Spent engine oil and industrial effluent induced heavy metals and changes in soil and air potato quality

This study was conducted to investigate the effects of spent engine oil and industrial effluent on the soil and Dioscorea bulbifera plant. Spent engine oil (SEO) was added to the buckets filled with 15 kg of loamy soil at different volumes of 0 , 75 , 225, and 375mL. Another bucket was filled with 15 kg of industrial effluent (IE). The results showed that SEO in soil has highly significant (p ≤ 0.05) effects on some of the soil's physicochemical properties. Industrial effluent (IE) had the highest nitrogen content (0.89%) while the lowest was in 75 mL15kg-1 (0.72%). pH was higher in control (4.29) and the lowest was at 375 mL15kg-1 (4.89). The chlorophyll content range was 274.06 mg g-1 (IE) – 349.60 mg g-1 (control). Also, bulbils from IE had the least fresh and dry weight (20.21 g and 14.73 g, respectively). The bioaccumulation factor (BAF) of all heavy metals examined was less than 1, except for copper. Heavy metal uptake order by the bulbil is Cu > Fe > Zn > Pb. Considering the detrimental effects of SEO and IE pollution on soil and plants, it has become necessary for the government to have a policy that will prevent indiscriminate disposal of waste.