Physicochemical Properties of Water Samples in the Volta Region of Ghana: Implications for Public Health

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INTRODUCTION
The UN General Assembly Resolution 64/292 of 2010 posits that "the right to safe and clean drinking water and sanitation is a human right essential for the full enjoyment of life and all human rights" (United Nations, 2010).However, water sources in many developing countries, including Ghana, are often contaminated and do not get treated properly for domestic consumption.
The World Health Organization (WHO) estimates that 785 million people worldwide lack access to basic drinking water services, and 2 billion people use a drinking water source contaminated with faeces (WHO, 2019).In Ghana, despite significant progress in recent years, only 16% of the population have access to safely managed drinking water services (United Nations, 2022).
The physicochemical properties of water can significantly impact its quality and suitability for human consumption.These properties include pH, total suspended solids (TSS), total dissolved solids (TDS), turbidity, and the presence of various chemical contaminants such as ammonia, nitrate, phosphate, sulphate, fluoride, and heavy metals.Elevated levels of these parameters pose serious health risks and contribute to the deterioration of water quality.For instance, high levels of ammonia in drinking water can cause irritation to the eyes, nose, and throat, and can be particularly harmful to infants, leading to a condition known as methemoglobinemia or "blue baby syndrome" (Mukherjee et al., 2015).Similarly, excessive fluoride intake from drinking water can lead to dental and skeletal fluorosis, a condition characterized by the mottling of teeth and the weakening of bones (Ganta et al., 20115;Kumar & Sharma, 2011).
Despite the importance of monitoring and maintaining the physicochemical quality of water sources, there is limited data available on the specific characteristics of water in many regions of Ghana.This lack of information hinders the development and implementation of effective water treatment and management strategies, potentially exposing the population to contaminated water and associated health risks.A previous study has examined groundwater quality in some districts of the eastern region of Ghana (Fianko et al., 2010).It found that anthropogenic activities were having a significant impact on groundwater quality.Specifically, high concentrations of chloride and total dissolved solids were found in wells in high residential areas, while the highest levels of sodium, calcium, sulphate, and nitrate were found in agricultural and high-density residential areas.They also reported that about 50% of boreholes sampled had elevated levels of nitrate-nitrogen, which was attributed to agricultural runoff (Fianko et al., 2010).In a more recent study, Anornu et al., (2017) used isotopic and hydrochemical techniques to trace sources of groundwater nitrate contamination in the Upper East Region of Ghana.Their findings revealed that nitrate concentrations varied widely, with many samples exceeding baseline values.The main source of nitrate was identified as manure from both human and animal waste.Interestingly, they also found a relationship between higher nitrate levels and younger groundwater.The study highlighted potential health risks from nitrate contamination, particularly for children.These insights from previous research demonstrate that water quality issues, particularly related to anthropogenic contamination and elevated nitrate levels, have been identified in different parts of Ghana.This context provides a clear rationale for further study of physicochemical properties of water sources, particularly in other underserved regions of Ghana, such as the Volta Region.(Anornu et al., 2017;Fianko et al., 2010;Gyau-Boakye & Dapaah-Siakwan, 1999), but there is a need for more comprehensive and up-to-date assessments, particularly in underserved regions like the Volta Region.
The aim of this study was to assess the physicochemical properties of water samples collected from various sources in the Volta Region of Ghana and evaluate how they align if they meet the with World Health Organization (WHO) guidelines and to inform public health interventions and water quality management efforts in the region.

MATERIALS AND METHODS Study Design, Study Area, Sample Distribution And Collection:
A cross-sectional study was used in carrying out this study.One hundred and four (104) water samples were collected aseptically from chosen sites in Ho and its' surroundings (Fig. 1) from September 2021 to September 2022 in the following proportions; 34 direct tap water (32.69%),27 stored tap water (25.96%), 17 well water (16.35%),19 borehole water (18.27%), 5 stream water (4.81), and 2 samples of rain water (1.92).Samples taken between January and April constituted the dry season samples while those taken from May to the early part of November constituted the wet season samples.750mLs of water samples was collected from various sources, including wells, taps, boreholes, streams, and rainwater, using sterile containers.For well water, a sterile bottle was securely tied with a thread and lowered into the well without touching the walls, filled underwater, and raised back up.Tap water was sampled directly after running the tap for 2 minutes to clear stagnant water.Stored tap water was collected by agitating the container, carefully filling the bottle underwater, and sealing it before removal.Water was sampled directly from borehole after running it for 2 minutes to clear stagnant water.Stream water was collected by submerging the bottle upstream and filling it underwater.Rainwater was collected directly into a sterile, wide-mouthed bottle placed on a surface protected from runoff.All samples were sealed, labelled, and transported on ice to maintain a cool temperature until laboratory analysis.All samples were collected in duplicate.The physicochemical parameters of water samples were investigated at the Water and Sanitation Laboratory of the University of Cape Coast, Ghana.

Analysis of Sample:
Analysis of the water samples was done in accordance with the procedures suggested in the standard analytical procedure manual (Table 1) (APHA, 2012).The parameters, methodology adopted and equipment used have been listed in Table 1.
Figure 2 shows a flow chart of the methodology employed in this study.

Quality Assurance of Physicochemical Analysis:
To ensure the accuracy and reliability of the results, all measurements were performed in triplicate (Duru et al., 2019), and the average value of each set of results was used for the analysis.Prior to the study, all instruments were calibrated using standard solutions of known concentrations (APHA, 2012).For each ion under investigation, a calibration curve was constructed by analysing a series of standard solutions with known concentrations.These calibration curves were then employed to determine the concentrations of the analyte in the water samples.The value for each analyte was obtained by calculating the average of three replicate measurements.To account for any potential background interference or contamination, blank samples were prepared and subjected to the same analytical procedures as the actual samples.

Data Analysis:
The data was compiled in Microsoft Excel and analysed using IBM SPSS Statistics 26.Due to the non-normal distribution of the dataset, descriptive statistics for quantitative variables were reported using median and interquartile range.The descriptive statistics for the categorical and the quantitative variables were reported.Statistical significance was set at P < 0.05.Statistical methods such as the Kruskal-Wallis test was used to analyse differences in physicochemical properties across various water sources and between seasons.Correlation analysis was performed to examine relationships between different physicochemical parameters.Graphical displays such as bar graphs were used where appropriate to describe data.

RESULTS
The analysis of the physicochemical properties of the water samples revealed several significant findings (Table 2).The median ammonia and phosphate levels exceeded the WHO recommendations, with values of 46.2381 mg/L (interquartile range: 18.3889-101.6825mg/L) and 12.2437 mg/L (interquartile range: 1.4673-24.5775mg/L), respectively.These values are significantly higher than the WHO permissible levels of 1.5 mg/L for ammonia and 0.3 mg/L for phosphate (WHO, 2008(WHO, , 2011)).The pH values of the water samples ranged from 3.85 to 8.76, with a median pH of 6.91 (interquartile range: 6.77-7.09).While most samples fell within the WHO acceptable range of 6.5 to 8.5 (Table 1), the presence of acidic water in some sources is a concern.Most water samples (52.9%) fell within the moderately hard category, with a significant proportion (21.2%) classified as very hard (p< 0.001) (Table 3).Fluoride concentrations on the other hand were above the WHO acceptable limit of 1.5 mg/L in 38.46% of the samples tested (Table 4).The correlation analysis (Table 5) revealed strong positive associations between ammonia and phosphate levels (r=0.712,p<0.01), suggesting a common source or related underlying process contributing to the presence of these nutrients in the water samples.The Kruskal-Wallis test was used to analyse the differences in physicochemical properties across various water sources by comparing the medians for boreholes, direct tap water, stored tap water, rainwater, streams, and wells.Ammonia levels differed significantly (p=0.003), with the highest median in stream water (130.37mg/L)and the lowest in rainwater (32.06 mg/L).Phosphate levels also varied significantly (p=0.004),being lower for boreholes (1.52 mg/L) and rainwater (8.83 mg/L) compared to stream water (30.45 mg/L).Nitrate exhibited a significant difference (p=0.012), with the highest median in stream water (1.53 mg/L) compared to rainwater (0.65 mg/L).Calcium hardness differed markedly (p=0.014), with stream samples having the highest median (100.38 mg/L) as against the lowest in rainwater (14.81 mg/L).Parameters like alkalinity, pH, and fluoride did not show statistically significant differences in their medians across the water sources.The physicochemical properties of 104 samples were analysed with 53 and 51 samples collected during the dry and rainy seasons respectively.The results of this study, obtained using the Kruskal-Wallis test, indicate that the average concentrations of ammonia and phosphate were significantly higher during the dry season compared to the rainy season (Table 7).

DISCUSSION
The elevated levels of ammonia, phosphate, and fluoride in some water sources, as well as the high proportion of moderately hard to very hard water samples, highlight the need for effective water treatment and management strategies.The presence of ammonia and phosphate at concentrations exceeding WHO guidelines is a significant concern, as these nutrients can promote the growth of harmful algae and bacteria in water sources (Sharma et al., 2017).Algal blooms can produce toxins that pose risks to human health and aquatic life, while also causing taste and odour problems in drinking water (Backer, 2002;Paerl & Otten, 2013).Phosphate, in particular, is a limiting nutrient in many aquatic systems, and its excessive input can lead to eutrophication and the depletion of dissolved oxygen, with detrimental effects on water quality and ecosystem health (Smith & Schindler, 2009).
While this study focused on physicochemical parameters, the elevated levels of certain contaminants may have unique implications for public health in the Volta Region.The high ammonia concentrations observed far exceed typical environmental levels and could potentially lead to the formation of toxic chloramines if the water undergoes chlorination treatment (Li et al., 2017).Chronic exposure to chloramines has been associated with increased risk of bladder cancer and respiratory issues (Wang et al., 2019).Additionally, the synergistic effects of high ammonia and phosphate levels may create favourable conditions for harmful algal blooms, which can produce cyanotoxins.Recent research has linked cyanotoxin exposure to neurodegenerative diseases like amyotrophic lateral sclerosis (ALS) and Parkinson's disease (Sini et al., 2021).Given the region's reliance on surface water sources, this presents an alarming public health risk that warrants further investigation.
The strong positive correlation between ammonia and phosphate levels in the water samples (Table 5) suggests a common source or related underlying process contributing to their presence.Agricultural runoff, sewage discharge, and industrial effluents are known to be major sources of these nutrients in water bodies (Bhardwaj et al., 2018;Chen et al., 2020).The high levels of ammonia and phosphate in the water samples could be indicative of inadequate wastewater treatment, poor agricultural practices, or unregulated industrial activities in the region.Addressing these sources of pollution through improved waste management, agricultural best practices, and stricter regulations on industrial discharges is crucial for protecting water quality and public health (Ivar do Sul & Costa, 2014;Sasakova et al., 2018).
The presence of acidic water in some sources, as indicated by low pH values, is another area of concern.Acidic water can lead to the corrosion of pipes and the leaching of heavy metals, such as lead and copper, into the water supply (Edzwald, 2011).Exposure to these metals can have serious health consequences, particularly for children, who are more vulnerable to the neurotoxic effects of lead (Edwards, 2014;Wani et al., 2015).Regular monitoring of pH levels and the implementation of appropriate treatment methods, such as pH adjustment and corrosion control, are essential for maintaining the safety and quality of drinking water (Schock & Lytle, 2011).
The high proportion of water samples classified as moderately hard to very hard (Table 2) emphasizes the need for consumer awareness and appropriate water treatment methods.While hard water is not directly harmful to human health, it can cause aesthetic and practical issues, such as taste and odour problems, scaling in pipes and appliances, and reduced soap and detergent efficiency (Dietrich, 2006;Sengupta, 2013).Water softening techniques, such as ion exchange or reverse osmosis, can be employed to mitigate the effects of water hardness and improve the usability of water for various purposes (Djuikom et al., 2011;Wang et al., 2019).
The elevated fluoride concentrations in a substantial proportion of the water samples (Table 3) highlight the importance of regular monitoring and management of fluoride levels in drinking water sources.While fluoride at optimal levels (0.5-1.0 mg/L) can help prevent dental caries, excessive exposure can lead to dental and skeletal fluorosis, a condition characterized by the mottling of teeth and the weakening of bones (Kumar & Sharma, 2011;WHO, 2017).In areas with high natural fluoride occurrence, appropriate defluoridation technologies, such as adsorption, precipitation, or membrane processes, should be implemented to ensure safe drinking water supply (Ali et al., 2016;Ayoob & Gupta, 2006).The elevated fluoride levels found in water samples present a unique challenge in the Volta Region.While dental fluorosis is a well-known consequence of excess fluoride intake, recent studies have highlighted more subtle neurological effects.A meta-analysis by Duan et al., (2018) found that chronic exposure to high fluoride levels was associated with lower IQ scores in children, with effects observed at concentrations similar to those found in this study.Furthermore, emerging research suggests that fluoride may act as an endocrine disruptor, potentially affecting thyroid function and reproductive health (Waugh et al., 2016).
The seasonal variations observed in the physicochemical properties of the water samples (Table 6), with higher median values for ammonia and phosphate during the dry season, suggest that water sources may be more vulnerable to contamination during this period.Reduced water flow, increased evaporation, and concentrated pollutant loads from various sources, such as agricultural runoff, sewage discharge, and industrial effluents, can contribute to the deterioration of water quality during the dry season (Cobbina et al., 2012;Gyamfi et al., 2019).These findings emphasize the need for regular monitoring and adaptive management strategies to ensure the safety and reliability of drinking water supplies throughout the year (Giri & Qiu, 2016).The seasonal variations in water quality observed in this study may have important implications for waterborne disease transmission in the region.The higher levels of ammonia and phosphate during the dry season could create favourable conditions for bacterial growth, including potential pathogens.Research has shown that changes in water chemistry can influence the virulence and antibiotic resistance of waterborne bacteria (Colwell et al., 2003).This suggests that the seasonal fluctuations in water quality may not only affect the abundance of pathogens but also their potential to cause disease.
The higher average levels of total hardness, ammonia, phosphates, and fluoride in tap water samples compared to other sources indicate that the water distribution system may play a role in the elevated levels of these parameters.Aging infrastructure, inadequate treatment processes, and intermittent water supply can contribute to the deterioration of water quality in distribution networks (Lee & Schwab, 2005;Wright et al., 2004).Biofilm formation, leakage, and crosscontamination within distribution systems can also introduce contaminants and compromise the safety of drinking water (Liu et al., 2018).Regular monitoring, maintenance, and upgrades of water distribution infrastructure are essential for ensuring the delivery of safe and high-quality drinking water to consumers (Hrudey et al., 2006).

CONCLUSION
The elevated levels of ammonia, phosphate, and fluoride in some water sources, as well as the high proportion of moderately hard to very hard water samples, highlight the need for effective water treatment and management strategies.The seasonal variations and differences among water sources emphasizes the importance of regular monitoring and targeted interventions to ensure access to safe drinking water.The strong correlations observed between certain physicochemical parameters, such as ammonia and phosphate, suggest the need for a holistic approach to water quality management that considers the interconnectedness of various contaminants and their sources.
The results also highlight the importance of regular monitoring and maintenance of water distribution systems to ensure the delivery of safe and high-quality drinking water to consumers.Water service providers and public health authorities should prioritize the upgrading of aging infrastructure, the optimization of treatment processes, and the implementation of effective disinfection strategies to maintain water quality throughout the distribution network.Based on the seasonal dynamics of water quality observed in this study, there is a need for adaptive management strategies and public awareness campaigns to minimize the risks associated with contaminated water sources, particularly during the dry season.
Overall, this study contributes to a better understanding of the physicochemical properties of water sources in the Volta Region of Ghana and their potential impacts on public health.The findings serve as a basis for future research and inform evidence-based decision-making in water quality management and public health interventions.By addressing the identified water quality issues and promoting access to safe drinking water, we can make significant strides towards improving public health and achieving the United Nations' Sustainable Development Goal 6, which aims to ensure availability and sustainable management of water and sanitation for all.

Recommendations:
Based on the findings of this study, the following recommendations are proposed: support in the laboratory.Their dedication and hard work in assisting in the performance of these extensive experimental procedures and analyses were instrumental to the success of this research.We sincerely thank Dr. Jones Gyamfi and Dr. Gameli Deku for generously providing technical expertise and guidance throughout this research.Your wisdom and insights greatly facilitated the progression of the study.

Table 1 :
Methods of analysis of samples.

Table 2 :
Analysis of physicochemical properties of water samples.
mg/L= milligrams per litre; pH= power of Hydrogen; p value is significant at p≤ 0.05.P value was generated using the Wilcoxon Signed Rank Test.No specific health-based guideline value from WHO for Magnesium.

Table 3 :
Analysis of the categories of water hardness.
p-value = Median of moderate vrs hard vrs very hard

Table 4 :
Analysis of fluoride concentration.
p-value = Acceptable vrs Above acceptable

Table 5 :
Correlation between the various physicochemical properties of water samples.
Table 6 below provides further details.

Table 6 :
Analysis of physicochemical properties across the various water sources.

Table 7 :
Seasonal variation in physicochemical parameters of water samples.
• Implement regular water quality monitoring and prioritize interventions to reduce contamination, particularly for tap water sources.Strengthen monitoring programs, improve wastewater treatment, agricultural practices, and industrial effluent control, and invest in upgrading and maintaining water distribution infrastructure.• Promote the use of appropriate household water treatment methods like ion exchange or reverse osmosis to address water hardness and fluoride issues.Develop public awareness campaigns and educational programs to inform consumers about the benefits and availability of treatment options, and to minimize risks from contaminated water sources, especially during the dry season.• Foster collaboration and an integrated approach to sustainably monitor and manage water quality for public health.This study forms part of a larger study that received ethical clearance from the Committee on Human Research, Publications and Ethics of Kwame Nkrumah University of Science and Technology (KNUST)-Ghana, with reference number (CHRPE/AP/371/20).Conflict of interests: The authors declare no conflicts of interest.Authors Contributions: Emmanuel U. Osisiogu, Kwabena O. Duedu, Bhavana Singh and Patrick K. Feglo developed the concept and directed the research.Emmanuel U. Osisiogu and Samuel N. Boateng carried out sample collection, laboratory and data analysis as well as manuscript draft preparation.All authors have read, reviewed, and approved the content of the last version of this manuscript.Funding: This study received no external funding.