Influence of storage containers on the physicochemical and microbiological (biofilm formation) indices of drinking water sources

ABSTRACT Effect of surfaces of earthenware pots, glass, plastic and stainless steel containers on the physicochemical and bacteriological (biofilm formation) quality of borehole and atmospheric water stored for twelve days were determined using standard analytical and bacteriological techniques. Susceptibility of the bacterial isolates to different antibiotics was also determined using standard Kirby-Bauer agar disc diffusion procedures. The physicochemical parameters determined for borehole water sample were within WHO permissible standard while rain water sample recorded slightly higher values for NO3 -, and NO2 -(10.2 mgL -1 and 0.045 mgL -1 respectively) than WHO standards of 10 mgL -1 and 0.02 mgL -1 respectively. Biofilm bacterial communities from stored borehole water consisted of nine genera including Pseudomonas, Micrococcus, Klebsiella, Bacillus, Staphylococcus, Escherichia, Proteus, Serratia, and Enterobacter. The recovery rate of the various bacterial genera were 40% in earthenware pot, 80% in plastic, 70% in stainless steel and 60% of the genera were isolated from glass container for stored borehole water. Fewer bacterial genera were isolated from stored atmospheric water and these included Pseudomonas, Bacillus, Staphylococcus, Streptococcus and Yersinia. The isolates were recovered at the rates of 40%, 80%, 60% and 40% in earthenware pot, plastic, stainless steel and glass containers respectively. While Escherichia coli, Yersinia sp and Pseudomonas aeruginosa exhibited remarkable sensitivity to Septrin (30 μg), Ampicillin (30 μg), Augmentin (30 μg) and Nalidixic acid (10 μg) as evinced by clear zones of inhibition, Enterobacter sp, Klebsiella sp and Proteus sp were moderately sensitive to some of the tested antibiotics. Amongst the gram positive bacteria, Micrococcus sp was most sensitive to the various antibiotics. Although Staphylococcus aureus showed resistance to most of the tested antibiotics, it was sensitive to Erythromycin (30 μg) and Chloramphenicol (30 μg). It could be deduced from the above results that the physicochemical and bacteriological quality of stored water are affected by both the source of the water and type of storage vessel. Although the effect of the vessels are not definitive, the levels of pH, Mg 2+ , NO2 -, NO3 -and hardness are enhanced in water stored in earthenware pots. The isolation of antibiotic resistant bacteria from stored water is of public health concern, thus, drinking water should not be held in containers for more than a day or two. Citation: Udofia GE, Ofon UA, Asamudo NU, Ndubuisi-Nnaji UU (2015). Influence of storage containers on the physicochemical and microbiological (biofilm formation) indices of drinking water sources

Prospects of nanosorption and photocatalysis in remediation of oil spills

Nanoremediation approaches have been applied to remove oil from surface and ground water as oil spills have been found to have long-term negative consequences for the ecosystem. Nanoremediation via the nanosorption mechanism of different environmental matrices in the world at large is at its formative stages despite the alarming and extensive prevalence of petroleum related environmental pollution. Over 9 million barrels of oil have been leaked in the last five decades, making that ecosystem one of the most deteriorated by oil exploration and extraction activities. The goal of this research is to assess the current status, trends, and future prospects of the nanosorption of surface and ground water in oil spill regions. High surface area of nanomaterials, wide spectrum of treatable contaminants, non-generation of intermediate or secondary products, as well as speed and extent of contaminant destruction give nanoremediation a superior comparative edge over other treatment technologies. Notably, the remediation efficiency of a cleanup is highly dependent on the type of material and treatment routes employed. It is imperative to employ a concerted and practical approach to the development of nanotechnology to combat the bedeviling oil pollution challenges faced in oil producing counties