This work investigated the antibiotic resistance patterns and heavy metals such as
Lead (Pb), Zinc (Zn), Cadmium (Cd) and iron (Fe) tolerance of selected bacteria isolated from
contaminated soils and sediments around Warri area of Delta State. The heterotrophic bacterial
counts for the sampled soils and sediments ranged from 1.7×10
5 cfu/g to 5.7×10
5cfu/g for Ubeji
river sediments, 1.0×10
5 cfu/g to 9.0×10
5cfu/g for spare parts dumpsite and 1.2×10
4cfu/g to
9.0×10
4 cfu/g for Ifie depot sites respectively. The characterized bacterial isolates included;
Klebsiella
sp,
Bacillus subtilis
,
Streptococcus
sp.,
Escherichia coli
,
Klebsiella mobilis
and
Staphylococcus
sp.,
Micrococcus
sp. and
Pseudomonas aeroginosa
.
Bacterial isolates showed
multiple drug resistance and the most resistant isolates were
S. aureus
,
E. coli
and
P. aeroginosa
while
K. mobilis
exhibited the least resistance. The tolerance of the bacterial isolates exposed to
varying concentrations of Pb
2+, Cd
2+, Fe
2+, and Zn
2+was ascertained using agar diffusion method.
All the bacterial isolates exhibited varying degree of susceptibility at different concentrations of
Pb and Cd while the organisms displayed abundant and moderate growth in the presence of Fe
and Zn even at higher concentrations. The ability of these bacteria to resist antibiotics and heavy
metal tolerance could present serious danger to the environment as the resistance genes may be
transferred to surrounding wild type microbial cells.
