Biochemical Investigation of Drinking Water Sources (Boreholes) in Kano Metropolitan Area: Microbial Load, Heavy Metals, and Health Biomarkers ABSTRACT

Biochemical Investigation of Drinking Water Sources (Boreholes) in Kano Metropolitan Area: Microbial Load, Heavy Metals, and Health Biomarkers

ABSTRACT

Access to safe drinking water remains a major public health concern in urban Nigeria. Boreholes are a primary source of potable water in Kano metropolis; however, contamination from microbial and chemical sources poses health risks. This study evaluates the microbial load, heavy metal concentrations (lead, cadmium, iron, and zinc), and associated health biomarkers among residents consuming borehole water in Kano.

Water samples were collected from 50 randomly selected boreholes across Kano metropolis. Standard microbiological techniques were used to quantify bacterial and fungal counts, while atomic absorption spectrophotometry determined heavy metal concentrations. Blood samples from residents regularly consuming borehole water were analyzed for kidney and liver function biomarkers, including creatinine, urea, ALT, and AST.

Results indicated that several boreholes contained microbial counts exceeding WHO permissible limits. Lead and cadmium concentrations were elevated in a subset of boreholes, correlating with increased serum creatinine and ALT levels in residents. The study highlights potential health risks linked to long-term consumption of contaminated borehole water. Recommendations include routine water quality monitoring, proper borehole maintenance, and public awareness campaigns to mitigate exposure and protect public health in Kano metropolis.

Keywords: Borehole water, Microbial contamination, Heavy metals, Biochemical markers, Kano metropolis, Drinking water safety.

CHAPTER ONE

1.0 Introduction

Water is essential for human survival, yet access to safe drinking water remains a challenge in many Nigerian urban centers. In Kano metropolis, boreholes are a common source of potable water for households, schools, and small businesses. Despite their popularity, these water sources are vulnerable to microbial contamination and accumulation of heavy metals from environmental and anthropogenic activities.

Consuming contaminated water can lead to gastrointestinal infections, chronic kidney disease, liver dysfunction, and other health complications. Microbial contaminants include Escherichia coli, Salmonella, and fungi, which can proliferate in poorly maintained boreholes. Chemical contaminants, especially heavy metals such as lead, cadmium, iron, and zinc, may arise from geological formations, industrial effluents, or improper waste disposal.

Assessing the quality of borehole water is crucial to safeguarding public health. This study investigates microbial load, heavy metal concentrations, and associated biochemical changes in residents consuming borehole water in Kano metropolis.

1.1 Statement of the Problem

Although boreholes provide convenient access to water, many are not routinely monitored, leading to potential exposure to pathogens and toxic metals. Elevated microbial loads and heavy metals in drinking water can contribute to chronic health conditions such as liver and kidney dysfunction. In Kano metropolis, there is limited scientific data linking water contamination from boreholes to biochemical alterations in consumers, creating a knowledge gap that this study seeks to address.

1.2 Aim and Objectives of the Study

The main aim of this study is to evaluate the safety and biochemical impacts of borehole water consumption in Kano metropolis.

Specific objectives include:

1. To determine the microbial load in borehole water samples.

2. To quantify heavy metal concentrations (lead, cadmium, iron, zinc) in borehole water.

3. To assess biochemical health markers (kidney and liver function) in residents consuming borehole water.

4. To correlate water quality parameters with changes in biochemical biomarkers.

5. To recommend measures for improving borehole water safety and public health.

1.3 Research Questions

1. What is the microbial load in borehole water sources in Kano metropolis?

2. What are the levels of heavy metals in these borehole water sources?

3. How do these water contaminants influence kidney and liver function in consumers?

4. Is there a correlation between water contamination and biochemical marker alterations?

1.4 Research Hypotheses

• H₀₁: Borehole water in Kano metropolis contains microbial and heavy metal levels within WHO permissible limits.

• H₁₁: Borehole water in Kano metropolis contains microbial and heavy metal levels exceeding WHO permissible limits.

• H₀₂: Contaminated borehole water does not significantly affect kidney and liver biochemical markers in consumers.

• H₁₂: Contaminated borehole water significantly affects kidney and liver biochemical markers in consumers.

1.5 Significance of the Study

This study provides vital information on the quality of borehole water in Kano metropolis and its potential health impacts. The findings can guide public health officials, water authorities, and policymakers to implement interventions that reduce exposure to waterborne contaminants. Additionally, the research contributes to community awareness about water safety and the importance of regular water quality monitoring.

1.6 Scope of the Study

The study focuses on borehole water in Kano metropolis. Microbiological analysis, heavy metal determination, and assessment of biochemical markers in consumers were conducted. Other water sources, such as municipal pipe water or rainwater, are beyond the scope of this research.

1.7 Operational Definition of Terms

• Borehole Water: Groundwater accessed via drilled wells for domestic or commercial use.

• Microbial Load: The quantity of bacteria, fungi, and other microorganisms present in water.

• Heavy Metals: Metallic elements, such as lead, cadmium, iron, and zinc, which can be toxic at elevated concentrations.

• Biochemical Markers: Biological indicators in blood used to assess organ function, including kidney and liver enzymes.

• WHO Permissible Limits: Maximum allowable concentrations of contaminants in drinking water as recommended by the World Health Organization.

CHAPTER TWO

2.0 Literature Review

This chapter reviews studies on borehole water quality, microbial contamination, heavy metal accumulation, and associated biochemical effects in consumers.

2.1 Microbial Contamination of Borehole Water

Borehole water can harbor pathogenic microorganisms due to improper construction, lack of sanitation, and infiltration from surface water. Studies in Nigeria have shown that E. coli, Salmonella, and Shigella are common in borehole water, posing risks of diarrhea, cholera, and typhoid. Oloruntoba et al. (2020) reported that microbial contamination is a significant public health challenge in urban areas, especially in high-density settlements.

2.2 Heavy Metals in Drinking Water

Heavy metals such as lead and cadmium accumulate in water from industrial effluents, waste disposal, and corrosion of pipes. Chronic exposure can lead to nephrotoxicity, hepatotoxicity, and cardiovascular diseases. Ahmed et al. (2019) found elevated lead and cadmium levels in groundwater from northern Nigerian cities, highlighting the need for continuous monitoring.

2.3 Biochemical Biomarkers of Water Contamination

Exposure to contaminated water affects kidney and liver functions, which can be monitored using biochemical markers. Serum creatinine, urea, ALT, and AST are commonly used to evaluate organ health. Long-term ingestion of heavy metals elevates these markers, indicating organ stress or damage. Nwachukwu et al. (2018) demonstrated significant correlations between waterborne heavy metals and biochemical alterations in Nigerian urban populations.

2.4 Relationship Between Microbial and Chemical Contamination and Health

Contaminated borehole water can simultaneously expose consumers to pathogens and toxic metals, compounding health risks. Integrated monitoring of microbial load, heavy metals, and biochemical markers provides comprehensive insight into water safety and human health outcomes.

2.5 Research Gap

Most studies in Kano focus either on water quality or health outcomes separately. There is limited integrated research assessing microbial load, heavy metals, and biochemical health markers among consumers of borehole water in Kano metropolis. This study fills this gap and provides data for evidence-based interventions.

2.6 Summary of Literature Review

Borehole water in urban Nigeria faces challenges of microbial and chemical contamination. These contaminants can adversely affect human health, especially kidney and liver function. Evaluating both water quality and biochemical markers in consumers is essential to understand health risks and implement appropriate mitigation strategies.