Extended Spectrum Beta-Lactamases (ESBLs) encoding genes (TEM, SHV and OXA) were amplified from multidrug resistance E. coli. The multidrug resistance E. coli isolates from different clinical sources were documented to be plasmid encoded and resistance against β-lactam and cephalosporin. Conventional laboratory analysis showed that seventy percent (70%) of the selected multidrug resistant clinical isolates were ESBLs positive, showing a ≥5 mm increase in zone diameter for either antibiotics compared to its zone when tested alone. The antibiotic susceptibility result showed that 100% of the isolates were resistant to amoxicillin-clavulanic acid, amoxicillin, cefuroxime and ampicillin-sulbactam while 90% of the isolates were resistant to ceftazidine and tetracycline, 80% to ofloxacin, 70% to ceftriazon, nalidixic acid, cefalexin, 60% to ciprofloxacin, 50% to nitrofurantoin, 40% to chloramphenicol and 20% to gentamicine. The multiplex PCR with primers TEM (931bp), SHV (868), OXA-2 (478), aac(3)-IIa (900) and rmtA (634), which are genes responsible for extended spectrum β-lactamase and aminoglycoside resistance in E. coli shows that: isolate W15 comprises of three (3) resistant gene, which corresponds with TEM resolving as a 931 base pair, SHV 868 base pair, and a 478 bp indicating OXA-2 that is faint probably indicating a low concentration of the gene. Isolate B2 comprises single resistant gene, which is interpreted as OXA-2 with 478 base pair while isolate URO2, U64 and S45 comprises of two resistance genes which resolve as 868 and 478 base pair indicating SHV and OXA-2 respectively. However, isolates S57, U58 and B7 showed no gene amplification despite the various degree of resistance in MIC and * Corresponding author. J. C. Igwe et al. 277antibiotic susceptibility profile test obtained with conventional detection analysis. We assume that their resistant genes are not coded for by the primers used in this study as these isolates are likely to contain other resistant genes, which are also expressed at a molecular level. This study stands to show that molecular characterization has a great correlation with analytical methods.

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Plastic packaging materials constitute a major potential environmental pollutant due to their slow degradation rates. This study aimed to isolate the plastic-degrading bacteria from the solid waste dumpsites of Abuja, Nigeria. Soil samples (n= 72) and plastic materials (bottles and bags) were collected from the dumpsites using soil augers and manual picking, respectively. Bacteriological analysis of the soil samples revealed the recovery of a total of 54 bacterial isolates, which were distributed among the genera of; Proteus sp. ( 33.3 %), Providencia sp. (29.63 %), Pseudomonas sp. (16.67 %), Bacillus sp. (9.26 %), Micrococcus sp. (5.56 %), Escherichia coli (1.85 %), Enterobacter sp. (1.85 %), and Serratia sp. (1.85 %).The bacterial isolates were inoculated into a series of shake flasks containing nutrient broth and pre-sterilized strips (1×1 cm) of plastic bags (0.05-0.0514 g) and plastic bottles (0.05-0.0529 g), and then incubated at 30 o C for 60 d to monitor their biodegradation using the weight loss method. The strips of bottles (0.58-49.00 %) were more susceptible to biodegradation than the plastic bags (0.78-15.40 %) after 60 d of incubation. The results demonstrated that about 6 of the bacterial isolates belong to the two genera of Proteus sp. and Providencia spp., and were considered the best bio-degraders. Molecular characterization of these potent isolates has identified them as Proteus mirabilis strain PPB3 (49.00 %), Proteus mirabilis strain UPMSD3 (32.07 %), Proteus mirabilis strain HH133 (20.41 %), Proteus mirabilis strain SSBIKEN (15.40 %), Providencia vermicola strain M4 (14.96 %), and Providencia vermicola strain 11 (12.20 %). These strains could be considered as potential biodegradation agents for the plastic materials that are prevalent in dumpsites.

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The environmental risks associated with heavy metal pollutions are becoming worrisome. Hence, this study evaluated the environmental and human health risks of lead (Pb) accumulation in soil samples from solid waste dumpsites within Abuja, Nigeria. Soil samples (n=72) were collected (0-45 cm depth) from Abaji, Bwari, Gosa, Gwagwalada, Kuje, and Kwali dumpsites and 2 km away (control), and then analyzed for Pb using atomic absorption spectrophotometer. The risks of Pb contaminations were then evaluated in soils and in individuals (Children and Adults) via inhalation and dermal contacts with soil using ecological and health risk equations. Pb concentrations in the dumpsites were below the permissible limits set by environmental protection agencies and were highest in Kuje dumpsite and lowest in Abaji dumpsite. The ecological pollution indices ranged from ‘low risks’ (at Bwari, Gosa, Gwagwalada dumpsites) to ‘very contamination risks’ (at Kuje and Kwali dumpsites). Daily dose for Pb via dermal contact pathways were higher and no significant lifetime health (non-carcer and cancer) risks were observed suggesting that inhalation and dermal routes pose very low health risk of Pb poisoning in both children (≤ 15 years) and adults (≤ 70 years). This study suggests that the concentration of Pb in the study dumpsites might cause more ecological risks than health hazards in exposed individuals via inhalation and dermal pathways.