Rapid monitoring of pesticides in tomatoes (Solanum lycopersicum L.) during pre-harvest intervals by paper spray ionization mass spectrometry.

A rapid analysis of acephate, chlorpyrifos, and cyazofamid in tomato peels during pre-harvest intervals using paper spray ionization mass spectrometry (PSI-MS) has been demonstrated. LODs of 0.01 ppm and LOQs of 0.03 ppm were achieved. Relative standard deviations were below 9%, and recoveries close to 100%. For pesticides monitoring, samples were separated into stored and field groups. Stored group contained fruits that were harvested and stored at low temperature during the pre-harvest interval, and the field group contained fruits that were on the agricultural field over the pre-harvest interval. The decrease in pesticide amounts was lower for the stored samples. At the end of the pre-harvest intervals, acephate, chlorpyrifos, and cyazofamid were determined at 0.86, 0.96, and 0.23 ppm in the stored group, and at 0.26, 0.37, and 0.09 ppm in the field group, respectively. This work demonstrates the utility of PSI-MS for performing rapid quality control of fruit harvesting.