Physico-chemical and microbial quality assessment of stored and source household waters from Osun, Oyo and Lagos State
Date
2015
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Microbiology,Obafemi Awolowo University
Abstract
This study was designed to determine the physicochemical and microbial quality of household stored and source water in Osun, Lagos and Oyo States, Southwestern part of Nigeria. This was with a view to obtain the frequency of pathogenic fungi and physico-chemical qualities of source and stored water samples in the study areas
Water samples were collected from four Local Governments (LGs) in each State based on economic status i.e. High (HESA) and Low (LESA) economic status areas. Samples collected from study area were analyzed for physicochemical constituents: Temperature (T), pH, Total Dissolved Solids (TDS), Total Hardness (TH), Biological Oxygen Demand (BOD), Magnesium ion (Mg2+) and Calcium ion (Ca2+), microbiological parameters (Total Coliform Counts (TC), Faecal Coliform Counts (FC), Fungal Counts (Fung C), Heterotrophic Plate Counts (HPC) and antifungal effectiveness of selected disinfectants on the water samples. Based on Clinical Laboratory Standard Institute (CLSI) and Neo-sensitab Standard, antifungal profiling of isolated fungal species was done using conventional antifungal drugs such as Voriconazole, Fluconazole and Nystatin.
Physicochemical studies showed that the mean values of pH (5.31-7.56), T (15.00-28.80 oC), BOD (0.50-4.20 mg/L), TH (7.56-97.46 mg/L) in all the three States fell within the standards stipulated by International and National governing bodies on potable water quality, except values of turbidity (5.27-43.49 NTU) and TH (116.26-273.33 mg/L) for some LESA which exceeded these standards. For general microbial evaluation of samples, mean counts obtained from each parameter showed that samples were grossly contaminated with mean microbial counts such as HPC (44.20-196.10), TC (1.80-156.80) and Fung C (34.40-167.60) exceeding standard stipulated by these governing bodies except Faecal (0.00-0.80) and Total coliform (0.00-0.50) counts of some HESA and LESA LGs with acceptable counts. Comparing different points (Stored and Source) water at significant difference of P<0.05, mean values of some physico-chemical parameters of most stored samples significantly exceeded that of sources. The mean counts obtained from microbial comparison of different points (Stored and Source) of collection showed that most of the Stored water possess microbial counts exceeding their Sources with very high significance level at P<0.05 as observed in all parameters carried out on Osun State samples, HPC (P=0.03) of Lagos State samples, Enterococcus (P=0.00) and Fungal (P=0.00) counts of Oyo State samples. The mycological assessment of samples show that class Deuteromycotina mainly Aspergillus species were the dominant organism followed by class Zygomycotina (Rhizopus stolonifer, Mucor spp.), while yeast-like organisms were with the least percentage. For disinfectant’s potency test, Dettol (Chloroxylenol) was most effective against fungal infested water samples while Water-care (Sodium hypochlorite) had the least antifungal activity. Antibiogram results showed that most isolates from class Deuteromycotina were susceptible to Voriconazole and Nystatin. Of the class Ascomycotina, the yeast-like organisms were susceptible to all the selected antifungal agents except Candida krusei that was resistant to Fluconazole, while isolates from class Zygomycotina were resistant to all the antifungal agents except Rhizoctonia specie that was susceptible to Nystatin.
The study concluded that the presence of some fungal species known to be immunotoxic in some of the household water might pose risk to consumers.
Description
xvii,147p
Keywords
Consumers, Physico-chemical, Microbial, Household water, Immunotoxic
Citation
Akinola,S.A.(2015). Physico-chemical and microbial quality assessment of stored and source household waters from Osun, Oyo and Lagos State. Obafemi Awolowo University