亚胺唑在梨上的残留行为及膳食风险评估

Residual Behavior and Dietary Risk Assessment of Imibenconazole in Pears

[目的]研究亚胺唑在梨上的残留行为,并进行膳食风险评估,建立了梨中亚胺唑的残留检测方法。[方法]样品经乙腈提取,C18净化,利用超高效液相色谱-串联三重四级杆质谱仪(UPLC-MS/MS)检测。[结果]在0.001~1.0 mg/L范围内,亚胺唑的线性关系良好,R2为0.9981(R2>0.99);在0.005、0.01、0.05、0.5 mg/kg添加水平下,亚胺唑在梨中的添加回收率为82%~98%,相对标准偏差(RSD)为4%~14%,定量限为0.005 mg/kg;亚胺唑在梨中的半衰期为16.5~16.9 d;在采收间隔期为0、14、21、28 d采收的梨中亚胺唑平均残留量分别为0.16~2.7、0.033~0.78、0.042~0.69、0.012~0.54 mg/kg;亚胺唑的国家估算每日摄入量(NEDI)为0.0055 mg,风险商(RQ)为0.9%。[结论]亚胺唑在梨中的残留量随着采收间隔期的延长逐渐降低,对一般人群健康不会产生不可接受的风险。建议在梨上使用15%亚胺唑可湿性粉剂时,最高施药剂量50 mg/L,最多施药3次,施药间隔为7 d,安全间隔期为28 d。

[Aims] This paper aims to study the residue behavior of imibenconazole on pear and evaluate the dietary risk, a method for residues analysis of imibenconazole in pears was established. [Methods] The samples were extracted with acetonitrile, purified with C18, and detected by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). [Results] The result showed all the correlation coefficient of calibration curves were over 0.99 ranging from 0.001 to 1.0 mg/L. At the level of 0.005, 0.01, 0.05 and 0.5 mg/kg, the recovery of imibenconazole in pears was 82 to 98%, RSD was 4 to 14%, and the limit of quantification was 0.005 mg/kg. The half-life of imibenconazole was 16.5 to 16.9 days;the average residue of imibenconazole in pears was 0.16 to 2.7, 0.033 to 0.78,0.042 to 0.69, 0.012 to 0.54 mg/kg of 0, 14, 21, 28 days after the last application. Given that the national estimated daily intake(NEDI) of chlorothalonil was 0.0055 mg, its risk quotient(RQ) was 0.9%. [Conclusions] The residual amount of imazole in pears gradually decreased with the extension of harvest interval, and there was no unacceptable risk to the health of the general population. Therefore, it is suggested that when 15% imidazole wettable powder is used on pears,the maximum dosage is 50 mg/L of liquid, the maximum dosage is 3 times, the interval of application is 7 days, and the safe interval is 28 days.