and 3.15 days. Diastereoselectivity in paichongding degradation was observed, with enantiomers (5S,7R)- and (5R,7S)-paichongding being more preferentially degraded in soils than enantiomers (5R,7R)- and (5S,7S)-paichongding. The half-lives of (5R,7R)- and (5S,7S)-paichongding were 3.05 and 3.15 days, respectively, as compared to 0.18 day for (5R,7S)- and (5S,7R)-paichongding. A total of nine intermediates were identified, of which depropylated paichongding was the predominant metabolite and appeared to be stable and recalcitrant to further degradation. Paichongding is degraded via denitration, depropylation, nitrosylation, demethylation, hydroxylation, and enol-keto tautomerism, producing chiral and biologically active products. These findings could have implications for environmental risk and food safety evaluations.

[6] 肖昱. 茶树叶片农药残留化谢平台优化及氯噻啉降解的初步研究
[D]. 合肥: 安徽农业科学院, 2015.
[本文引用: 1]

XIAO Y. Optimize of the platform for pesticide residues on tea leaves and preliminary research on degradation of imidaclothiz
[D]. Hefei: Anhui Academy of Agricultural Sciences, 2015. (in Chinese)
[本文引用: 1]

[7] SIMON-DELSO N, AMARAL-ROGERS V, BELZUNCES L P, BONMATIN J M, CHAGNON M, DOWNS C, FURLAN L, GIBBONS D W, GIORIO C, GIROLAMI V, GOULSON D, KREUTZWEISER D P, KRUPKE C H, LIESS M, LONG E, MCFIELD M, MINEAU P, MITCHELL E, MORRISSEY C, NOOME D, PISA L, SETTELE J, STARK J, TAPPARO A, VAN DYCK H, VAN PRAAGH J, VAN DER SLUIJS J, WHITEHORN P, WIEMERS M. Systemic insecticides (neonicotinoids and fipronil): Trends, uses, mode of action and metabolites
Environmental Science and Pollution Research, 2015,22(1):5-34.
DOI:10.1007/s11356-014-3470-yURLPMID:25233913 [本文引用: 1]
Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicotinoids and fipronil currently account for approximately one third of the world insecticide market; the annual world production of the archetype neonicotinoid, imidacloprid, was estimated to be ca. 20,000 tonnes active substance in 2010. There were several reasons for the initial success of neonicotinoids and fipronil: (1) there was no known pesticide resistance in target pests, mainly because of their recent development, (2) their physicochemical properties included many advantages over previous generations of insecticides (i.e., organophosphates, carbamates, pyrethroids, etc.), and (3) they shared an assumed reduced operator and consumer risk. Due to their systemic nature, they are taken up by the roots or leaves and translocated to all parts of the plant, which, in turn, makes them effectively toxic to herbivorous insects. The toxicity persists for a variable period of time-depending on the plant, its growth stage, and the amount of pesticide applied. A wide variety of applications are available, including the most common prophylactic non-Good Agricultural Practices (GAP) application by seed coating. As a result of their extensive use and physicochemical properties, these substances can be found in all environmental compartments including soil, water, and air. Neonicotinoids and fipronil operate by disrupting neural transmission in the central nervous system of invertebrates. Neonicotinoids mimic the action of neurotransmitters, while fipronil inhibits neuronal receptors. In doing so, they continuously stimulate neurons leading ultimately to death of target invertebrates. Like virtually all insecticides, they can also have lethal and sublethal impacts on non-target organisms, including insect predators and vertebrates. Furthermore, a range of synergistic effects with other stressors have been documented. Here, we review extensively their metabolic pathways, showing how they form both compound-specific and common metabolites which can themselves be toxic. These may result in prolonged toxicity. Considering their wide commercial expansion, mode of action, the systemic properties in plants, persistence and environmental fate, coupled with limited information about the toxicity profiles of these compounds and their metabolites, neonicotinoids and fipronil may entail significant risks to the environment. A global evaluation of the potential collateral effects of their use is therefore timely. The present paper and subsequent chapters in this review of the global literature explore these risks and show a growing body of evidence that persistent, low concentrations of these insecticides pose serious risks of undesirable environmental impacts.

[8] GIORIO C, SAFER A, SáNCHEZ-BAYO F, TAPPARO A, LENTOLA A, GIROLAMI V, LEXMOND W B, BONMATIN J M. An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 1: New molecules, metabolism, fate, and transport
Environmental Science and Pollution Research, 2017. doi: 10.1007/S11356-017-0394-3.
DOI:10.1007/s11356-020-10655-wURLPMID:32895796 [本文引用: 1]
South Asia is comprised of several countries, including Bangladesh, Pakistan, India, and Sri Lanka, all ranked highly at risk of climatic variability. The region's susceptibility to climate change can be attributed to both its spatial and inherent characteristics. Considering the countries' high dependence on agricultural products, to support their economies and growing populations, it is vital to measure the factors impacting crop productivity. This study quantifies the change in temperature and precipitation, coupled with their respective effects on the productivity of three major crops, wheat, rice and cotton, within two of Pakistan's largest provinces: Punjab and Sindh. Based on the collated data, multivariate regression analysis is conducted. Moreover, highly vulnerable areas to climate change have been identified under RCP scenarios 4.5 and 8.5, until the end of this century. Results reveal that there is a substantial increasing trend in temperature, whereas precipitation has high inter-annual variability. Regression outcomes, based on fixed/random effects models, indicate that temperature above threshold values of 24.3 degrees C, 33.0 degrees C and 32.0 degrees C for wheat, rice and cotton, respectively, negatively impacts productivity (statistically significant). Precipitation is statistically insignificant in explaining its role in crop productivity. Overall, the region is heading towards temperature and threshold exceedances at an alarming rate, which will impact the overall availability of suitable crop-growing areas.

[9] 戴宝江. 新颖杀虫剂—氯噻啉
世界农药, 2005(6):46-47.
[本文引用: 1]

DAI B J. A new insecticide-imidaclothiz
World Pesticides, 2005(6):46-47. (in Chinese)
[本文引用: 1]

[10] 孙占刚. 上海新型蔬菜营销模式的调研与发展对策
中国蔬菜, 2018(11):12-17.
[本文引用: 1]

SUN Z G. Investigation and development strategies of the novel marketing model for vegetables in Shanghai.
China Vegetables, 2018(11):12-17. (in Chinese)
[本文引用: 1]

[11] 上海蔬菜食用菌协会. 上海地产蔬菜2019年7月产销月报
(2019.7.31) [2019.9.4] https://www.shsjx.org/10622.
URL [本文引用: 1]

Vegetables and Edible Fungi Society of Shanghai and CBU-Autostats of local vegetables in shanghai in July 2019
(2019.7.31) [2019.9.4] https://www.shsjx.org/10622.(in Chinese)
URL [本文引用: 1]

[12] 王敏权. 夏季青菜栽培与病虫害防治技术
上海蔬菜, 2017(2):23-24.
[本文引用: 1]

WANG M Q. Techniques of cultivation and insect control forBrassica chinensis growing in summer
Shanghai Vegetables, 2017(2):23-24. (in Chinese)
[本文引用: 1]

[13] 杜颖. 叶菜类蔬菜主要病虫害防治技术
现代农业科技, 2017(6):140-142.
[本文引用: 1]

DU Y. Techniques of pest control for leaf vegetable
Modern Agricultural Science and Technology, 2017(6):140-142. (in Chinese)
[本文引用: 1]

[14] 李义强, 曹爱华, 任广伟, 孙惠青, 徐金丽, 郑晓, 徐光军, 周显升, 龚道新. 氯噻啉对烟蚜的防治效果和烟叶中农药残留规律研究
中国烟草学报, 2010,16(4):63-66.
URL [本文引用: 1]
Field trial were carried out in three years to study the control effect of imidaclothiz against Myzus persicae and its residue in tobacco leaf. Results indicated that 40% imidaclothiz WDG with 16000 times dilution showed good control effect 10 days after being sprayed. Degradation of imidaclothiz in tobacco leaf was fast with half-life of 1.5~2.3 days.

LI Y Q, CAO A H, REN G W, SUN H Q, XU J L, ZHENG X, XU G J, ZHOU X S, GONG D X. The control effect of imidaclothiz against Myzuspersicae and its residue in tobacco leaf
Acta Tabacaria Sinica, 2010,16(4):63-66. (in Chinese)
URL [本文引用: 1]
Field trial were carried out in three years to study the control effect of imidaclothiz against Myzus persicae and its residue in tobacco leaf. Results indicated that 40% imidaclothiz WDG with 16000 times dilution showed good control effect 10 days after being sprayed. Degradation of imidaclothiz in tobacco leaf was fast with half-life of 1.5~2.3 days.

[15] 贺敏, 贾春虹, 朱晓丹, 赵尔成, 陈莉, 余平中. 40%氯噻啉水分散粒剂在稻田环境中的残留动态
农药, 2010,49(1):50-52.
[本文引用: 1]

HE M, JIA C H, ZHU X D, ZHAO E C, CHEN L, YU P Z. Residue dynamics of imidaclothiz 40% WG in rice
Agrochemicals, 2010,49(1):50-52. (in Chinese)
[本文引用: 1]

[16] 徐燕, 徐茜, 余鸿燕. 10%氯噻啉可湿性粉剂防治萝卜蚜虫田间药效试验
广西农业科学, 2007(3):282-284.
[本文引用: 1]

XU Y, XU Q, YU H Y. Effect of 10% imidaclothiz WP on controlling radish aphid in field trial
Guangxi Agricultural Sciences, 2007(3):282-284. (in Chinese)
[本文引用: 1]

[17] 吴明. 新烟碱类杀虫剂氯噻啉环境行为研究
[D]. 上海: 上海交通大学, 2010.
[本文引用: 2]

WU M. Study on nicotinoid imidaclothiz’s behaviors in environments
[D]. Shanghai: Shanghai Jiaotong University, 2010. (in Chinese)
[本文引用: 2]

[18] WU M, CAI J G, YAO J Y, DAI B J, LU Y T. Study of imidaclothiz residues in cabbage and soil by HPLC with UV detection
Bulletin of Environmental Contamination & Toxicology, 2010,84(3):289-293.
DOI:10.1007/s00128-010-9941-zURLPMID:20111945 [本文引用: 1]
The HPLC method for determination of imidaclothiz residue in cabbage and soil was developed, and its degradation and final residue were studied. The mean accuracies of the analytical method were 92.0-93.0% in soil and 88-93% in cabbage. The precision in cabbage ranged from 2.2% to 5.6%, and in soil from 2.0% to 5.0%. The minimum detectable amount of imidacothiz was 1 x 10(-10)g. The minimum detectable concentration was 0.0075 mg kg(-1) in cabbage and 0.003 mg kg(-1) in soil. The results showed that imidaclothiz degradation in soil and cabbage coincided with C = 0.0427e(-0.0923t), C = 0.739e(-0.279t). The half-lives were about 3.1 days in soil and 2.2 days in cabbage.

[19] 黄兰淇, 马琳, 占绣萍, 陈建波, 赵莉. 露地和大棚条件下噻虫嗪和啶虫脒在青菜中的残留及消解动态
农药, 2018,57(1):42-45.
[本文引用: 2]

HUANG L Q, MA L, ZHAN X P, CHEN J B, ZHAO L. Residue and decline study of thiamethoxam and acetamiprid in pakchoi under open field and greenhouse conditions
Agrochemicals, 2018,57(1):42-45. (in Chinese)
[本文引用: 2]

[20] 刘腾飞, 杨代凤, 钱辉, 陆皓茜, 董明辉. 氯氰菊酯在露地和大棚小白菜上的残留动态研究
中国农学通报, 2015,31(11):200-204.
[本文引用: 1]

LIU T F, YANG D F, QIAN H, LU H Q, DONG M H. Residue dynamics of cypermethrin in pakchoi under open field and greenhouse conditions
Chinese Agricultural Science Bulletin, 2015,31(11):200-204. (in Chinese)
[本文引用: 1]

[21] 郑坤明, 陈劲星, 陈冬花, 林瑶, 张钰萍, 苏建峰, 胡德禹. 吡蚜酮在大棚和露地芥蓝上的残留消解动态
农药, 2019,58(8):598-600.
[本文引用: 1]

ZHENG K M, CHEN J X, CHEN D H, LIN Y, ZHANG Y P, SU J F, HU D Y. Residue and dissipation of pymetrozine in Chinese kale under open field and greenhouse conditions
Agrochemicals, 2019,58(8):598-600. (in Chinese)
[本文引用: 1]

[22] NY/T 788-2004: 农药残留试验准则 北京: 中国农业出版社, 2004.
[本文引用: 1]

NY/T 788- 2004: Guideline on pesticide residue trials. Beijing: China Standards Press, 2004. (in Chinese)
[本文引用: 1]

[23] 钱永忠, 李耘. 农产品质量安全风险评估-原理、方法和应用. 北京: 中国标准出版社, 2007.
[本文引用: 1]

QIAN Y Z, LI Y. Risk Assessment for Quality Andsafety of Agro- Foods: Principles, Methodologies and Applications. Foods: Principles, Methodologies and Applications. Beijing: Standards Press of China, 2007. (in Chinese)
[本文引用: 1]

[24] 国家体育总局. 2014年国民体质监测公报
(2015.11.25) [2019.9.4] http://www.sport.gov.cn/n315/n329/c216784/content.html.
URL [本文引用: 1]

General Administration of Sport of China. Bulletin of fitness and health monitoring of Chinese citizen in 2014
(2015.11.25) [2019.9.4] http://www.sport.gov.cn/n315/n329/c216784/content.html.(in Chinese)
URL [本文引用: 1]

[25] GB2763-2019: 食品安全国家标准食品中农药最大残留限量. 北京: 中国农业出版社, 2019.
[本文引用: 2]

GB2763-2019. National food safety standard- Maximum residue limits for pesticides in food. Beijing: China Standards Press, 2019. (in Chinese)
[本文引用: 2]

[26] EU SANTE/11945/2015. Guidance document on analytical quality control and method validation procedures for pesticides residues analysis in food and feed
Directorate- Genaral for Health and Food Safety, European Union, 2015.
[本文引用: 2]

[27] 马畅. 土壤和水环境中氯噻啉的降解行为和降解产物研究
[D]. 北京: 中国农业科学院, 2019.
[本文引用: 1]

MA C. The degradation behaviors and products of imidaclothiz in soil and water
[D]. Beijing: Chinese Academy of Agricultural Sciences, 2019. (in Chinese)
[本文引用: 1]

[28] 宋稳成, 龚勇. 农药安全间隔期及其管理研究
农产品质量与安全, 2013(5):5-8.
[本文引用: 1]

SONG W C, GONG Y. Research and management of pre-harvest interval of pesticides
Quality and Safety of Agro-Products, 2013(5):5-8. (in Chinese)
[本文引用: 1]

[29] 韩丽君, 潘灿平, 钱传范. 最高残留限量和安全间隔期的计算方法(欧盟)
世界农药, 2005(3):37-41, 36.
[本文引用: 1]

HAN L J, PAN C P, QIAN C F. Calculation method of maximum residue limit and pre-harvest interval (European Union)
World Pesticides, 2005(3):37-41, 36. (in Chinese)
[本文引用: 1]

[30] 孔令娟, 张峻, 陈珏, 周晓晨, 张瑞明, 李恒松. 上海地区耐热青菜的生产和优势品种推荐
长江蔬菜, 2017(23):15-17.
[本文引用: 1]

KONG L J, ZHANG J, CHEN Y, ZHOU X C, ZHANG R M, LI H S. Production and recommendation of dominant variety for heat resistant pakchoi in Shanghai
Changjiang Vegetables, 2017(23):15-17. (in Chinese)
[本文引用: 1]

[31] 冯正娣, 林付根, 蔡长庚. Q型烟粉虱在叶类蔬菜上的发生特点与防治技术
安徽农学通报, 2008,14(19):179-181.
[本文引用: 1]

FENG Z D, LIN F G, CAI C G. Occurrence characters and control technology of bemisia tabaci (Q) in leaf vegetables
Anhui Agricultural Science Bulletin, 2008,14(19):179-181. (in Chinese)
[本文引用: 1]

[32] Joint Meeting of Pesticide Residues. Inventory of evaluations performed by the Joint Meeting on Pesticide Residues (JMPR)
(2019.11.25) [2019.11.25] http://apps.who.int/pesticide-residues-jmpr-database/Home/ Range/G-I.
URL [本文引用: 1]