Analysis of Pesticides in Citrus Oil Using a Shimadzu GCMS-TQ8030

Contamination of consumer products with pesticides is a growing concern because of recognized adverse health effects, increasing world-wide usage of pesticides, and imports of raw materials from foreign sources. Citrus oils have been used for centuries for a wide range of applications: flavor/fragrance, various medicinal purposes, and others. In recent years, new uses of citrus oils as cleaners and in aromatherapy and alternative medicine have become widespread.

Gas chromatography mass spectrometry (GCMS) has been used extensively to identify and quantify trace level pesticides in food and related matrices; the most significant challenges have been matrix interference and achievement of meaningful health-based detection limits for the compounds of interest. Triple quadrupole GC-MS/MS has emerged as a technique of choice for analysis of trace level contaminants in complex matrices. Operation of the triple quadrupole GC-MS/MS in the Multiple Reaction Monitoring (MRM) mode provides excellent sensitivity and specificity for detection and quantitation of target pesticides at low concentrations in the presence of background interferences. Most co-extracted matrix interferences are minimized using the MRM mode. The outstanding selectivity of the MRM mode has been illustrated previously.

This application note presents instrument configuration, operating parameters, and analytical results for analysis of trace levels of 47 pesticides of various chemical classes in four orange oil samples using the Shimadzu GCMS-TQ8030 triple quadrupole GC-MS/MS (Figure 1). Results were evaluated for calibration linearity, analytical precision, sensitivity, and specificity.