Physicochemical Characteristics and Microbial Quality of an Oil Polluted Site in Gokana, Rivers State.

Abstract

Samples were collected from the soil surface area, the water surface, sub-surface sediment sand, sand from the river shore, Dead Sea food and dead mangrove vegetation leaves. Test results indicated that the Total Heterotrophic Bacteria (THB) values ranged from (9.0 ~ 103 . 2.6 ~ 106) cfu/ml with the sample from the water surface having the highest value (2.6 ~ 106) cfu/ml and the least with the sample from the sub-surface (9.0 ~103) cfu/g. The Total coliforms values ranged from (6.9 ~ 103 . 2.3 ~ 106) cfu/100g with sample from the dead vegetation leaves having the highest value (2.3 ~ 106) cfu/100g and the least value from the sample from mangrove substrate(6.9 ~ 103) cfu/100g. Among the physico-chemical parameters tested, TDS, lead, copper, chromium, cobalt, zinc, cadmium, nickel and arsenic were within acceptable limits as specified by regulatory agents. However, electrical conductivity, oil and grease, and iron were very high and above specified limits. The pH values ranged from 3.90 .8.15 with the sample from the mangrove substrate having the highest value (8.15) and the lowest value was from the sample from the crude on water surface (3.90). The electrical conductivity values ranged from (1275 . 3565) ƒÊS/cm with sample from crude band on soil surface having the highest value (3565)ƒÊS/cm and the lowest value from thesample from the sub-surface sediment sand (1275) ƒÊS/cm. The oil and grease values ranged from (620 . 32040) mg/kg with sample from soil surface having the highest value (32040) mg/kg and the lowest value from the river shore sand (620) mg/kg. The high level of oil and grease contamination poses a concern. This therefore, validates theconcern that releases of large quantities of oil to aquatic and terrestrial environments present a long term threat to all forms of life