Effect of Storage and Exposure to Sunlight on the Quality of Sachet Water Sold in Ibadan Metropolis

Ikpeazu Joy Chinenye

doi:10.11648/j.sjph.20170504.17

Abstract

Inadequate pipe borne water supply has led to rapid proliferation of sachet water companies in Nigeria. Recently, another dimension added to public health concerns on water quality is the storage and handling of sachet water by distributors and vendors. This study assessed the effect of storage and exposure to sunlight on the quality of sachet water in Ibadan, Nigeria. An experimental design was adopted. Two hundred sachets of water from ten brands were collected upon production from various factories. Water samples were divided into two groups: storage indoor (room temperature) and storage with exposure to sunlight for four weeks. Physicochemical and bacteriological analyses were carried out on the sachet water samples at baseline and after three days and weeks one to four of storage. The data obtained were analysed using SPSS (20.0). The bacteria isolated were E. coli, S. aureus, K. pneumonia and P.vulgaris. Total bacterial counts decreased in the order: 0 to 1.5x104cfu/100 mL (day 3) > 0 to 9.5x 102 cfu/100 mL (day 7) upon exposure to sunlight, however, there was continuous increase of bacteria count from day seven. Bacteria counts of water stored indoor increased throughout the study period. E. coli was present in all water samples by day 21. There was a significant difference in nitrite concentration between the two storage conditions across study period. This study revealed that storage duration and exposure conditions affect the quality of sachet water for drinking. Quality improvement of sachet water through exposure to sunlight was most effective on third day of exposure, while the maximum time of effectiveness was one week, beyond which the quality deteriorates fast irrespective of the storage condition. Hence, prolonged water storage beyond one week before drinking is discouraged.

Highlights

Good quality water is odourless, colourless, tasteless, and free from faecal pollution [1]
Physicochemical and bacteriological examination of samples showed a variable level (p < 0.05) of pH, turbidity, chloride, nitrite and bacteria count with their highest values in week four which were all within permissible limits except nitrite, turbidity and bacteria counts
The high nitrite level in sachet water may predispose the consumers to methemoglobinaemia which has been linked to increased concentration of nitrite in drinking water especially in bottlefed infants when such contaminated water is used for their formula [14, 15]

Summary

Introduction

Good quality water is odourless, colourless, tasteless, and free from faecal pollution [1]. In Ibadan, Nigeria, the Water Corporation of Oyo State supplies 107 million litres of water per day for a population of 3.6 million through the Eleyele and Asejire dams this quantity is adequate for only 20% of the population [2] The outcome of this inadequacy is that most people in the city resort to water from other sources such as boreholes, wells, and water from several vendors without knowing the source. According to [4], the inadequacy of pipe borne water supply in Nigeria is a growing problem; as a result people resort to buying water from vendors, and sachet or bottled water became a major source of drinking water. The exposed group was stored outdoor where sunlight could reach it while the unexposed group was stored indoor at room temperature for a period of four weeks, during which physicochemical and bacteriological analyses were carried out on samples from the two groups at intervals

Laboratory Analyses

Data Analysis

Results and Discussion

Conclusion and Recommendation