Int. J. Biosci.3( 8), 40-48, August 2013
The effect of composition on the biodegradability and toxicity of two muds commonly used at onshore oil fields at Ologbo, Edo State were examined. Biodegradation of drill muds by two bacterial and fungal isolates; Enterobacter aerogenes, Micrococcus sp., Aspergillus sp. and Penicillium sp. were carried in a shake flask experiment using mineral salts medium at 120 rpm for 28 days. The total viable counts were monitored and ultimate biodegradability was derived from the ratio of COD and BOD5, after every four days. Lethal effects of the drilling muds on juvenile Tilapia guineensis, Micrococcus sp. and Penicillium sp. were investigated using static renewal bioassay for 96 hr and 24 hr. The Potassium chloride (KCl) polymer water based mud (WBM) was more biodegradable than synthetic based mud (SBM). This was indicated by the highest total viable counts recorded in consortium amended with water based mud (101 ×103 cfu/ml), and also recording the lowest chemical oxygen demand and biological oxygen demand (47 mg/l and 0.4 mg/l respectively).There were no significant differences (P > 0.05) in the degradation of the muds by the isolates. The 96 hr LC50 of potassium chloride (KCl) polymer water based mud and synthetic based mud (SBM) were 8125 mg/l and 5800 mg/l for Tilapia guineensis respectively. The 24 hr LC50 of Potassium Chloride polymer water based mud was 200 mg/l for Micrococcus sp. and Penicillium sp. Exploration and production companies operating in Ologbo should be encouraged to put into consideration the effect composition of the drilling muds before usage.
Alan HD, David H, Deborah JR. 2006. Biodegradation of synthetic based fluid surrogates in the Gulf of Mexico sediments. Environmental Science Technology 40(18), 5737 – 5742. http://dx.doi.org/10.102/es060873e
American Public Health Association (APHA). 1998. Standard Methods for the Examination of Water and Waste Water. American Public Health Association, 20th ed. Washington D.C.
Barnett HL, Hunter BB. 1975. Illustrated Genera of Imperfect Fungi 3rd ed. Burgess Publishing Company. Minneapolis.
Buchanan RE, Gibbons NE. 1974. Bergey’s Manual of Determinative Bacteriology. 8th ed, Williams and Wilkins Co. Baltimore.
Cheesbrough M. 2000. District Laboratory Practices in Tropical Countries Part 2. Cambridge University Press, London.
Department of Petroleum Resources (DPR). 2002. Environmental Guidelines and Standards for the Petroleum Industry in Nigeria (EFAPSIN). DPR, Abuja.
Dutton RJ, Bitton G, Koopman E, Agami O. 1990. Effects of environmental toxicants on enzymes biosynthesis: a comparison of β-galactosidase and α-glucosidase and tryptophanase. Archives of Environmental Contamination and Toxicology 19(3) 395 – 398.
Engelhardt FR, Ray JP, Gillam AH. 1989. Drilling waste. Proceedings of the 1988 International Conference on Drilling wastes. Calgary, Alberta, April 1988. Elsevier Applied Science, London and New York. ISBN.1851662782
Ekpo M, Ekanem AIJ. 2000. Toxicity of petroleum drilling mud additive (chrome lignosulfonate) on micro-organisms and fresh water fish tilapia (Oreochromis nilotieus). Nigerian Journal of Microbiology 14(2), 55 – 60.
Imarhiagbe EE. 2012. Microbiology and biodegradability of drill mud cuttings at Ologbo, Edo State, Nigeria. PhD Thesis University of Benin, Nigeria. 186 p.
Neff JM, McKelvie S, Ayers RC. 2000. A literature review of environmental impacts of synthetic based drilling. Report to U.S Department of Interior Minerals Management Service. Gulf of Mexico OC Office New Orleans, LA. 154.
Organization for Economic Co-operation and Development (OECD). 1995. Detailed Review Paper on the Test Guidelines Programme OECD, Paris.
Odokuma LO, Akponah E. 2008. Response of Nitrosomonas, Nitrobacter and Escherichia coli to drilling fluids. Journal of Cell Animal Biology 2(2), 043 – 054
Odokuma LO, Ikpe MD. 2003. Role of composition on the degradability and toxicity of drilling muds. African Journal of Applied Zoology and Environmental Biology 5, 6 – 13.
Okerentugba PO, Ezeronye OU. 2003. Petroleum degrading potentials of single and mixed microbial cultures isolated from rivers and refinery effluent in Nigeria. African Journal of Biotechnology 2(9), 288 – 292
Okoro C. 2011. Aerobic degradation of synthetic based drilling mud base fluids by Gulf of Guinea sediments under natural environmental conditions. Life Science Journal 8(2), 569 – 576
Okpokwasili GC, Okorie BB. 1988. Biodeterioration potentials of micro-organisms isolatedfrom car engine lubricating oil. Tribol International 21(4), 215 – 220.
Vincent-Akpu IF, Sikoki FD, Utibe D. 2010. Toxicity of drilling fluid XP-07 to Tilapia guineensis fry. African Science 9(2), 68-76.