A versatile modified QuEChERS-LC-MS/MS method for determination of 102 pesticide residues in diverse dried aquatic product matrices and dietary risk assessment.

Pesticide residues in dried fish, originating from both processing and raw materials, remains a neglected safety risk, while the high protein and fat content of the matrix renders rapid and accurate residue analysis challenging. A modified QuEChERS method was developed for simultaneous analysis of 102 pesticide residues in dried aquatic products. The optimized extraction process was performed using 5 mL of acetonitrile containing 0.25% formic acid, followed by purification with 50 mg primary secondary amine (PSA) and 10 mg octadecylsilane (C18) as co-sorbents. The optimized method demonstrated satisfactory analytical performance, including good linearity (R2 ≥ 0.9926), acceptable recoveries (65.5%-122%), satisfactory intra-day and inter-day precision (RSDs < 20%), and high sensitivity (LODs: 0.01-1.1 µg/kg; LOQs: 5 µg/kg). To verify its practical applicability, the method was evaluated for the analysis of pesticide residues in ready-to-eat or not ready-to-eat freshwater and marine products. The majority of pesticides exhibited acceptable recoveries, confirming its suitability for determining multi-pesticide residues in dried aquatic products. Subsequently, when the method was applied to 125 commercial dried fish samples, a total of 27 pesticides were detected, with concentrations ranging from 0.1 to 20.59 µg/kg. These results confirm that the developed method is robust, sensitive, and suitable for multi-residue monitoring of pesticides in complex processed aquatic products, covering the main types of commercially available dried fish. Importantly, the exposure risks of the detected pesticides were acceptable for humans, providing a scientific basis for the dietary exposure risk assessment of dried aquatic products.