BACTERIOLOGICAL CHARACTERIZATION OF SOILS AND LEACHEATES FROM MUNICIPAL DUMPSITES IN BENIN CITY, NIGERIA

Abstract

Bacteriological and physiochemical analysis were carried out on soil and leacheates using standard scientific methods. A total of 80 samples (soil and leacheates) from waste dumpsites were obtained from 4 sites in Benin City; (University of Benin, Costain Road, University of Benin Teaching Hospital and Government Reservation Area dumpsites). Standard microbiological methods were adopted for bacteria isolation, characterization and identification. Bacillus cereus, Bacillus subtilis, Klebsiella aerogenes, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa and Proteus mirabilis were identified from the specimens. The most prevalent isolates from environmental waste were B. subtilis, K. pneumoniae and B. cereus (50% each) while the least were P. aeruginosa, E. coli, P. mirabilis and K. aerogenes (5% each). Bacterial viable count was highest in soil (1.92 X 106 cfu/g) from Costain dumpsites while from leachate samples, bacterial burden was highest in Uniben dumpsite (1.79 X 106 cfu/ml). Physico-chemical analysis of soil and leachate from the four dumpsites included test for pH, electrical conductivity, total dissolved solute, calcium, magnesium, sodium, potassium oxide, nitrogen oxide, chloride, sulphates, carbon, nitrogen, phosphorus, potassium, ammonium chloride, silt and clay. Soils from all dumpsites appeared generally sandy. Statistical analysis was performed using two-way analysis of variance (ANOVA) to locate significant microbial load of micro organisms obtained from dumpsites. Results revealed that there was significant difference between microbial loads in dumpsites (P<0.001).