柴达木地区枸杞农药残留风险评估

对采自柴达木地区的枸杞进行农药残留检测,用%ADI和%ARfD进行农药残留慢性膳食摄入风险评估和急性膳食摄入风险评估,借鉴英国兽药残留委员会兽药残留风险排序矩阵进行农药和样品风险排序。结果显示,150个样品中有96个样品检测出了农药残留,检出了27种农药,其慢性膳食摄入风险和急性膳食摄入风险均很低。根据农药残留风险得分,检出的27种农药可分为3类,即高风险农药1种、中风险农药10种、低风险农药16种。据风险指数排序结果,150个枸杞样品均为低或极低风险。结果表明,柴达木地区枸杞农药残留检出率为64%,哒螨灵超标率最高达到了9.3%。柴达木地区枸杞农药残留慢性膳食摄入风险和急性膳食摄入风险均很低。柴达木枸杞应重点关注哒螨灵和毒死蜱农药残留。     

西安市鲜食葡萄农药残留风险评估

对西安市9个区县生产的200批次鲜食葡萄进行了58种农药残留风险检测摸底,分别用%ADI和%ARfD进行农药残留慢性膳食摄入风险评估和急性膳食摄入风险评估。结果显示,200批次样品中有196个样品有检出,共检出12种农药残留,均未超标。检出的12种农药残留的慢性膳食摄入风险%ADI值为0.068%～0.18%,平均值是0.053%;急性膳食摄入风险%ARfD值为0.18%～10%,平均值为3.41%。根据残留风险得分,12种农药残留风险评估得分共分为3类,分别是高风险农药(1种)、中风险农药(3种)、低风险农药(8种)。按风险指数排序,高风险样品所占比例为0,中风险、低风险、极低风险样品所占比例分别是4.5%、 41.5%、 54%。检出的12种农药残留中,吡虫啉、联苯菊酯、虫螨腈、阿维菌素4种农药尚未在葡萄中制定农药最大残留限量(MRL);烯酰吗啉、嘧霉胺、腐霉利、甲霜灵、啶虫脒的MRL值过严,异菌脲的MRL值过松,多菌灵、苯醚甲环唑的MRL和eMRL基本相同,制定合理;建议烯酰吗啉、嘧霉胺、吡虫啉、腐霉利、联苯菊酯、虫螨腈、啶虫脒、甲霜灵、异菌脲、阿维菌素在鲜食葡萄上的最大残留限量分别设为22、 22、 6.5、 11、1.5、 3.5、 7.5、 9、 6.5、 0.5 mg/kg。     

内蒙古马铃薯农药残留及膳食风险评估

对内蒙古主产区马铃薯样品进行农药残留监测,并对检出农药进行了急性和慢性膳食摄入风险评估。结果表明,在341份马铃薯样品的58种农药残留监测中,检出农药23种,农药残留阳性率为49.9%。检出的23种农药的慢性膳食摄入风险(%ADI)和有急性参考剂量的11种农药的急性膳食摄入风险(%ARfD)均远低于100%,其中克百威的慢性膳食摄入风险最高,矮壮素的急性膳食摄入风险最高。随着消费者年龄的增加,矮壮素、氯苯胺灵、克百威、多菌灵4种农药的急性和慢性膳食摄入风险呈逐渐下降的趋势;这4种农药在不同食用方式下,不去皮水煮/微波煮和不剥离炸芯片/薯条食用的急性膳食摄入风险明显高于其他食用方式。总体上,内蒙古马铃薯块茎产品中检出的农药残留以低毒农药为主,农药的急慢性膳食摄入风险均很低。     

猪肉中地塞米松兽药残留及摄入量风险评估

通过对华北某市猪肉中地塞米松兽药的残留监测,分析猪肉中地塞米松的残留水平,并评估其残留风险。试验采集500份猪肉样品,采用超高效液相色谱-串联质谱法对样品中地塞米松进行残留监测,并结合2015年我国居民膳食调查数据,使用专业风险评估软件@Risk,尝试构建非参数概率评估模型,对猪肉中地塞米松进行风险评估。结果显示,检测的猪肉中无超过国家限量标准(0.75g/kg)样品,含量范围为ND^0.38μg/kg(检出限为0.20μg/kg)。地塞米松兽药P99.5的暴露量EDI占ADI风险商HQ范围为0.0224~0.0635,远远<1,处于非常安全水平。结果表明,人群摄食动物性食品猪肉中的地塞米松兽药残留膳食性暴露风险较低,对人群不会产生不良作用。     

上海市地产芹菜中农药残留慢性膳食暴露风险评估

为了解上海市地产芹菜的农药残留情况及慢性膳食摄入风险水平,对2017-2022年采集的500份上海市地产芹菜样品中82种农药残留进行检测,并利用@Risk7.6软件,对芹菜的农药残留情况和慢性膳食暴露风险进行分析,以向各级监管部门提供后续芹菜质量安全监测的参考依据。结果表明,500份芹菜样品的农药残留总体检出率为31.4%,合格率为99.0%;共检出29种农药残留,烯酰吗啉、啶虫脒、腐霉利、吡虫啉、多菌灵和噻虫嗪的检出率较高;检出5份不合格样品,超标农药为噻虫嗪、灭蝇胺、氯氰菊酯、氯氟氰菊酯和苯醚甲环唑。在检出的样品中,82.8%的检出农药未在芹菜上登记,51.7%的农药暂未制定在芹菜中的最大残留限量标准,52.9%的样品同时检出2种及以上的农药残留。在慢性膳食暴露风险评估中,高检出率农药的平均风险值为0.002 18～0.041 6,均远小于1,表明居民通过食用上海市地产芹菜摄入农药残留的慢性风险处于可接受的水平,但有关部门仍需加强未登记农药的监测,从而进一步保障芹菜的质量安全。     

海南地区菜豆和豇豆中植物生长调节剂残留和风险评估

为了评估海南地区菜豆和豇豆中植物生长调节剂的残留水平和潜在健康风险,本研究在海南地区5个豆类蔬菜种植基地,采集菜豆和豇豆样品共100份,利用液相色谱三重四极杆串联质谱仪(LC-MS/MS)对矮壮素、多效唑、烯效唑、复硝酚钠、氯吡脲、噻苯隆、脱落酸共7种植物生长调节剂进行检测分析,并结合急性膳食摄入风险(%ARf D)和慢性膳食摄入风险(%ADI)评估方法,对这两种蔬菜中所有检出的植物生长调节剂进行风险评估。在菜豆样品中共检出矮壮素、多效唑、脱落酸、复硝酚钠等4种植物生长调节剂,检出率为16%~100%,且残留最大值为0.02~1.2 mg/kg,其中矮壮素和复硝酚钠的残留量超过欧盟最高残留限量标准,脱落酸的残留量明显高于植物激素自身含量;矮壮素、多效唑、复硝酚钠、脱落酸4种植物生长调节剂的%ARf D评估结果分别为0.081%、 0.020%、 0.033%、 1.568%,其%ADI评估结果分别为0.394%、 0.067%、 3.11%、 0.020%。在豇豆样品中共检出3种植物生长调节剂,分别为多效唑、脱落酸、复硝酚钠,检出率为8.0%~100%,残留最大值为0.036~1.179 mg/kg,且脱落酸的残留量明显高于植物激素自身含量。%ARf D评估结果分别为0.034%、 0.025%、 1.130%,%ADI评估结果分别为0.088%、 0.224%、 0.017%。实验结果表明,虽然海南地区菜豆和豇豆中部分PGR农药超过国家或欧盟最高残留限量标准,存在超剂量使用的情况,但是所有检出的PGR农药膳食暴露风险极低,均在可控范围内,尚不存在食品安全风险。     

重庆产地蔬菜农药残留调查及健康风险评价

2017年,对重庆近郊产地蔬菜(普通白菜、豇豆、菜豆、番茄、黄瓜)中的19种农药残留水平进行了分析,并采用兽药残留风险排序法与食品安全指数分析法对农药残留的健康风险进行评价。结果表明,烯酰吗啉、吡虫啉、氯虫苯甲酰胺、甲霜灵、腐霉利、哒螨灵的检出率居于前六位,且显著高于其他农药。根据GB2763-2016最大残留限值(MRL)判断,有9个菜豆样品治螟磷超限;有4个普通白菜超限,超限的农药分别为氟虫腈、毒死蜱、氧乐果、氯氰菊酯;豇豆、番茄各有1个样品超限,超限农药分别为氧乐果、苯醚甲环唑。根据兽药残留风险排序矩阵法评价,治螟磷、哒螨灵、阿维菌素、氟虫腈属高风险农药残留。根据农药残留安全指数分析法评价,氧乐果、氟虫腈对人体健康存在高风险,哒螨灵、治螟磷、烯酰吗啉对人体健康存在风险,但处于可接受范围内;其他农药对人体健康风险可忽略。综合两种评价方法得到的结果,为保证重庆产地蔬菜质量安全,应重视禁用农药治螟磷、氧乐果、氟虫腈的监管使用,还应重视哒螨灵、烯酰吗啉、阿维菌素、苯醚甲环唑、氯氰菊酯、氯虫苯甲酰胺、甲霜灵、腐霉利引起的食用风险。     

生鲜乳中四环素类药物残留的超高效液相色谱-串联质谱检测方法研究

建立生鲜乳中四环素类药物(四环素、土霉素、金霉素、多西环素)残留的超高效液相色谱-串联质谱(ultra-performance liquid chromatography tandem mass spectrometry, UPLC-MS/MS)的分析方法。样品用0.1 mol/L EDTA-Mcllvaine缓冲液进行提取,用HLB固相萃取柱进行净化,以0.1%甲酸和乙腈为流动相进行梯度洗脱,ZORBAX Eclipse Plus C18(2.1 mm×50 mm, 1.8μm)反相色谱柱进行分离,流速为0.4 m L/min,用UPLC-MS/MS进行分析,外标法定量。4种四环素类药物在1.0～500 ng/mL浓度范围内呈现良好的线性关系,相关系数R20.999,检出限为0.5μg/kg,定量限为1.0μg/kg,4种四环素类药物的平均加标回收率分别是四环素74.1%～106.8%,土霉素84.8%～99.0%,金霉素74.8%～105.5%,多西环素78.0%～104.0%, RSD≤3.3%(n=6)。该方法灵敏度高,重复性好,选择性强,适用于生鲜乳中四环素类药物残留的定量检测。     

甘肃枸杞中农药残留水平分析及风险评估

收集了93批甘肃不同产地的枸杞样品,对48种农药的残留量进行测定,用%ADI和%ARf D对检出农药进行慢性和急性膳食摄入风险评估,以危害指数法(HI)评估其累积暴露风险情况。结果显示, 93批枸杞中检出农药18种, 8种农药的检出率30%,其他农药的检出率为2.2%～18.3%; 18种检出农药的慢性和急性膳食摄入风险平均值为0.013%和0.026%,均远低于100%,其中啶虫脒的风险最高,其慢性和急性膳食摄入风险值为0.069%和0.19%;慢性和急性累积风险的危害指数分别为0.000 5和0.158 3,均远远小于1。结果表明,甘肃枸杞中的农药残留对人体健康不会造成危害,其安全性可被接受,但仍需加强监管,并考虑制定啶虫脒的最大残留限量值。     

QuEChERS-四极杆飞行时间高分辨质谱法快速筛查典型水产品中的喹诺酮类药物残留

以Qu ECh ERS样品预处理方法、四极杆飞行时间高分辨质谱(Q-TOF MS)为检测手段,建立了典型水产品中的15种喹诺酮类药物残留的快速筛查方法。样品采取5%甲酸乙腈提取,PSA和C_(18)净化,Q-TOF质谱正离子模式扫描定量,自建数据库定性。15种喹诺酮类残留药物检出限为0.5~1.5μg/kg,方法平均回收率在72.3%~102.1%,相对标准偏差在3.8%~13.2%。该方法快速、简便、准确,适用于典型水产品中喹诺酮类药物的快速筛查。     

Analysis of veterinary drugs and metabolites in milk using quadrupole time-of-flight liquid chromatography-mass spectrometry

A quadrupole time-of-flight (Q-TOF) liquid chromatography-mass spectrometry (LC-MS) method was developed to analyze veterinary drug residues in milk. Milk samples were extracted with acetonitrile. A molecular weight cutoff filter was the only cleanup step in the procedure. Initially, a set of target compounds (including representative sulfonamides, tetracyclines, β-lactams, and macrolides) was used for validation. Screening of residues was accomplished by collecting TOF (MS(1)) data and comparing the accurate mass and retention times of found compounds to a database containing information for veterinary drugs. The residues included in the study could be detected in samples fortified at the levels of concern with this procedure 97% of the time. Although the method was intended to be qualitative, an evaluation of the MS data indicated a linear response and acceptable recoveries for a majority of target compounds. In addition, MS/MS data were also generated for the [M + H](+) ions. Product ions for each compound were identified, and their mass accuracy was compared to theoretical values. Finally, incurred milk samples from cows dosed with veterinary drugs, including sulfamethazine, flunixin, cephapirin, or enrofloxacin, were analyzed with Q-TOF LC-MS. In addition to monitoring for the parent residues, several metabolites were detected in these samples by TOF. Proposed identification of these residues could be made by evaluating the MS and MS/MS data. For example, several plausible metabolites of enrofloxacin, some not previously observed in milk, are reported in this study.     

动物源食品中兽药残留高通量快速分析检测技术

随着养殖业的迅猛发展,动物源食品兽药残留问题日益成为食品安全领域的重要内容。动物源食品基质复杂,而其中残留的兽药含量甚微,传统的样品制备及检测方法大多存在检测样品基质种类单一、检测兽药种类范围小、耗时长、重现性差等问题,缺乏一定的通用性和准确性,已不能满足当前社会发展的需要。近年来,随着QuChERS法和高分辨质谱等先进样品制备和检测技术在兽药残留检测分析领域的应用,一批高通量、自动化乃至可视化的快速高效分析检测方法也随之而起,该文即对这些高通量快速样品制备和检测方法进行综述,同时对动物源食品中兽药残留的检测和监控等工作提出建议并进行了展望。     

Liquid chromatographic determination of multiple sulfonamide residues in bovine milk

A liquid chromatographic method has been developed for simultaneous determination of residues of 10 sulfonamide drugs at 10 ppb and above in raw bovine milk. The method is based on a chloroform-acetone extraction, evaporation of organic phase, dissolution of residues in an aqueous potassium phosphate solution, and extraction of fatty residue into hexane. The aqueous layer is collected, filtered, injected onto an LC system, and detected by ultraviolet absorption at 265 nm. To elute all 10 sulfonamides isocratically, 2 chromatographic conditions are required. Seven sulfonamides can be quantitated with 12% methanol in the mobile phase; 4 sulfonamides can be quantitated with 30% methanol. Sulfamethazine, the most widely used sulfonamide, is detected on both systems. Recoveries are 44-87% for individual sulfonamides, with only 2 below 60%. Coefficients of variation are 3-13% at 10 ppb.     

Residue methodology for AMDRO fire ant insecticide (AC 217,300) in pasture grass and crops

Residue methodology is described for the determination of AC 217,300 residues in pasture grass and crop samples. After extraction and subsequent cleanup on an XAD-2 column, residues of AC 217,300 are determined by liquid chromatography (LC), using a reverse phase paired-ion chromatographic system and detection at 300 nm. The method has a validated limit of sensitivity of 0.05 ppm with corresponding control values for the commodities analyzed of less than 0.01 ppm. Apparent residues over 0.05 ppm can be confirmed by either gas chromatography with an electron capture detector (GC-EC) or gas chromatography-negative ion chemical ionization mass spectrometry (GC-NICI). The direct GC-NICI method circumvents the need for sample cleanup on the XAD-2 column, and offers a greatly simplified procedure that is useful for screening samples. Recoveries of AC 217,300 from the commodities analyzed have been satisfactory with all methods of analysis.     

Antibiotic residues in animal-derived food

Antibiotics are used extensively in food-producing animals to maintain optimal health and promote growth. The use of these drugs has the potential to leave drug-related residues such as parent drug and metabolites in meat, milk, and eggs. For those drugs that require a withholding period to ensure that residues in the food products are below established tolerances, methods of analysis are required. The majority of approved antibiotics are assayed by microbiological methods. Although these methods are suitable for screening for drug residues, they often lack the specificity and precision required of regulatory methods. Present requirements for regulatory methods have resulted in the submission of physical-chemical methods in support of New Animal Drug Applications for antibiotics.     

Development of an immunochromatographic strip test for rapid detection of melamine in raw milk, milk products and animal feed

A simple, rapid and sensitive immunogold chromatographic strip test based on a monoclonal antibody was developed for the detection of melamine (MEL) residues in raw milk, milk products and animal feed. The limit of detection was estimated to be 0.05 μg/mL in raw milk, since the detection test line on the strip test completely disappeared at this concentration. The limit of detection was 2 μg/mL (or 2 μg/g) for milk drinks, yogurt, condensed milk, cheese, and animal feed and 1 μg/g for milk powder. Sample pretreatment was simple and rapid, and the results can be obtained within 3-10 min. A parallel analysis of MEL in 52 blind raw milk samples conducted by gas chromatography-mass spectrometry showed comparable results to those obtained from the strip test. The results demonstrate that the developed method is suitable for the onsite determination of MEL residues in a large number of samples.     

Simulation of soil organic carbon dynamics under different pasture managements using the RothC carbon model

Recently, soil carbon sequestration in agro-ecosystems has been attracting significant interest as soil organic carbon (SOC) can potentially offset some atmospheric carbon dioxide. The objectives of this study were to use the RothC model to simulate soil carbon sequestration and determine the proportion of pasture production as carbon input for SOC sequestration under different pasture types and pasture management in a long term experiment established in 1992. There were two types of pastures, annual and perennial pastures, with or without application of limestone. Simulation results showed that with an initial setting for the stubble retention factor of 0.65 and root/shoot ratio of 0.5 for annual pasture and 1.0 for perennial pasture, RothC can adequately simulate SOC for both pasture types, especially annual pasture. Using an inverse modelling technique, the root/shoot ratio was determined as 0.49 and 0.57 for annual pasture and 0.72 and 0.76 for perennial pasture with and without limestone application, respectively. There was a large improvement in model performance for perennial pasture with and without limestone application. The root mean squared errors (RMSE) reduced from 3.19 and 2.99 t C ha⁻¹ in the initial settings to 2.09 and 2.10 t C ha⁻¹, while performance efficiency (PE) increased from 0.89 and 0.91 to the same value of 0.95 when the root/shoot ratio of 0.72 and 0.76 were used for limed and unlimed perennial pastures. However, there was little improvement for annual pasture as RMSE had little change and PE was the same. As the stubble retention factor and root/shoot ratio can be combined into one factor that measures an equivalent amount of total above-ground pasture production allocated for soil carbon input, the modelled results can be summarised as 1.2 times and 1.4 times the above-ground dry matter for annual and for perennial pasture, respectively, regardless of liming. Our results provide useful information for simulation of soil carbon sequestration under continuous pasture systems.     

Analysis of beta-lactam antibiotics in incurred raw milk by rapid test methods and liquid chromatography coupled with electrospray ionization tandem mass spectrometry

A recently developed confirmatory LC-MS method has been applied to the quantification of five major beta-lactam antibiotics in suspect raw bovine milk samples that gave a positive response with receptor-based (BetaStar) and rapid microbial inhibitory screen tests (Delvotest SP). In total, 18 presumptive positive raw milk samples were reanalyzed; 16 samples showed traces of antibiotic residues that could be identified and quantified by the LC-MS method, ranging from the limits of confirmation up to 38 microg/kg. Of the positive samples, only five (approximately 30%) were found to be violative of EU maximum residue limits. The most frequently detected antibiotic residues were cloxacillin and penicillin G, the former often in combination with amoxicillin or ampicillin. This study compares the results obtained by the three methods on identical samples and addresses how these relate to certain criteria such as sensitivity and selectivity. Furthermore, the limitations of the LC-MS method and the potential impact of the presence of frequently more than one residue in the same milk sample on the response of the rapid test methods are discussed.     

Zinc,lead, molybdenum contamination in the vicinity of an electric steelworks and environmental response to pollution abatement by bag filter

A survey was made of environmental contamination and its consequences for cattle, by Zn, Pb, and Mo in the vicinity of an electric steelworks over a 5 yr period. The levels of the metals were determined in several samples such as airborne particles, atmospheric fallout and soils and pastures. Before a pollution control system was set up, the results showed a high contamination especially for atmospheric fallout and pastures. A slight excess of Mo in pastures associated with a high Zn content caused a Cu deficiency as shown by symptoms and biological measurements. After bag filters had been set up in the steelworks the levels of contaminant returned to normal in fallout and the pasture and all biological symptoms disappeared.     

Monitoring of domestic and imported eggs for veterinary drug residues by the Canadian Food Inspection Agency

The Canadian Food Inspection Agency (CFIA) routinely monitors the Canadian food supply to ensure that the levels of antibiotic residues are below the stated regulatory guidelines. Over a two-year period, both domestic and imported eggs in Canada were analyzed for a number of veterinary drugs. These included chloramphenicol, beta-lactams, fluoroquinolones, halofuginone, macrolides, sulfonamides, tetracyclines, decoquinate, and coccidiostats. More than 99% of the samples screened were found to be free of any veterinary drug residue. The remainder were found to contain tetracyclines, sulfonamides, ciprofloxacin, macrolides, streptomycin, clopidol, ethopabate, and nitromide. Current methods used for the analysis of these residues are discussed.