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In recent years, the use of agrochemicals like pesticides has caused great harm to environmental safety. Taking a site in a National Root Crops Research Institute, Umudike that use pesticides to control weed invasion and pest attack, soil samples were collected separately from each particular depth at 0-10 cm, 11-20 cm, and 21-30 cm depth at eighteen different sampling points while plant samples were collected from Zea mays, Colocasia esculenta, Manihot esculenta, and Telfairia occidentalis, and the contents of Cu, Cr, As, Ni and Zn, were tested using atomic absorption spectrometer. Results show that values of pH and organic matter in soil decreased with an increase in soil depth. A positive relationship exists between soil pH and Cu (r= 0.250), soil pH and Cr (r= 0.262), soil pH and As (0.143). A very strong positive relationship exists between soil pH and Zn in plants (r= 0.616, p<0.01), organic matter in soil and Zn in plants (r= 0.893, p<0.01) while a very strong relationship exists between electrical conductivity in soil and Cu in plants (r= 0.769, p<0.01), electrical conductivity and Cr in plants (r= 0.784, p<0.01). The mean concentration of Cu, Cr, As, Ni, and Zn in soil and plants were 3.97 and 1.82 mg/kg, 1.01 and 0.98 mg/kg, 1.68 and 0.91 mg/kg, 0.89 and 0.42 mg/kg, and 9.66 and 6.17 mg/kg, respectively. The values of As in Colocasia esculenta (0.91 mg/kg) exceeds the permissible limit of FAO/WHO. The use of such arsenic-contaminated cocoyam leaves for wrapping food items could be a route of entry of As in the human system. It is therefore recommended that Research Institute should be using bio-pesticide such as Azadirachta indica oil (Azadirachtin) and fungi of the Metarhizium acridum family that have been approved by FAO/WHO for control of weed and insect pests.