Development and application of a rapid screening and quantification method for multi-class herbicide residues in fishery products using UPLC-Q-Tof-MS/MS: Evidence for prometryn residues in shellfish

Quality and safety issues arising from herbicide residues in fishery products are a growing concern. In order to ensure the edible safety of fishery products, a comprehensive assessment of multi-class herbicide residues should be conducted. Hence a modified QuEChERS approach was explored and validated using UPLC-Q-Tof-MS/MS for rapid screening and quantification of 158 herbicide residues in fishery products. An efficient lipid-removing sorbent, EMR-Lipid, was employed instead of the conventional QuEChERS dispersive sorbents like PSA or C18. The method performed well in assessments of linearity, sensitivity, recovery and reproducibility with correlation coefficients over 0.992, LODs below 3.0 μg kg−1 for most analytes (98.7%), recoveries ranging from 61.2 to 128.4% and RSDs less than 20%. Moreover, the technique was applied to determine the fragment ions of 158 herbicides as fingerprints for accurate identification. And then the fragmentation pathways of eight categories of herbicides were deduced from the interpretation of fragment ion structures as a means of quickly distinguishing between herbicide classes in the absence of standards. The methodology was successfully applied to analyze 95 crustacean and shellfish samples from Hubei, Hunan and Zhejiang provinces of China. Only shellfish samples such as green clams and razor clams were screened for residues of the triazine herbicide prometryn. Based on the results, the potential risk of prometryn in shellfish should be paid much more attention.