Residue behaviors and dietary risk of cyazofamid in turnip,onion and romaine lettuce assessed by a QuEChERS-LC-MS/MS methods

In this study, the dissipation, terminal residues and dietary risk of the cyazofamid residue in three globally consumed minor crops, turnip(Brassica rapa L.), onion(Allium cepa L.)and romaine lettuce(Lactuca sativa L.)were assessed by supervised field trials at 6 locations of China in 2020. A reliable QuEChERS-LC-MS/MS method was developed for simultaneous analysis of cyazofamid and its primary metabolite, 4-chloro-5-p-tolylimidazole-2-carbonitrile(CCIM). The average recoveries of cyazofamid and CCIM in turnip, onion and romaine lettuce were 79%–97% and 77%–99%, respectively. The half-lives of cyazofamid in these crops were 5.7–6.5, 5.3–8.7 and 5.8–6.5 days in turnip, onion and romaine lettuce, respectively, with the final cyazofamid residues at harvest all lower than limit of quantitation(LOQ, 0.01 mg/kg). The turnip roots, onion bulbs and romaine lettuce leaves grown in China under Good Agricultural Practices conditions and harvested 10, 14 and 5 days, respectively, after the cyazofamid SC(100 g/L)application, would be reasonably safe for consumption by the general population. The maximum residue limit(MRL)values of cyazofamid could be tentatively set as 10 mg/kg for turnip leaves, 0.3 mg/kg for turnip roots, 0.05 mg/kg for onion bulbs, and 10 mg/kg for romaine lettuce leaves.

Detection and Analysis of Pesticide Residues in Chinese Chives and Risk Assessment of Dietary Intake

[Objectives]This study was conducted to understand the status of pesticide residues and dietary intake risk of Chinese chives in Tangshan area. [Methods] Sixty eight kinds of pesticide residues in 415 Chinese chive samples collected from Tangshan area were qualitatively and quantitatively determined by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) and gas chromatography(GC) in 2020. [Results] The results showed that 41 kinds of pesticide residues were detected in the 415 Chinese chive samples, and the detection rate was 69.4%(288/415), and there was a combination of pesticides in many samples. According to the National Food Safety Standard―Maximum Residue Limits of Pesticides in Food(GB 2763-2019), the residues of 12 pesticides exceeded the maximum residue limits(MRLs), and the unqualified rate was 38.07%(158/415). The highest detection rate of clothianidin was 41.20%(171/415), but there was no MRL in GB 2763-2019. The next was procymidone, the detection rate of which was 35.42%(147/415), and the over-standard rate was 30.12%(125/415). Forbidden and restricted pesticides were detected in some samples. According to the dietary exposure risk assessment, the NEDI/ADI values were all less than 1 and the intake risk was within acceptable range. In Tangshan area, the types of pesticides used in Chinese chive production are complex, and there are risks of multi-residue pollution and use of banned and restricted pesticides and unregistered pesticides. It is suggested that routine monitoring of pesticide residues and management of pesticide use should be strengthened to ensure the quality and safety of agricultural products. [Conclusions] This study provides a theoretical basis for the safe production of Chinese chive and the standardized and rational use of pesticides.

Risk factors for residual tumor after resection of hepatocellular carcinoma

AIM:To identify the clinicopathological risk factors correlated with residual tumor in hepatocellular carcinoma (HCC) patients after resection. METHODS:From January 2001 to April 2007,766 HCC patients who had undergone resection were included in this research. Lipiodol angiography was performed within 2 mo after surgery and followed by post-Lipiodol computed tomography (CT) 4 wk later for all 766 patients to monitor tumor in the remnant liver. Tumor detected within the first 3-mo postoperative period was defined as residual tumor. Patients were divided into 2 groups:disease or disease-free within the first 3 mo after surgery. Risk factors for residual tumor were investigated among various clinicopathological variables. RESULTS:A total of 63 (8.22%) patients were found to have residual tumor after surgery. Three independent factors associated with residual tumor were identified by multivariate analysis:preoperative serum α-fetoprotein (AFP) level [odds ratio (OR) = 1.68 (95% confidence interval (CI):1.20-2.36)],tumor size [OR = 1.73 (95% CI:1.29-2.31)] and microvascular invasion [OR = 1.91 (95% CI:1.12-3.24)]. CONCLUSION:Residual tumor is related to AFP level,tumor size and microvascular invasion. Patients at high risk should undergo closer follow-up and could be candidates for multimodality therapy.

Residual Risk of Transmission of HIV and Hepatitis B and C by Blood Transfusion in Bukavu in the Democratic Republic of Congo

The aim of this study was to determine the incidence rates of HIV1/2 antibodies, HBV and HCV antibodies among voluntary blood donors and to estimate the residual risk of HIV, HBV and HCV infection among blood donors in Bukavu. We conducted a follow-up cohort study of volunteer blood donors who have made at least two blood donations in Bukavu (DRC) between January 2010 and December 2012. We recorded 2986 volunteer blood donors during the study period. The residual risk of viral transmission associated with the serological window was considered as equals to the incidence rate multiplied by the duration of the serological window period divided by 365. Seroprevalence in volunteer blood donors in Bukavu was 1.1% for HIV 1/2 antibodies, 4.0% for HBs Ag and 2.1% for hepatitis C antibody. The number of conversion between two blood donations (incident cases) were observed is 8, 12 and 37 donors respectively for HIV 1/2, HCV and hepatitis B between 2010 and 2012. Incidence rates reported for 1000 person-years were 11.0 for HIV, 51.7 for HBV and 17.1 for HCV. The residual risk as estimated from the window was 0.6 per 1000 donations or 1/1.515 donations for HIV, 3.1 per 1000 donations or 1/329 for HCV and 7.9 per 1000 donations or 1/126 donations for hepatitis B. The residual risk is high. The screening tests are not enough to ensure safe blood. The reduction of residual risk would be achieved through the effectiveness of preventive measures taken for transfusion chain, before and after the biological qualification of blood donation.

Multiple Pesticide Residues in Bananas Sold in Tangshan City and Dietary Risk Assessment

[Objectives]This study was conducted to investigate the pesticide residue status of bananas in Tangshan area and the dietary intake risk of consumers.[Methods]High-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was applied to detect 70 pesticide residues in 191 batches of banana samples extracted from Tangshan area,and chronic and acute risk assessments were conducted.[Results]Among the 191 batches of bananas,172 batches of samples were detected to contain agrochemicals,with a detection rate of 90.05%.Seventeen agrochemicals were detected,accounting for 24.29%of the total agrochemicals tested.There was a phenomenon of multiple pesticide residues in a single sample,and high detection rates were found in carbendazim(49.21%),prochloraz(41.88%),pyraclostrobin(34.03%)and imidacloprid(30.37%).According to GB 2763-2021 National Food Safety Standards—Maximum Residue Limits for Pesticides in Food,the over-standard rate of imidacloprid was 17.8%;and the chronic and acute dietary risks of the 17 pesticide residues were all less than 100%.[Conclusions]The pesticide residues in bananas consumed by consumers on a daily basis do not pose unacceptable dietary risks.

Residual Cardiovascular Risk—Is Inflammation the Primary Cause?

Every cardiovascular clinical trial that has examined the beneficial effects of lowering LDL cholesterol to prevent cardiovascular events has demonstrated residual cardiovascular risk in the interventional treatment group. Residual risk is the term applied to the cardiovascular events (e.g., myocardial infarction, stroke, and cardiovascular death) that occur in spite of being on “optimal” medical therapy. This term is usually applied to secondary intervention studies,?i.e., lipid lowering treatments in subjects who have already had at least one cardiovascular event. Studies that described residual risk have attributed it, at least in part, to the fact that the LDLc has not been lowered sufficiently to stop atherosclerotic plaque formation and rupture into the arterial lumen. However, a recent cardiovascular intervention clinical trial which achieved a very low group median LDLc of 30 mg/dl still demonstrated significant residual risk. Of more importance to reducing residual risk may be addressing the ongoing inflammation in the coronary arteries that results in cellular liberation of cytokines and proteases that attack the atherosclerotic plaque’s fibrous cap. Recent studies have shown that inflammation may act independently of LDL to cause cardiovascular events. This article provides evidence that inflammation is the primary cause of residual risk and will need to be treated as aggressively as LDL lowering if CVD events in the post treatment period are to be significantly reduced. Addressing major risk factors including obesity, diabetes, smoking, hypertension and hyperlipidemia are critical to reducing inflammation. Statins and aspirin are the mainstay medications to reduce ongoing inflammation. However, newer pharmaceuticals may also be required to reduce inflammation to undetectable levels. Targeting inflammation to eradicate residual cardiovascular risk will be the next therapeutic challenge facing primary care physicians.

The Options Are Available for Controlling Residual Risk

Macquarie Dictionary define‘Risk’as the chance of an adverse event depending on the circumstances.In the field of engineering,the risk is often described as a specific unwanted event and including the consequences or loss.Usually residual risk from civil engineering project would lead to serious effects.The control of residual risk is an important subject in modern civil engineering management research.In this paper,a residual risk controlling methods will be present.Firstly,the definition and other mentioned concepts will be introduced.It includes the definition of residual risk and other concepts of risk that are often confused.Next,basic ways of dealing risk will be mentioned.

Environmental availability and ecological risk assessment of heavy metals in zinc leaching residue

Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order：CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue.

Risk assessment and ranking of pesticide residues in Chinese pears

The presence of pesticide residues in pears is a serious health concern. This study presents the results from a 2-year investigation （2013-2014） that used gas chromatography, GS/MS and UPLC/MS-MS to measure the levels of 104 pesti- cides in 310 pear samples. In 93.2% of the samples, 43 pesticides were detected, of which the maximum residue levels （MRLs） were exceeded in 2.6% of the samples. Multiple residues （two to eight compounds） were present in 69.7% of the samples; one sample contained nine pesticides and one sample contained 10. Only 6.8% of the samples did not contain residues. To assess the health risks, the pesticide residue data have been combined with daily pear consumption data for children and adult populations. A deterministic model was used to assess the chronic and acute exposures based on the Joint Meeting on Pesticide Residues （JMPR） method. A potential acute risk was demonstrated for children in the case of bifenthrin, which was found to be present at 105.36% of the acute reference dose （ARfD） value. The long- term exposure of the Chinese consumer to pesticide residues through the consumption of raw pears was far below the acceptable daily intake （ADI） criterion. Additionally, the matrix ranking scheme was used to classify risk subgroups of pesticides and pear samples. In general, 95.5% of samples were deemed to be safe and nine pesticides were classified as being of a relatively high risk. The findings indicated that the occurrence of pesticide residues in pears should not be considered a serious public health problem. Nevertheless, a more detailed study is required for vulnerable consumer groups, especially children. Continuous monitoring of pesticides in pears and tighter regulation of pesticide residue standards are recommended.

Pesticide residues in bayberry(Myrica rubra)and probabilistic risk assessment for consumers in Zhejiang,China

As pesticide residues in bayberry has raised serious concern from the public in China, a monitoring survey was carried out during 2013–2014 and 157 samples were analyzed in total. Twenty-three pesticides were detected among the 44 pesticides analyzed and at least one pesticide was detected in 63% of 99 samples. Whereas 45.6% of samples were found with two or more pesticide residues, and 23.6% of samples with four or more pesticide residues. Probabilistic risk assessments indicated that estimated daily intake（EDI） of cyhalothrin at the P97.5th percentile level is 1.11 times larger than the acceptable daily intake（ADI） for children, the estimated short-term intake（ESTI） at the P97.5th percentile level is 1.9 and 1.78 times larger than the acute reference dose（ARf D） for adult and children, respectively, indicating the potential risk concern from pyrethroids. EDI of the pesticides with anti-androgenic effects ranged from 0.15–2.46 of ADI, the probability of exposure exceeding the ADI was 7.1 and 31.1% for adults and children, respectively, the probability of exposure of pyrethroids exceeding the ADI was 3.8% for children. Exposures for other pesticides and groups were below 1.0. Because the co-occurrence of frequency of cyhalothrin and cypermethrin was 9.55%, the combinations of pesticides detected with anti-androgenic effects has not been found in the present monitoring, the results indicate that the pesticide residues in bayberry will not constitute serious public health risk, however, they are significant for the management of pesticide use on bayberry and dietary health risk in China.

Multi-Residue Levels of Persistent Organochlorine Pesticides in Edible Vegetables: A Human Health Risk Assessment

Background: This study evaluates the quantitative assessment of persistent organochorine pesticide (OCPs) residues in vegetables (Senecio biafrae) from four selected cocoa plantations in Ekiti State, Nigeria. Methods: The pesticides were extracted from the vegetable samples by using USEPA 3500C method and later clean-up on activated silica gel. The pesticides residues in the samples were determined using Gas Chromatography coupled with Electron Capture Detector (GC-ECD). Results: The results showed that the analyzed samples were contaminated with ten OCPs. The mean OCPs concentration ranged from ND—0.399 mg/kg to ND—0.379 mg/kg during the wet and dry seasons respectively. α-BHC, β-BHC, p, p’-DDE, dieldrin, endrin, endosulfan sulphate and methoxychlor were not detected in the samples. Pesticides such as aldrin, endosulfan II, endrin aldehyde and heptachlor slightly exceeded their maximum residue limit. Conclusion: The hazard indices (HI) of heptachlor, endosulfan I, endosulfan II, aldrin, heptachlor-epoxide and p, p’-DDT exceeded 1 and thus pose likely potential non-carcinogenic health risk.

Health Risk Assessment on Pesticide Residues in Drinking Water in Shenzhen

Objectives: To conduct health risk assessment of drinking water pesticide residues and its annual trend analysis in Shenzhen City. Methods: The samples of product water, pipe water and secondary supply water from 2011 to 2013 were collected and analyzed. The evaluation models of health risk assessments for children and adults on the 12 non-carcinogenic materials (namely heptachlor, pentachlorophenol, hexachlorocyclohexane, hexachlorobenzene, DDT, malathion, glyphosate, dimethoate, bentazone, atrazine, chlorothalonil, furadan) were recommended by the U.S. Environmental Protection Agency (US EPA). Results: The results showed that the maximums of the measured indicators in the above were controlled in accordance with the National Health Standards (GB5749-2006) published by Ministry of Health in China. The adults and children’s health indices (HIs) of the 12 non-carcinogenic materials were greater than 1 (2.323 - 6.312). Dimethoate residue in factory and peripheral water was the largest risks of harm among the non-carcinogenic pollutants measured. And its HIi (Its Hli) was also greater than 1 (1.995 - 5.094) and followed by hexachlorobenzene and heptachlor. Annual rising trend on health risk of the 12 pesticide residues indicated that their HIT on adults was 2323. 18 × 10-3 in 2011, 2340. 18 × 10-3 in 2012 and 2431. 97 × 10-3 in 2013, and HIT on children was 2965. 07 × 10-3 in 2011, 2986. 77 × 10-3 in 2012 and 3103. 93 × 10-3 in 2013, respectively. This study also suggested that the average risk of peripheral water samples (HIT was equal to 2619. 64 × 10-3) was greater than the factory samples’ (HIT was the same as 2366. 92 × 10-3), and the children’s health risk was greater than the adults’. Conclusions: Health risks of drinking water pesticide residues in Shenzhen have exceeded the threshold values. The dimethoate was the main hazard and had been rising annually, and the children’s health risk was greater than the adults’.

MRD-directed and risk-adapted individualized stratified treatment of AML

Measurable residual disease(MRD)has been widely recognized as a biomarker for deeply evaluating complete remission(CR),predicting relapse,guiding pre-emptive interventions,and serving as an endpoint surrogate for drug testing.However,despite the emergence of new technologies,there remains a lack of comprehensive understanding regarding the proper techniques,sample materials,and optimal time points for MRD assessment.In this review,we summarized the MRD methods,sample sources,and evaluation frequency according to the risk category of the European Leukemia Net(ELN)2022.Additionally,we emphasize the importance of properly utilizing and combining these technologies.We have also refined the flowchart outlining each time point for preemptive interventions and intervention paths.The evaluation of MRD in acute myeloid leukemia(AML)is sophisticated,clinically applicable,and technology-dependent,and necessitates standardized approaches and further research.

环嗪酮在蓝莓上的残留及其膳食风险评估

为探明环嗪酮在蓝莓上的最终残留量,在我国浙江、吉林、辽宁和北京4地开展了75%环嗪酮水分散粒剂的田间残留实验。采用电喷雾电离正离子模式,建立超高效液相色谱-串联质谱法测定蓝莓中环嗪酮残留量的方法。样品经乙腈涡旋提取、盐包盐析,再用装有十八烷基键合硅胶(C_(18))和乙二胺-N-丙基硅烷材料的净化管净化后测定。考察方法的线性、基质效应、定量限、正确度和精密度(相对标准偏差)。在0.0001~0.01 mg/L范围内,环嗪酮的标准曲线方程的线性关系良好,r>0.9998;基质效应为-7.7%;方法定量限为0.01 mg/kg。在0.01、0.1mg/kg和1.0mg/kg添加量范围内,环嗪酮在蓝莓中平均回收率为87%~91%,相对标准偏差不高于3.7%。4个实验点(浙江、北京、辽宁、吉林)最终残留实验结果显示:环嗪酮在实验点药后90d和100d的蓝莓样品中残留量均低于0.01mg/kg,低于美国、日本和韩国制定的最大残留限量值(分别为0.6、0.2mg/kg和0.05mg/kg)。膳食风险评估结果表明:普通人群环嗪酮的国家估算每日摄入量为0.0022mg,膳食摄入风险的风险熵为0.084%,膳食风险小。因此,建议75%的环嗪酮水分散粒剂在蓝莓园使用时,最高施药剂量为有效成分1800g/hm^(2),施药1次,安全间隔期为90d。

抑霉唑、咪鲜胺及其代谢物在荔枝贮藏保鲜中的残留动态及安全评价

为评估抑霉唑和咪鲜胺在荔枝全果、果皮和果肉的残留情况及膳食风险,本研究建立了同时测定抑霉唑、咪鲜胺及其代谢物含量的气相色谱-串联质谱法。该方法检测抑霉唑、咪鲜胺、咪唑乙醇和2,4,6-三氯苯酚的方法检出限(LOD)分别为2.0、3.0、6.0、0.3μg/kg;定量限(LOQ)分别为6.0、10.0、20.0、1.0μg/kg;在荔枝全果、果皮和果肉中的添加回收率为78.9%~107%、RSD为2.6%~5.8%。保鲜实验结果表明,抑霉唑、咪鲜胺浸果浓度越高残留量越高,残留物随贮藏时间延长由果皮逐渐迁移到果肉中。全果和果皮中抑霉唑、咪鲜胺的残留量随贮藏时间延长不断降低,果肉则于浸泡后第7 d达到最大值再逐渐消解。代谢咪唑乙醇和2,4,6-三氯苯酚随着贮藏时间增加不断升高。用质量浓度为500 mg/L的抑霉唑、咪鲜胺溶液分别浸泡保鲜,安全间隔期14 d内荔枝咪鲜胺的慢性、急性膳食摄入风险在可接受的范围内。

移植前控制营养状况和移植后微小残留病灶对多发性骨髓瘤患者自体造血干细胞移植预后的影响

目的:探讨多发性骨髓瘤患者自体造血干细胞移植前控制营养状况(CONUT)和移植后微小残留病灶对预后的影响。方法:回顾性分析2011-2020年在本院行自体造血干细胞移植的79例患者的临床资料,根据首次移植前CONUT评分将患者分为Low-CONUT组(0-4分,62例)和High-CONUT组(5-12分,17例),对比分析两组患者的临床特征、造血重建与不良反应、疗效和生存情况,同时对预后进行危险因素分析,并用时间依赖的ROC曲线验证结果。结果:High-CONUT组男性患者比例和初诊时骨髓浆细胞>30%的患者比例均较Low-CONUT组高(均P<0.05),而在造血重建与不良反应(2级以上的非血液学不良反应)方面无显著差异。Low-CONUT组移植前完全缓解率、完全缓解+非常好的部分缓解率都显著高于High-CONUT组(均P<0.05),移植后3个月后者优势仍然保持(P<0.01),但前者已无显著差异(P>0.05)。Low-CONUT组总生存期、无进展生存期均优于High-CONUT组(均P<0.05)。移植前的CONUT评分低(0-4分)、移植后6个月微小残留病阴性是患者总生存期和无进展生存期的有利因素(均P<0.05),初诊时国际骨髓瘤工作组预后危险分层为高危和移植前乳酸脱氢酶>250 U/L仅是无进展生存期的危险因素(均P<0.05)。时间相关的ROC曲线分析提示,CONUT评分和移植后6个月微小残留病灶状态可单独或联合预测1和2年总生存期、无进展生存期,且联合预测效果更好。结论:结合移植前CONUT评分和移植后微小残留病灶状态可以较好地预测多发性骨髓瘤患者的预后。

甘蔗中吡唑醚菌酯残留量检测及膳食风险评估

研究甘蔗中吡唑醚菌酯残留检测方法,并对最终残留量进行长期膳食摄入和短期膳食摄入风险评估。样品中吡唑醚菌酯采用QuEChERS前处理方法进行提取,高效液相色谱-三重四极杆串联质谱法检测;长期和短期膳食摄入评估采用膳食摄入风险评估模型进行。甘蔗中吡唑醚菌酯残留量为0.267~0.888 mg/kg。吡唑醚菌酯的普通人群国家估算每日摄入量是1.83 mg,占日允许摄入量的97%左右。甘蔗中吡唑醚菌酯在儿童和成人的国家估算短期摄入量占短期参考剂量(acute reference dose,ARfD)均<100%。按该试验的施药方式进行施药时,甘蔗中吡唑醚菌酯的残留量对一般人群健康风险在可接受的范围内。

改性磷石膏对污泥重金属迁移变化的影响机制

利用马铃薯渣和磷石膏的混合固废渣制备双改性材料(D-MPR),将其用于处理污泥重金属.研究双改性材料制备条件,材料对污泥Zeta电位、胞外聚合物(EPS)及重金属迁移的影响;重点分析处理后污泥中重金属的生态风险,并构建重金属迁移模型.实验结果表明:固废渣(PR)在碱化温度50℃,十六烷基三甲基溴化铵(CTAB)用量为2%PR(PR质量),醚化温度50℃的条件下,进行3h醚化改性;后再添加1%PR的过硫酸铵,80%PR的丙烯酰胺(AM),并在50℃下反应3h进行接枝改性,可制备得到D-MPR.将D-MPR以占污泥干固体(DS)量12‰的比例投入污泥中处理其中重金属,发现与原污泥相比,约42.43%的非稳态Cd,60.42%的非稳态Cr,53.10%的非稳态Cu,67.58%的非稳态Pb,55.21%的非稳态Zn,34.23%的非稳态Ni和74.68%的非稳态As被固定到污泥泥饼当中,污泥泥饼中重金属的迁移风险和潜在生态风险系数均明显降低.此外,该研究还发现了非稳态重金属转化率随LB-EPS以及TB-EPS含量的增加而减小,随Zeta电位的升高而升高,并以此建立了非稳态重金属的转化模型.

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。

枇杷中氟吡菌酰胺、肟菌酯及代谢产物残留分析与膳食风险评估

为明确氟吡菌酰胺和肟菌酯在枇杷上的残留与膳食风险,采用超高效液相色谱-串联质谱仪(ultra-performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测了枇杷中氟吡菌酰胺及其代谢物2-(三氟甲基)苯甲酰胺和肟菌酯及其代谢物肟菌酸在果实生长过程中的消解动态和残留量,并进行了膳食风险评估。样品采用乙腈提取,氨基固相萃取柱净化,UPLC-MS/MS检测。结果表明,在0.01~1.00 mg/kg添加水平下,回收率为82%~93%,相对标准偏差为1.4%~2.8%,定量限均为0.01 mg/kg,方法灵敏度及准确度良好,能够满足枇杷中农药残留检测要求。按照良好农业规范要求,在枇杷上施用43%氟吡菌酰胺·肟菌酯悬浮剂,当剂量为333 mg/kg、施药2次,施药间隔10~15 d,距末次施药后28、35 d时,枇杷中氟吡菌酰胺残留量为<0.01~0.03 mg/kg、消解率>90%;肟菌酯的残留量为<0.02~0.04 mg/kg、消解率>85%,肟菌酯的残留量低于我国规定的最大残留限量0.7 mg/kg。膳食风险评估表明,按照推荐剂量使用,枇杷中氟吡菌酰胺残留水平对一般人群健康不会产生不可接受的风险。研究结果可为氟吡菌酰胺和肟菌酯在枇杷树上的科学合理使用提供数据和技术支撑。