Traceable and Integrated Pesticide Screening (TIPS), a Systematic and Retrospective Strategy for Screening 900 Pesticides and Unknown Metabolites in Tea

Pesticide management is a crucial issue for sustainable agriculture and food safety. The high-resolution mass spectrometry (HRMS)-based screening method has become a popular choice to monitor pesticide residues in foods and the environment. Data-independent acquisition (DIA) was the first option allowing for this type of analysis due to the wide compound coverage compared to traditional targeted analysis using triple-quadrupole tandem mass spectrometry (QqQ). However, a higher false-positive detection rate is a critical shortcoming in DIA. To overcome this concern, a rigorous method is needed to determine the reliable information acquired from DIA screening. A systematic strategy, traceable and integrated pesticide screening (TIPS), was proposed in this study to comprehensively monitor pesticides and metabolites in a complex tea matrix, avoiding false-positive detection. A total of 900 pesticides were added to an in-house database and evaluated through precision tests, which showed good repeatability and reproducibility. One hundred pesticides and metabolites were detected and confirmed by TIPS in 98 commercial tea samples. In addition to the authorized pesticides that could be detected in TIPS, chlorfluazuron, diafenthiuron, and tolfenpyrad, which are pesticides not allowed to be used in tea farming, were frequently found in this study. In addition, dinotefuran DN and fenbuconazole metabolites RH-9129 and/or RH-9130 were tentatively identified in the archived data using retrospective analysis. The HRMS-based data in TIPS could be a record platform for tracing novel or emerging contaminants not initially targeted in samples. TIPS, a novel strategy, has great potential for rapidly conducting a risk assessment of unexpected pesticides in food.