Occurrence of pesticide residues in imported and locally-grown crops as analyzed by gas chromatography mass spectrometry

Food safety is gaining prominence as a global issue. Consumers are frequently notified of health concerns associated with imported foods as well as specific fruits and vegetables. Pesticide residues in 111 random samples, including 6 different crops as 28 samples of potatoes, 22 samples of oranges, 34 samples of onions, 13 samples of chilies, 12 samples of apples and 3 samples of grapes from selected growing areas and imported consignments at Orugodawatta, Sri Lanka were evaluated against 12 pesticides Samples were extracted according to the quick, easy, cheap, efficient, rugged, safe (QuEChERS) method as per Association of Official Analytical Chemist (AOAC) official method 2007.01. Concentrated samples were achieved by Gas Chromatography Mass Spectrometry (GC-MS) in Selective Ion Mode (SIM). Recovery studies at three spiking concentration levels as 1 Limit of Quantification (LOQ), 5 LOQ and 10 LOQ, varied from 70 % to 110 %, with a Relative Standard Deviation (RSD) below 20%. Among the imported samples that were positive for pesticide residues, Diazinon, Chlorphyrifos, Fipronil, Oxyfluorfen, Tebuconazole were detected in 5.56%, 1.85%, 14.81%, 16.66 %, 12.96 % samples, respectively and among the local samples that were positive for pesticide residues, Pendimethalin, Pretilachlor, Bifenthrin, , Chlorphyrifos, Fipronil, , Oxyfluorfen, Tebuconazole were detected in 2.77%, 2.77%, 22.22%, 1.75%, 12.28%, 17.54%, 7.01% respectively. The results revealed the presence of pesticide residues in both imported and local samples between the range of 0.044 ppm to 6.57 ppm. Continuous monitoring of pesticide residue in imported crops and those grown in Sri Lanka need to be conducted to obtain sufficient evidence to make conclusive policy decisions to ensure consumer safety.