DETERMINATION OF ORGANOCHLORINE PESTICIDE RESIDUES IN SOIL, FRESH AND DRIED TOMATOES FROM SELECTED FARMLANDS IN GUSAU, ZAMFARA STATE, NIGERIA

Abstract

In this study, organochlorine pesticide (OCP) residues in fresh, dried tomatoes and soils from selected farmlands in Gusau, Zamfara State, Nigeria were determined. QuEChERS and GC-MS were used for sample preparation and analysis, respectively. The results obtained shows the presence of OCPs residues namely; α- lindane, endosulfan I, isodrin, heptachlor, DDMU, and dieldrin with concentration of 1.669 mg/kg, 1.183 mg/kg, 0.129 mg/kg, 0.032 mg/kg, 0.0067 mg/kg, 0.037 mg/kg, in fresh sample A while endosulfan I, isodrin and dieldrin with concentration of 0.027 mg/kg, 0.003mg/kg and 0.025 mg/kg were detected in dried sample A. α- lindane, endosulfan I, and isodrin were above the maximum residual limits (MRLs) in the fresh samples, all below the MRLs in dried samples A, while δ- pent, α- lindane, β-lindane, endosulfan I and II, isodrin, dieldrine, and DDMU were detected in fresh sample B, with concentration of 0.012 mg/kg, 2.77 mg/kg, 0.010 mg/kg, 0.171 mg/kg,0.005 mg/kg, 0.129 mg/kg, 0.078 mg/kg, 0.273 mg/kg and 0.007 mg/kg, respectively. Only α lindane, endosulfan I, isodrin, dieldrin, and DDMU with concentration 0.023 mg/kg, 0.102 mg/kg, 0.013 mg/kg, 0.013 mg/kg and 0.001 mg/kg were detected in dried sample B. Concentration of α lindane, endosulfan I, and isodrin were above MRL in fresh samples B, below the MRLs in dried samples B. α-lindane, β-lindane, endosulfan I and II, Isodrin, and DDMU were detected in fresh samples C with concentration of 2.160 mg/kg, 0.008 mg/kg, 0.168 mg/kg, 0.007 mg/kg, 0.187 mg/kg, and 0.031 mg/kg, respectively. α- lindane, endosulfan I and II, isodrin and DDMU with concentration of 0.01 mg/kg, 0.0152 mg/kg, 0.003 mg/kg, 0.048 mg/kg and 0.003 mg/kg were detected in dried samples C. α-lindan, Endosulfan I, isodrin and DDMU were above MRLs in fresh sample C, but below the MRLs in dried samples C. All the OCPs detected in the soil samples are below the MRLs except α- lindane and endosulfan I, with concentration of 0.626 mg/kg and 0.069 mg/kg, which are above the MRLs in soil sample A. On the other hand α- lindane and heptachlor has hazard index of 2.737 and 1.012 respectively. Therefore, the level of OCP residues were lower in the dried tomato samples compared to the fresh samples, while α- lindane and heptachlor pose a potential health risk since the hazard index is equal and greater than 1.