浙江居民毒死蜱和氯氰菊酯的长期膳食暴露与风险评估

基于2007 -2008年浙江省市场销售农产品中毒死蜱和氯氰菊酯残留的监测数据及浙江不同人群的各类食物摄入量和体重数据,采用分布点评估的方法,评估了浙江省20个不同年龄、性别组人群毒死蜱和氯氰菊酯的长期膳食暴露风险水平。结果表明,浙江省不同年龄、性别组人群毒死蜱长期膳食暴露带来的慢性风险仍控制在较低水平范围内,只有当长期食用毒死蜱残留超过监测资料中的99th百分位点值(蔬菜、水果和大米分别为0.395,0.165和0.011 mg/kg)的食物时,才可能产生不可接受的较大风险。而氯氰菊酯的膳食暴露风险更低,即使长期持续食用的果蔬产品中氯氰菊酯残留都达到监测资料中的最大残留值(蔬菜和水果分别为1.830和0.519 mg/kg),其膳食暴露风险仍属于可接受水平。对膳食暴露的贡献率分析结果显示,蔬菜类食品仍是浙江居民毒死蜱和氯氰菊酯膳食暴露的主要来源,控制蔬菜 中毒死蜱和氯氰菊酯残留是降低这2种农药膳食暴露风险的关键。     

清洗及烹饪对芥菜和普通白菜中残留虫螨腈和高效氯氰菊酯膳食暴露风险的影响

为明确不同清洗和烹饪方式对芥菜和普通白菜中残留2种脂溶性农药(虫螨腈和高效氯氰菊酯)膳食暴露风险的影响,模拟厨房常用5种清洗方式(食用盐水、食用小苏打水、淘米水、自来水、食用醋水溶液)分别清洗芥菜和普通白菜,以及4种烹饪方式(煮、蒸、炒、腌制)烹饪加工后,利用QuEChERS样品前处理及气相色谱-串联质谱(GC-MS/MS)、超高效液相色谱-串联质谱(UPLC-MS/MS)方法检测样品加工前后虫螨腈和高效氯氰菊酯的残留量变化,计算加工因子,并根据我国3个代表性人群(儿童、育龄妇女、一般人群)的膳食数据,估算加工前后农药膳食暴露量变化以及对长期膳食暴露风险的贡献率(ADIi%)和短期膳食暴露风险(%ARfD)的影响,评价了清洗和烹饪加工过程对减少农药残留膳食暴露风险以及降低膳食暴露风险评估不确定性的作用。结果表明：芥菜采用食用小苏打水清洗,普通白菜采用食用盐水清洗,对2种农药残留的去除效果最好,显著优于自来水清洗;经过清洗、烹饪后,其加工因子(PFTotal)在芥菜中介于0.06～0.24 (虫螨腈)和0.04～0.11 (高效氯氰菊酯)之间,在普通白菜中介于0.05～0.21 (虫螨腈...     

降解菌株DG-S-01对菜薹和土壤中3种拟除虫菊酯类农药降解动力学的影响

通过室内盆栽和大田小区试验,测定了降解菌株苍白杆菌Ochrobactrum sp.DG-S-01对高效氯氰菊酯、高效氯氟氰菊酯和氰戊菊酯在菜薹和土壤中的降解动力学的影响。结果表明,降解菌株DG-S-01可有效去除菜薹和土壤中3种供试农药的残留,且降解过程符合一级动力学模型,降解半衰期(t1/2)与未经该菌株处理的对照相比缩短1.5～53.2 h。在菜薹中,3种农药的残留量均随降解菌处理时间的延长而降低,处理72 h后,高效氯氰菊酯和高效氯氟氰菊酯的残留量均小于0.5 mg/kg的水平。在土壤中,高效氯氰菊酯和高效氯氟氰菊酯残留量也随降解菌处理时间的延长而降低,处理72 h后,其残留量小于1 mg/kg的水平;而氰戊菊酯在土壤中的残留量则呈现先上升后下降的趋势。对照菜薹和土壤中3种农药的残留量均明显高于喷施降解菌株的处理。     

五种加工方式对黄瓜中10种农药残留的去除效果

在实验室模拟沉积农药条件下,通过液相色谱-串联质谱 (LC-MS/MS) 和气相色谱-串联质谱 (GC-MS/MS) 检测技术,研究了经水洗、水煮、炒制、去皮和腌制5种加工方式后,多菌灵、吡虫啉、啶虫脒、乙霉威、霜霉威、丙溴磷、氯氰菊酯、三唑磷、敌敌畏和嘧霉胺10种农药在黄瓜中的残留量变化情况。结果表明:在5种加工方式中,以去皮处理对农药的去除效果最明显,其中丙溴磷和氯氰菊酯的加工因子 (PF) 均为0.04,其他4种加工方式对农药去除效果的强弱顺序为水煮>炒制、水洗、腌制;农药的log K_ow(辛醇水分配系数) 值跟农药的去除效果直接相关,经水洗和水煮2种加工方式处理后,农药的log K_ow值越小,越易被去除。另外,水洗、水煮和炒制处理,在0~10 min内随处理时间延长农药残留量呈减小的趋势,10种农药的PF变化范围为:水洗时PF在1.00~0.62之间,水煮时PF在0.86~0.37之间,炒制时PF在1.13~0.52之间。     

高效氯氰菊酯和吡丙醚在芥蓝中的残留消解及膳食暴露风险评估

为明确高效氯氰菊酯和吡丙醚在芥蓝上施用后的残留行为和膳食暴露风险, 研究基于规范田间残留试验、目标农药在芥蓝上残留分析方法, 得到芥蓝中2种农药的残留水平, 结合我国膳食结构不同性别/年龄组食物消费量及体重数据评估了高效氯氰菊酯和吡丙醚对各类消费人群的长期和短期膳食摄入风险。结果表明:高效氯氰菊酯和吡丙醚分别在0.01~1.0 mg/L和0.005~1.0 mg/L范围内线性关系良好, 决定系数(R2)≥0.996 7。在3个添加水平下, 芥蓝中2种农药的平均回收率为70.6%~113.4%, 相对标准偏差(RSD)为0.5%~8.5%, 定量限均为0.01 mg/kg。10%高氯·吡丙醚微乳剂以推荐高剂量施药, 高效氯氰菊酯和吡丙醚在芥蓝中的消解符合一级动力学, 半衰期分别为3.9~10.1 d和4.8~6.3 d。最终残留试验结果表明, 最后一次施药3、5、7、10 d后, 芥蓝中高效氯氰菊酯的最终残留量≤0.904 mg/kg, 吡丙醚的最终残留量≤0.202 mg/kg。膳食风险评估表明, 我国不同人群的长期慢性暴露风险最大值为27.26%;短期急性暴露风险最大值为67.17%, 表明对不同年龄段、不同性别人群健康不会产生不可接受的风险。     

加工过程对农药残留的影响研究进展

加工过程对农药残留的影响常用加工因子(Processing Factors,PF)来表示。加工不仅可以改善果蔬的食用特性,还对果蔬中农药残留具有重要影响。果蔬在食用前通常经历加工处理有清洗、去皮、烹饪等,某些农产品还会通过腌制、脱水等处理以改善保藏时间和食品风味。本文以常用的家庭处理为出发点,综述了加工过程对农药残留的影响,为确定合适的家庭处理方法提供参考,为膳食暴露评估提供数据依据,从而最大程度的减少食品中农药残留量,以维护消费者身体健康。     

人参中3种农药残留分布规律及短期膳食风险评估

为了解人参不同部位中农药残留分布规律及膳食风险，分别取黑龙江省鸡东市2、3、4年参，虎林市2、3、4、5、6年参，针对其芦头、主根及须根建立了气相色谱-质谱联用(GCMS)检测技术，分别测定了其中五氯硝基苯、六氯苯及毒死蜱的残留量，并就人参中3种农药残留的短期膳食风险进行了评估。72份人参样品中，五氯硝基苯检出率为74%，检出残留量在0.005～0.062 mg/kg之间；六氯苯检出率为78%，残留量在0.057～0.150 mg/kg之间；毒死蜱检出率为61%，残留量在0.018～0.073 mg/kg之间。2020版《中国药典》规定人参中五氯硝基苯和六氯苯的最大允许残留限量(MRL)均为0.1 mg/kg，所检测样品中，虎林市5、6年参芦头及6年参主根中六氯苯的残留量超过了该限量标准，超标率分别为2.8%、5.6%和2.8%。总体而言，农药残留水平随人参种植年份的增加而升高，人参各部位中累积的农药残留量由高到低分别为芦头>主根>须根，同时其短期膳食风险商(RQST)远小于100%，说明通过人参摄入的农药残留对人体不会产生不可接受的短期膳食暴露风险。     

中国食品中农药MRL标准对急性膳食暴露评估需求的研究

为了评估当前国内相关农药最大残留限量(MRL)标准及我国居民的急性膳食暴露风险水平,采用FAO/WHO农药残留专家联席会议(JMPR)推荐的农药残留急性膳食暴露评估方法,利用我国居民大份额膳食消费数据、国内登记农药的规范残留试验数据和JMPR推荐的农药毒理学数据,对我国普通人群、0~6岁儿童和育龄妇女的农药残留摄入情况进行了急性膳食暴露评估。结果表明:白菜中的虫螨腈和丙森锌、甘蓝中的高效氯氰菊酯和灭多威对三类人群的国家估算急性暴露水平(NESTI)均大于急性参考剂量(ARf D);香蕉中的氟硅唑对0~6岁儿童和普通人群的NESTI分别为ARf D值的300%和160%;苹果中的二氰蒽醌、甘蓝中的高效氯氟氰菊酯、花椰菜中的阿维菌素及番茄中的丙森锌仅对0~6岁儿童有较高的急性膳食暴露风险;儿童相比其他人群摄入农药残留的急性膳食暴露风险更高、概率更大。建议我国采取相应的风险管理措施,降低农药残留摄入的急性膳食风险,同时尽快完善短期膳食消费数据库和农药残留数据库,在制定农药MRL标准时进行相应的急性膳食暴露评估,以保障消费者的农药急性膳食暴露风险在可接受水平。     

稻谷加工过程中4种常用杀虫剂残留的消解规律

为控制水稻籽粒中农药的残留量,提高稻米食用的安全性,研究了稻谷中三唑磷、毒死蜱、丁硫克百威和氯虫苯甲酰胺4种杀虫剂从农田到餐桌的残留消解规律,阐明了水稻生长后期4种农药的施药期、用药量、采收间隔期与籽粒中农药残留分布的关系,并结合食用加工过程,分析了稻米入口前农药的残留消解情况,评估了稻米食用的安全性。田间试验参照农药登记残留试验准则进行,采用液相色谱-串联质谱法测定4种农药在稻谷不同加工过种中的残留量。结果表明:脱壳和碾米2种稻谷加工过程对4种农药的去除具有促进作用,其加工因子 (P_F) 均小于0.5;稻米食用加工过程中淘洗2次结合高压蒸煮可有效降低4种农药在稻米中的残留量,P_F<0.2,可进一步提高农药摄入的安全性。农药种类、施药剂量与采收间隔期和稻米的安全性密切相关。氯虫苯甲酰胺和丁硫克百威主要分布在稻壳和谷糠中,两者占总含量的85%以上,因此即使蜡熟期施药1次,采收间隔期21 d,2种农药也均未检出;而毒死蜱和三唑磷在收获后的籽粒中仍有检出,残留量范围分别为0.032~0.043 mg/kg和0.053~0.073 mg/kg。精米中三唑磷含量分配比随采收间隔期延长先降低后增加,其累积具有显著的滞后性,使得三唑磷残留量高于中国国家标准中规定的最大残留限量 (MRL) 0.05 mg/kg,应适当延长采收间隔期以降低其最终残留量。即使在乳熟期施药,所有剂量处理收获后的大米经淘洗2次结合高压蒸煮后,4种农药的残留水平均低于MRL值。因此,适当的食用加工方式能够有效降低稻米中农药的残留量,提高稻米食用的安全性。     

杨梅中4种农药残留的膳食风险评估及家庭清洗去除效果

为明确杨梅中农药残留风险及去除效果,利用QuEChERS样品前处理方法结合高效液相色谱-串联质谱(HPLC-MS/MS)法测定了来自市场流通和生产环节的239个批次杨梅样品中检出率和残留量相对较高的4种农药(2,4-D、咪鲜胺、嘧菌酯和多菌灵)残留量.采用点评估方法评价了杨梅中4种农药的膳食暴露风险,并分别选择清水冲洗...     

四种农药在莼菜加工过程中的残留量变化

为了考察敌百虫、毒死蜱、氯氰菊酯和多菌灵4种农药在莼菜加工过程中的加工因子,从而优化莼菜的加工过程,分别模拟莼菜加工的清洗、杀青、护绿和储藏4个步骤,考察4种农药的加工因子,并分析每个步骤的相关因素对加工因子的影响。采用气相色谱-火焰光度检测器（GC-FPD）检测敌百虫和毒死蜱的含量,气相色谱-电子捕获检测器（GC-ECD）检测氯氰菊酯的含量,液相色谱-二极管阵列检测器（LC-DAD）检测多菌灵的含量。结果表明:随着清洗时间的增加,4种农药的加工因子逐渐变小,并在一定时间后趋于稳定;在供试的10 min内,杀青时间越长,4种农药的加工因子越小;护绿和储藏条件的改变对加工因子均无显著影响。综合考虑莼菜品质和农药残留两方面因素,建议莼菜清洗时间为30 min,在不影响莼菜品质的前提下尽量延长杀青时间。     

板兰根中三种拟除虫菊酯杀虫剂的残留分析

研究了板蓝根中3种拟除虫菊酯杀虫剂残留分析方法。以石油醚为萃取溶剂，分别用索氏抽 提法、浸渍振荡法、超声波法提取。提取液经100 mL丙酮∶0.05 mol/L氯化钙溶液(1∶1)液 -液分配净化后，以弗罗里硅土柱净化，5%乙酸乙酯-石油醚淋洗，气相色谱法电子捕获检 测器测定。结果表明，方法的线性范围为0.4×10-10～4×10-10g，氯氰菊酯 、氰戊菊酯、溴氰菊酯最低检测浓度分别为5×10-3、5×10-3、2×10-3 mg/kg。3种提取方法对板蓝根的添加回收率、变异系数符合农药残留分析的要求。     

Dynamics of pesticide residues in the autumn Chinese cabbage (Brassica chinensis L.) grown in open fields

Residues of the pesticides chlorpyrifos, dimethoate, cyhalothrin, cypermethrin, fenvalerate, deltamethrin and chlorothalonil in the autumn Chinese cabbage (Brassica chinensis L.) were studied using gas chromatography. The results indicated that the residues were dependent on the frequency and rate of pesticide application and on the weather conditions immediately following spraying. When the Chinese cabbages were treated once at normal rates, the half-lives of the seven pesticides in the vegetable were 4.7, 5.3, 2.9, 3.5, 5.4, 4.3 and 4.0 days respectively. Thus, based on the recommended preharvest intervals, the residual levels of all pesticides were within the national standards. When the Chinese cabbages were treated four times at maximal rates at 5 day intervals, the half-lives of chlorpyrifos, cypermethrin and chlorothalonil in the vegetable were 3.6, 2.9 and 5.9 days respectively, so that, based on the recommended preharvest intervals, the residual levels of chlorpyrifos and chlorothalonil exceeded the national standards for pollution-free vegetables, but the residual level of cypermethrin was within the national standard. Effects of rain on pesticide final residues in plants treated four times were more significant than in those treated once.     

高尔夫球场农药向大气中的挥发研究

高尔夫球场喷洒农药向大气中的挥发受农药性质、施药方式和环境条件的影响。用丙酮、二氯甲烷等有机溶剂作吸收液可较好地捕集空气中的氯氰菊酯、毒死蜱、百茵清等农药化合物。试验条件下,2,4-D丁酯、百菌清和氯氰菊酯在大气中的挥发损失率分别为6．31％、1.38％、7．20％,毒死蜱和灭多威的挥发损失率为0．78％和1．66％。相比之下,氯氰菊酯较易挥发,对空气的污染较大。选择性用药,采用颗粒剂撒施,可有效地减少农药挥发,有利于环境保护。     

Disposition kinetics of cypermethrin and fenvalerate in black bengal lactating goats

Disposition kinetics of cypermethrin and fenvalerate were investigated in lactating black Bengal goats following single dose intravenous administration at 57 and 45 mg kg^?1 respectively. The maximum and minimum blood concentrations of cypermethrin were 18.49 (±3.17) and 0.06 (±0.002) μg ml^?1, while the corresponding values for fenvalerate were 14.58 (±2.37) and 0.04 (±0.005) μg ml^?1 respectively. Both cypermethrin and fenvalerate remained present in blood for 36 h. The mean t1/2β) and Vd_area values were 5.56 (±0.28) h and 10.38 (±2.20) litre kg^?1 for cypermethrin and 5.66 (±0.35) h and 11.31 (±2.20) litre kg^?1 respectively for fenvalerate. Both cypermethrin and fenvalerate persisted in goat milk for 36 h. The t1/2β) and AUC values of fenvalerate were 7.37 (±1.84) h and 122.38 (±11.65) μg h ml^?1 whilst the corresponding values for cypermethrin were 6.66 (±1.54) h and 99.48 (±7.81) μg h ml^?1 in milk respectively.     

Effect of pesticides on spiders occurring on apple and citrus in Israel

Field experiments in an apple orchard and in a citrus grove were carried out to evaluate the effect of four commercial pesticides in common use in Israel against apple and citrus pests, on the spider populations inhabiting the trees. The spider populations on apple were markedly suppressed by the pesticides, the order of toxicity being Talstar (biphenate) >Mavrik (fluvalinate) > Smash (fenpropathrin) > Dursban (chlorpyrifos). When grapefruit trees were treated with carbaryl + formothion, 232 spiders were sampled in the unsprayed plot, 55 days after treatment, as compared with only 11 spiders in the treated plot. Two and 7 days after treatment with chlorobenzilate, the sample from the treated plot numbered 68 and 55 spiders, respectively, as compared with 50 spiders collected 24 h before treatment. In addition, laboratory tests were carried out to determine the susceptibility of the spiderChiracanthium mildei L. Koch to 17 pesticides. When the spiders were exposed to grapefruit leaves which had been dipped 1 h previously for 5 sec in the aqueous emulsions of the pesticides, chlorpyrifos, fenpropathrin, fenvalerate, phosphamidon and biphenate caused 100%, and cypermethrin and fluvalinate 60% mortality, whereas all the other pesticides tested - acaricides, fungicides and herbicides - caused about 10-40% mortality.     

Residues of synthetic pyrethroid insecticides on horticultural crops

Foliar applications of synthetic pyrethroids were made to several crops to determine residue levels at various intervals after application. On onions, residues of cypermethrin, permethrin and fenvalerate were negligible > 0.1 mg kg^?1, 7 days after application. On lettuce, residues of fenvalerate and permethrin were 0.8 mg kg^?1. On celery, residues of fenvalerate did not decline and ranged from 0.12 to 0.25 mg kg^?1 during the 14-day period. On green bush-beans, residues of permethrin and cypermethrin did not decline during the 14-day period and ranged from 0.1 to 0.6 mg kg^?1. By day 7, residues of cyfluthrin, cypermethrin, deltamethrin, fenvalerate and permethrin on strawberries were less than the acceptable maximum tolerance of 0.1 mg kg^?1 with the exception of cypermethrin, applied at the rate of 0.14 kg a.i. ha^?1 which gave a residue of 0.14 mg kg^?1.     

Impact of two synthetic pyrethroids and methomyl on management of the cabbage aphid,brevicoryne brassicae (L.) and its associated parasitoid,diaeretiella rapae (M'Intosh)

The effectiveness of two synthetic pyrethroids, cypermethrin and fenvalerate, and of methomyl applied to cabbage plants was tested against the cabbage aphid, Brevicoryne brassicae (L.), and its parasitoid, Diaeretiella rapae (M'Intosh). Dosage rates chosen were equivalent to the manufacturer's maximum and minimum recommendations. Methomyl was considerably more toxic to B. brassicae adults than the two synthetic pyrethroids used. Fenvalerate, at the lowest rate used (71 g ha^?1), showed satisfactory effectiveness in reducing aphid adult population on treated plants by c. 77% below that of the control. All insecticides and rates used significantly reduced the emergence of parasitoid adult D. rapae from mummified aphids compared to the control. Fenvalerate clearly had less impact on emergence than cypermethrin or methomyl at any dosage used, while methomyl has appeared to be the most toxic compound in this respect. Longevity of parasitoid adults was highly affected by insecticide application, particularly those adults emerging from mummified aphids exposed to methomyl or cypermethrin. However, only a slight difference in longevity was seen at the lower rate of 71 g ha^?1 of fenvalerate. At the lowest dosage rates used, methomyl and cypermethrin reduced the F₁-progeny of adult parasitoid females by 70.5% and 58.3%, respectively, of the control, whereas fenvalerate reduced the progeny by only 36.4%.