气相色谱法同时测定贝类中15种持久性有机污染物残留量

Simultaneous determination of 15 persistent organic pollutants residues in shellfish by gas chromatography

建立了气相色谱-电子捕获检测器(GC-ECD)同时测定贝类中15种持久性有机污染物(POPs)(包括8种有机氯农药和7种多氯联苯)残留的分析方法。采用丙酮超声提取样品中的有机氯农药和多氯联苯,提取液经液液萃取、凝胶渗透色谱和固相萃取(LLE-GPC-SPE)联合净化,采用外标法定量。结果显示,在1.0~100.0μg/L质量浓度范围内,15种持久性有机污染物均呈良好的线性关系,相关系数不小于0.9950,定量限为1.0~2.0μg/kg,检出限为0.3~0.8μg/kg,回收率在60.1%~111.0%范围内,相对标准偏差小于10%。该方法重现性好,准确度、精密度高,能满足残留分析技术要求,适用于贝类中有机氯农药和多氯联苯的同时测定。将此方法应用于检测蛤蜊、牡蛎和扇贝等贝类样品中将POPs的残留量,检出率最高的是p,p′-dichlorodiphenyldichloroethylene(p,p′-DDE),其在样品中均有检出。本研究可为进一步深入研究持久性有机污染物对水产品质量安全的影响提供技术支持。

A gas chromatography-electron capture detector(GC-ECD)method was developed for simultaneous determination of 15 persistent organic pollutants(POPs)residues in shellfish.Organochlorine pesticides(OCPs)and polychlorinated biphenyls(PCBs)residues were obtained from samples by ultrasonic extraction with acetone.And then,the extracts were purified by liquid-liquid extraction(LLE),gel permeation chromatography(GPC)and solid phase extraction(SPE)in turn.In addition,external standard method was used for quantitative analysis.The results showed that 15 POPs had a good linear relationship in the mass concentration range of 1.0-100.0μg/L,and the correlation coefficient was no less than 0.995 0.The limit of quantification was 1.0-2.0μg/kg,and the detection limit was 0.3-0.8μg/kg.The recovery rates ranged from 60.1%to 111.0%,and the relative standard deviation was less than 10%.The method has good reproducibility,high accuracy and precision,which can meet the technical requirements of residual analysis and is suitable for simultaneous determination of organochlorine pesticides and polychlorinated biphenyls in shellfish.Therefore,this method was applied to detect 15 POPs in shellfish samples,such as cockroaches,oysters and scallops.The p,p′-DDE was showed the highest positive rate and detected in all samples.The experiment will provide technical support for further in-depth study on the impact of persistent organic pollutants on the quality and safety of aquatic products.