IMPACT ASSESSMENT OF CRUDE OIL WELL ON MANIHOT ESCULENTA (CRANTZ) AND QUALITY OF SURROUNDING SURFACE WATER BODIES
Anthony Ojekale1, Chionyedua Onwordi2, Patrick Akas3, and Malik Lasisi4
1Lagos State University, Nigeria, 2Lagos State University , Nigeria, 3Lagos State University , Nigeria, and 4Lagos State University , Nigeria
Background: Exploration/exploitation of crude oil has impacted positively on the Nigerian economy and negatively on its environment. This study assessed the impact presence of an oil well has on Manihot esculenta and quality of surface water in Aguleri, South Eastern Nigeria.
Results: Cassava proximate results; moisture content (5.25), carbohydrate (71.38%), crude protein (9.10%), crude fibre (5.20%), ash content (4.01%) and crude fat (1.56%). Copper concentrations (13.8 mg/kg, WHO, 73.30mg/kg), Nickel (3.2 mg/kg, WHO, 67.9mg/kg), cadmium (0.2mg/kg WHO, 0.2mg/kg), all within permissible levels in Manihot esculenta, while Iron (158.5mg/kg, WHO 50mg/kg), manganese (7.0mg/kg, WHO 2mg/kg), chromium (6.1 mg/kg, WHO 0.05mg/kg), cobalt (2.5 mg/kg, WHO 0.1mg/kg) and lead (1.8 mg/kg WHO 0.3mg/kg) concentrations were higher than the WHO allowable levels. All parameters analyzed in water samples; (pH, 7.05; WHO, 6.5-8.5) (conductivity, 62.30 µs/cm, WHO 500 µs/cm) (turbidity, 3.3 NTU, WHO <5) (total dissolved solids 31.50 mg/l WHO, 500mg/l), (total suspended solids, 100mg/l, WHO 500mg/l) and (nitrate, 0.5 mg/l, WHO 50mg/l) were within WHO allowable limit. Manganese and cobalt concentrations in water sample were within allowable limits, while Iron, chromium, nickel and lead (two sampling points) were not. Ash values of cassava analyzed was high.
Conclusion: Water and cassava sampled have high concentrations of heavy metals, probably due to contamination from crude oil exploration and/or oil spillage. This study recommends portable water for communities close to oil well for domestic use/irrigation. Furthermore, farming activities should be in areas far removed (>19.4km) from the oil well to mitigate contamination of surface waters and farm produce.
Oil well, Water, Manihot esculenta, and Proximate analysis