Residue determination and risk assessment of benziothiazolinone in citrus by LC-MS/MS

A quick, easy, cheap, effective, rugged and safe liquid chromatography-tandem mass spectrometry technology was used to determine benziothiazolinone in citrus. Orthogonal test and single-factor analysis were conducted to identify the optimal extraction method of benziothiazolinone. The good linearity (R2 > 0.9949), high accuracy and precision, matrix effect and satisfactory recoveries (79.31%–98.68%) at three spiked levels (0.02, 0.2 and 2 mg/kg) with low relative standard deviation values (0.63%–8.68%) were validated. The limits of detection and quantification were within 0.2–0.8 and 20 μg/kg, respectively. This study could provide guidance for the reasonable use of this fungicide and for the establishment of maximum residue level.