Mitigating the impact of organochlorine and pyrethroid residues in fresh and chemically washed spinach

Abstract

Spinach is highly contaminated with different pesticide residues. This study was designed to evaluate organochlorine and pyrethroid pesticide residues present in various washing treatments (T₀-T₁₃) of fresh and chemically washed spinach with respect to maximum residues limits. Efficiency of washing solutions (citric acid, acetic acid, garlic extract and ginger extract) of different concentrations (w/v %) along with tap water in spinach was investigated for residues dissolution. Results showed that the highest reductions in endosulfan, deltamethrin and cypermethrin residues were 0.008 ± 0.008 mg.kg^-1 (53%), 0.023 ± 0.024 mg.kg^-1 (76%) and 0.017 ± 0.014 mgkg^-1 (83%) in treatment of T₅ (10% acetic acid) followed by 0.035 ± 0.029 mg.kg^-1 (50%), 0.051 ± 0.029 mg.kg^-1 (73%) and 0.037 ± 0.048 mg kg^-1 (81%) in treatment T₁₁ (10% ginger extract) while the lowest reductions in residues were 0.304 ± 0.004 mg.kg^-1 (23%), 0.432 ± 0.030 mg.kg^-1 (35%) and 0.468 ± 0.016 mg kg^-1 (38%) in treatment T₂ (5% citric acid), respectively. In conclusion, 10% acetic acid, ginger extract and mixture of acetic and citric acids can effectively minimize pesticide residues in treated spinach.

Keywords:
spinach; endosulfan; cypermethrin; deltamethrin; gas chromatography; washing treatments