Investigation on the Storage Stability of Packaged Water Commonly Produced in Ilorin Metropolis, Kwara State, Nigeria

This study investigated the effects of storage conditions on the physicochemical parameter, microbial 11 loads and health risks assessment of randomly 30 selected sachet and bottle water brands (A, B and C) 12 in Ilorin Metropolis. Random sampling procedures were used to collect samples from three different 13 brands and subjected to three different storage conditions; immediately (initial), mild sunlight and intense 14 sunlight condition. The heavy metals (Cr, Pb and Fe) investigated in this study were above the 15 permissible limits (WHO, SON). The presence of TBC, TCC, FCC and TFC in all the water samples 16 analyzed showed no effective quality control system. Incremental lifetime cancer risk (ILCR) assessment 17 revealed a carcinogenic health risk to the populace drinking this water. It can be deduced from this study 18 that water stored under sunlight for a long period of time is not good for human consumption and 19 therefore adequate monitoring by the appropriate agencies are emphasized. 20 21 22


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Water is an essential liquid for human day to day activities which contain two atoms of hydrogen 27 and one atom of oxygen. It is a basic need for human existence that is require to maintain personal  Previous researchers have estimated that over 1.8 million people in most of the developing 35 countries lack adequate good water supply as a result of increase in population (Oyelude and 36 business in most developing countries which is very lucrative due to the rate at which consumers 38 buy this packaged water (sachet and bottle). Sachet and bottle water can come from a variety of 39 sources, including groundwater from a well, water from a protected spring, or water from a public 40 water supply. However, there is a great risk associated with water produced in an unsafe and 41 unhygienic environment (Tortora et al. 2002) and this often resulted into several health challenge Similarly, several researchers reported that the main source of problem associated with production 46 of sachet and bottle water is the way of handling during the production process, storage for several 47 weeks and contamination which can also be attributed to the use of pipe for a longer period (initial) after purchased from the factories. Group 2 samples were stored in a container and exposed 64 to sunlight for six weeks (mild condition). While Group 3 were stored and exposed directly (intense 65 condition) to the sunlight without a container for six weeks.

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The pH was measured using a pH meter Ino Lab Tech 7310 digital multimeter which give direct 69 value of pH and it was calibrated with buffer solutions (pH 4 and 7). Thermometer was used to 70 measure the temperature of the water samples in-situ. Electrical conductivity (EC) and total 71 dissolved solid (TDS) were determined by HANNA Digital multimeter and it was calibrated with 72 potassium chloride solution. Alkalinity, hardness, chloride and calcium contents were determined 73 titrimetrically. The concentration of magnesium contents was determined by subtracting the 74 concentrations of calcium from total hardness. Sulphate contents were determined 75 turbidimetrically and Nitrate contents were determined by Brucine method (APHA 2017).   The association between the concentration of the toxic metals (Fe, Pb, and Cr) and their apparent 91 risk to human health is generally appraised by the human health risk assessment models established

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The mean temperature value ranged from 28.6 0 C -30.6 0 C for all brands water samples analyzed

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Turbidity values in all the brand of water samples analyzed (Bottle and Sachet) were found to be 169 less than 5 NTU for all the water samples exposed to different conditions of storage (initial, mild 170 and intense). This is similar to the results obtained in the previous work (Anake et al. 2013 observed from these results that there is an increase in conductivity values of water brands exposed 183 to intense sunlight for six weeks.

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Alkalinity values ranged from 2.00 mg/L -8.00 mg/L for all the water brand samples investigated.

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It was observed that there is a variation in concentration of the water samples exposed to various increases gradually when exposed to various conditions as compared to that of the initial analysis.

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The presence of Lead in high concentration can damage nervous connection (especially in young 263 children), cause blood and brain disorder, it is also a cumulative poison and a possible human   Since the result reveals values of ILCR that are 100% higher than the recommended limit, the 299 general populace are in danger of carcinogenic health effect. However, it is noteworthy that the 300 reported carcinogenic and non-carcinogenic risk values in this study may be undervalued because value was recorded in bottle water. This is indicating that most of the bottle water analyzed were 324 below the limit while sachet water analyzed were found to be above limits.

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Faecal coliform values ranged from 0.5 Cfu/100ml -2.5 Cfu/100ml and 0.5 Cfu/100ml -1.0 327 Cfu/100ml in both bottle and sachet water respectively. It was observed that samples of water increase in FCC of the water samples exposed to mild and intense temperature. Most of the water 330 samples investigated were above the threshold limit sets as indicated in the table 1 above.

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Total fungi count (TFC) was not detected in all the brand of bottle water samples stored under 333 different conditions (initial, the mild sunlight and intense condition). TFC found in all the sachet 334 water samples ranged from 0 Cfu/100ml -2.0 Cfu/100ml which are higher than the permissible 335 limit by WHO and SON. TFC done on all the brands of water analyzed at zero day (initial) has 0 336 Cfu/100ml for all the brand water samples but those water samples stored at mild sunlight exposure 337 has higher TFC (0.6 Cfu/100ml -2.0 Cfu/100ml) than those stored under intense sunlight exposure 338 (0.5 Cfu/100ml -1.1 Cfu/100ml This is because microbes will not survive at higher temperature.