Monitoring of Pesticide Residues in Brinjal

Abstract

Pesticides are toxic chemicals used in agriculture sector to control crop losses due to insect-pest infestation. However, if good agriculture practices are not observed, these chemicals may cause pesticide residues issue. Pesticide residues analysis is a tedious and expensive job. Brinjal crop is grown on 8427 hectares area with an average production of 84255 tones. This crop suffers from many insect/pests which cause diseases like root rot, soft rot, wilting, russeting, damping off, fruit rot, bacterial wilt, leaf rot, mosaic and collar rot and different types of pesticides are used to control them. In the present study, brinjal samples marketed in Rawalpindi and Islamabad from different parts of Punjab were collected and analyzed for pesticide residues. Hence, the study reports the status of pesticide residues in brinjal samples and assess its health implications in the area. Total 25 brinjal samples were prepared by using QuCHERS method, analyzed on capillary GC µECD and the positive samples were confirmed on GC-MSD. About 88 percent samples were containing pesticide residues among which 20 percent samples were exceeding the European Union and Codex Alimentarious Commission (EU and CAC MRLs). Chlorpyrifos was identify in 20 percent samples ranging from 0.2-5.7 mg/kg. λ-cyhalothrin was identified in 88 percent samples with concentration ranging from 0.001-0.14 mg/kg. α-Endosulfan and β-Endosulfan were not detected in any sample however, its 3rd isomer Endosulfan sulphate was detected in 24 percent samples but below LOQ. It illustrates the persistence nature and uptake of this compound from previous applications. The calculated human health risk indices show that there is no risk from pesticide residues except chlorpyrifos present in brinjal. Chlorpyrifos aHI for male and female is 1.78, 1.98 while cHI is 1.87, 2.07 and λ-cyhalothrin aHI is 0.05, 0.056 and cHI is 0.017, 0.018 respectively. Furthermore, the health risk from chlorpyrifos in brinjal was higher for females than males. This study concludes that low levels do not remain low forever, hence good agriculture practices (GAP) should be observed and the produce should be regularly monitored for pesticide residues. Moreover, there is lack of reliable public food consumption statistics for risk assessment.