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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 1.7×105 cfu/g to 5.7×105cfu/g for Ubeji river sediments, 1.0×105 cfu/g to 9.0×105cfu/g for spare parts dumpsite and 1.2×104cfu/g to 9.0×104 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 Pb2+, Cd2+, Fe2+, and Zn2+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.Keywords: Heavy metals, Antibiotics resistance, tolerance, Ubeji river sediments, Warri

Open scrap metallic material dumpsites or makeshift scrapyards are used in the management of collected disused metallic materials in Benin city, Edo State, Nigeria. Six topsoil samples were collected in duplicates from six open disused metallic material dumpsites located in six areas within Benin city which included; Aduwawa, Saint Saviour, Water Board, second Ibiwe, first Ibiwe and Uwelu respectively. The control soil samples were collected from the vicinity of the Faculty of Life Sciences, University of Benin. The pH and electrical conductivity (EC) of the soil samples were determined using calibrated meters. Enzyme profiling of the soil samples was conducted using standard analytical procedures which included titrimetry and colourimetric techniques. One-way analysis of variance (ANOVA) of the respective mean enzyme activities of the soil samples was conducted (α=0.05). The mean pH and EC values of the topsoil samples obtained from the dumpsites varied from 6.3 ± 0.2 to 7.8 ± 0.2 and 22.2 ± 0.5 to 107.7 ± 2.2 μ mhos/cm respectively. The mean dehydrogenase readings for topsoil from the dumpsite varied from 4.5 ± 0.4 to 8.9± 0.2 μg TPF/g soil respectively, while the control soil had a dehydrogenase activity mean reading of 1.7 ± 0.2 μg TPF/g soil The observed differences between the mean enzyme activities were significant (F = 167.062, p<0.05). It is likely that there was a link between anthropogenic land usage pattern and the edaphic enzyme profiles of the examined soil samples. It is recommended that further studies focusing on the specific nature of the soil enzymes and the microbial diversity of these contaminated topsoil niches should be conducted.

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