Pesticide residues in dates using a modified QuEChERS method and GC-MS/MS

Area of Science:

• Food Chemistry
• Analytical Chemistry
• Agricultural Science

Background:

• Pesticide residue analysis in food is crucial for consumer safety and regulatory compliance.
• Date palm fruits are a significant global food source, necessitating robust monitoring for contaminants.
• Existing analytical methods may lack the speed, efficiency, or comprehensiveness required for routine surveillance.

Purpose of the Study:

• To develop and validate a rapid, efficient, and safe analytical method for determining 198 pesticide residues in date palm fruits.
• To assess the performance characteristics of the developed method, including linearity, precision, recovery, and limits of detection/quantification.
• To apply the validated method for monitoring actual pesticide residue levels in commercially available date palm samples.

Main Methods:

• Development of a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction technique.
• Utilisation of gas chromatography-tandem mass spectrometry (GC-MS/MS) for sensitive and selective pesticide detection.
• Validation of the analytical method according to established criteria, including calibration curves, relative standard deviation, recovery rates, LODs, and LOQs.

Main Results:

• The developed QuEChERS method demonstrated high linearity (r² > 0.9934) for most pesticides within the 15-150 µg/kg range.
• The method achieved acceptable precision (RSD ≤ 20%) and mean recovery rates between 70-120%.
• Limits of detection (LODs) ranged from 5-14 µg/kg, and limits of quantification (LOQs) ranged from 14-40 µg/kg.
• Application to 30 fresh date samples revealed no detectable residues exceeding the established Maximum Residue Limits (MRLs).

Conclusions:

• The modified QuEChERS extraction coupled with GC-MS/MS is an efficient and reliable technique for analysing a wide spectrum of pesticide residues in date palm fruits.
• The validated method provides accurate and sensitive quantification, suitable for routine food safety monitoring.
• The study's findings indicate that the analysed date palm fruit samples are safe for consumption regarding the monitored pesticide residues.