Level of Selected Precedence Pollutants in Soils of the Industrial Regions of Welmera District (Oromiya Special Zone around Finfinne), Ethiopia

Abstract

Farm soils of Oromiya special zones around Finfinne in general, Welmera district in particular are recently become polluted through the continuous and intensive applications of pesticides apart from contamination by heavy metals from various sources. In the present study, soil samples collected from different sites of industrial regions in the Welmera district were tested for organochlorine pesticides (OCP) and heavy metals concentration and distribution using GC-MS and AAS respectively. The result shows that the value of heptachlor ranges from (ND-0.88±0.014), methoxychlor (ND-2.14±0.06), chlordane (0.07±0.002-0.98±0.023),DDT(o,p’-DDT+p,p’-DDT)(ND- 0.88±0.02), endosufan(α) (0.53±0.01-3.05±0.07)mg/kg and As (0.436±0.022-7.29±0.008), Co(ND-15.13±0.022), Cr(ND-107.44±0.17), Ag(ND-1.06±0.008), Cd(ND-52.08±0.046), Ni(0.99±0.005-121.23±0.021)mg/kg in dry soil. The present result reveals that the farm soils contain a significant amount of these chemicals. The polluted soils can act as a secondary source of pollutants which makes the problem more complex. The current work provides new information regarding the levels of both selected persistent organochlorine pesticides and heavy metals in soils of Welmera district and therefore, it is very important to work on reducing the impact of these chemicals upon the environment. Based on the study result, specific regulations and restrictions upon pesticide use, making agricultural policies reform in order to encourage patterns of land use, farming practices, monitoring anthropogenic sources of heavy metals and uses of inputs which are in better concord with the environment are strongly recommended.