Effects of Sunlight Exposure on the Quality Parameters of Bottled Water

Mo Akharame,Fi Okolafor,Ka Sadoh,A Ekhosuehi

doi:10.4314/jasem.v22i5.31

Abstract

This study was conducted to determine the physicochemical, heavy metal and microbiological effect of sunlight exposure on bottled water quality. Nine brands of bottled water commonly produced and sold in Benin City were exposed to sunlight for 0 day, 14 days and 28 days and evaluated for physicochemical parameters (pH, EC, TDS, alkalinity, hardness, Ca 2+ , Mg 2+ , Na + , K + , Cl - ), heavy metals levels (Pb, Cd, Zn, As) and microbial content using standard methods. Results obtained showed that 96.30% of the pH values were below the WHO (6.5-8.5), SON (6.5-8.5) and NIS (7.5) standards, a gradual decline in the values was also observed with increasing sunlight exposure. Other physicochemical parameters were within the established standards with steady increments in the values with increasing sunlight exposure, except for alkalinity which declined consistently due to increase in the acidity levels of the water samples. There was a general increase in the Zn concentration for all bottled water brands from 0 day to 28 days, except for brand C which remained the same, while Pb, Cd, As level were not detected. Interestingly, a gradual decrease of the microbial population (total coliform) of the bottled water with increasing exposure to sunlight was observed. In all, the varying exposure to sunlight did not result in statistical significant changes (P< 0.05) in the water quality.

Highlights

Water is essential for life as it plays a key role in body metabolism and properfunctioning of cells (Kleiner, 1999)
Drinking good quality water is vital for human health and development (UNICEF and WHO, 2012).A reliable supply of good drinking water is needed to promote healthy living amongst the inhabitants of any geological region (Isikwuel and Chikezie, 2014).Bottled water consumption has become very widespread and it appears to have filled the need for safe drinking water which has led to the tremendous increase in its demand
This investigation was carried out to determine the effect of sunlight exposure on the physicochemical properties, heavy metals levels and microbial content of some selected bottled water sold in Benin City and to underscore the possible health effect of drinking bottled water exposed to sunlight over a period of time

Summary

Introduction

Water is essential for life as it plays a key role in body metabolism and properfunctioning of cells (Kleiner, 1999). Studies had shown that plastics bottles (polyethylene terephthalate) are susceptible to degradation under high temperature (Bach et al, 2009), and it is a common practice for local stores to leave bottled water exposed to sunlight before being traded. This investigation was carried out to determine the effect of sunlight exposure on the physicochemical properties, heavy metals levels and microbial content of some selected bottled water sold in Benin City and to underscore the possible health effect of drinking bottled water exposed to sunlight over a period of time

Methods

Results

Conclusion