BACTERIOLOGICAL AND PHYSICOCHEMICAL ANALYSIS

ABSTRACT

This study was carried out to evaluate the bacteriological and physicochemical properties of water samples from three hospitals in Benin City. Standard physicochemical and microbiological methods were used for analyses of water samples. pH, electrical conductivity, salinity, nitrate, phosphate and heavy metals were evaluated for the samples. While membrane filtration and culture techniques were used for microbiological analyses. Antibiotic susceptibility was carried out using Kirby-Bauer disk diffusion method and the multiple antibiotic resistance index was evaluated.  The results showed pH values ranged from 7.04±0.00 – 7.11±0.01. The salinity values ranged from 17±0.58 -18±0.00mg/L. Temperature values obtained for water samples ranged from 27.00±0.00 - 27.50±0.00^oC. The heavy metal contents for lead and cadmium were found to be below detectable limits (0.00±0.00) for all tested samples obtained from hospitals. The bacterial counts ranged from log₁₀ 0.78±0.00 cfu/100ml to log₁₀ 4.05±0.14 cfu/100ml. The coliform counts obtained ranged from log₁₀ 0.00±0.00 cfu/100ml to log₁₀ 3.63±0.14 cfu/100ml. the identified bacteria isolates were Bacillus subtilis, Enterobacter aerogenes, Serratia marcescens and Micrococcus luteus. The phenotypic virulence characteristics of the isolates revealed that all isolates were positive for at least one of the properties tested and as such are potential pathogens of clinical significance. The antibiotic susceptibility showed that most isolates were resistant to erythromycin, tetracycline and sulfamethoxazole. The multiple antibiotic resistance index of the isolates revealed that all isolates had MAR index greater than 0.2 and thus they are of public health importance.