Target and suspect screening approaches for the identification of emerging and other contaminants in fish feeds using high resolution mass spectrometry

Fish feed is essential in aquaculture fish production because, along with beneficial nutrients and components, many suspected compounds can be transferred to fish and ultimately to humans. In this context, a comprehensive analysis was conducted to monitor various pesticides and pharmaceutical compounds in aquaculture fish feed through target analysis and many other groups of chemicals via suspect screening approaches. In this study, the QuEChERS extraction method was optimized, validated, and applied to fifty-four fish feed samples collected from different production batches. This was followed by liquid chromatography-high-resolution linear ion trap/Orbitrap mass spectrometry (LC-HR-IT/Orbitrap-MS) for targeted and suspect screening purposes. In general, pesticides provided satisfactory recoveries (70–105.5 %), with quantification limits lower than 5 ng g−1, whereas pharmaceuticals displayed recoveries ranging from 70.5 to 120.2 %, with quantification limits below 25 ng g−1. In addition, the matrix effects and measurement uncertainty were assessed to provide more accurate and high-confidence results. Pirimiphos-methyl was detected and quantified in 20 of 54 fish feed samples (37 %) at concentrations