ANALYSIS AND HEALTH RISK ASSESSMENT OF PER-AND POLYFLUOROALKYL SUBSTANCE (PFAS) IN THE WATER AND SEDIMENTS OF RIVERS NIGER AND BENUE IN LOKOJA, KOGI STATE

CHAPTER ONE: 5

INTRODUCTION.. 5

1.1 Background of the Study. 5

1.2 Statement of the Problem.. 7

1.3 Research Questions. 10

1.4 Objectives of the Study. 10

1.5 Significance of the Study. 11

1.6 Scope and Limitation of the Study. 13

1.7 Definition of Terms. 14

CHAPTER TWO: 16

LITERATURE REVIEW... 16

2.1 Conceptual Framework. 16

2.1.1 Definition of PFAS. 16

2.1.2 Sources and Pathways of PFAS. 18

2.1.3 Environmental Behavior of PFAS. 20

2.2 Theoretical Framework. 23

2.2.1 Risk Assessment Theory. 23

2.2.2 Environmental Toxicology Theory. 24

2.3 Empirical Review.. 26

2.3.1 Studies on PFAS in Water. 26

2.3.2 Studies on PFAS in Sediments. 28

2.3.3 Health Risks Associated with PFAS. 30

2.4 Summary of Literature Review.. 31

CHAPTER THREE: 33

RESEARCH METHODOLOGY.. 33

3.1 Research Design. 33

3.2 Study Area. 33

3.3 Population and Sampling Technique. 34

3.4 Data Collection Methods. 34

3.4.1 Water Sampling. 34

3.4.2 Sediment Sampling. 34

3.4.3 Laboratory Analysis. 35

3.5 Data Analysis Techniques. 35

3.6 Ethical Considerations. 35

3.7 Validity and Reliability of the Study. 36

CHAPTER FOUR: 37

RESULTS AND DISCUSSION.. 37

4.1 Introduction. 37

4.2 Descriptive Analysis. 37

4.2.1 Water Quality Parameters. 37

4.2.2 Sediment Quality Parameters. 38

4.3 PFAS Concentrations. 40

4.3.1 PFAS in Water. 40

4.3.2 PFAS in Sediments. 42

4.5 Discussion of Findings. 44

4.5.1 Comparison with Standards. 44

4.5.2 Implications for Public Health. 44

4.5.3 Implications for Environmental Management 45

CHAPTER FIVE: 46

CONCLUSION AND RECOMMENDATIONS. 46

5.1 Conclusion. 46

5.2 Recommendations. 46

5.2.1 Policy Recommendations. 46

5.2.2 Recommendations for Future Research. 47

5.3 Contribution to Knowledge. 47

5.4 Limitations of the Study. 47

References. 49

CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

Per- and polyfluoroalkyl substances (PFAS) are a large group of human-made chemicals that have been used in various industrial applications and consumer products since the 1940s. These substances are widely recognized for their resistance to heat, water, and oil, leading to their use in products such as non-stick cookware, water-repellent clothing, stain-resistant fabrics, and firefighting foams (Giesy & Kannan, 2019). Recent studies have highlighted the persistence, bioaccumulation, and potential toxicity of PFAS, raising concerns about their impact on environmental and human health (Ritter, 2021).

The environmental persistence of PFAS is attributed to the strength of the carbon-fluorine bonds, making them resistant to degradation. Consequently, PFAS have been detected globally in various environmental media, including water, soil, and air, as well as in wildlife and humans (Buck et al., 2020). This widespread distribution has prompted researchers to investigate the pathways through which PFAS enter and accumulate in the environment and biota (Wang et al., 2022).

Rivers Niger and Benue, the two largest rivers in Nigeria, are vital water bodies that support diverse ecosystems and provide water for domestic, agricultural, and industrial uses. These rivers converge in Lokoja, Kogi State, creating a significant confluence that impacts the surrounding environment and communities (Onojake et al., 2022). Given the importance of these rivers, understanding the levels and sources of contaminants, such as PFAS, is crucial for environmental monitoring and public health protection.

Recent research has shown that PFAS contamination in rivers can result from various sources, including industrial discharges, urban runoff, and wastewater effluents. Studies in other regions have reported elevated PFAS concentrations in river water and sediments, emphasizing the need for localized assessments to inform risk management strategies (Zhao et al., 2020). In Nigeria, limited data exists on the presence and levels of PFAS in major water bodies, underscoring the need for comprehensive studies in this area (Adetokunbo et al., 2023).

The potential health risks associated with PFAS exposure have become a significant concern for public health authorities. PFAS have been linked to various adverse health effects, including cancer, liver damage, thyroid disease, and developmental issues in children (ATSDR, 2021). The mechanisms through which PFAS exert their toxic effects are still being studied, but it is believed that their ability to bind to proteins and interfere with hormonal and metabolic processes plays a key role (Gallo et al., 2021).

In Lokoja, the confluence of Rivers Niger and Benue creates a unique environmental setting where PFAS from upstream activities may accumulate and pose risks to local populations. This study aims to assess the levels of PFAS in the water and sediments of these rivers, providing a basis for evaluating the potential health risks to the residents of Lokoja (Ezeh et al., 2023). Understanding the spatial distribution and concentration of PFAS is essential for developing effective remediation and regulatory strategies.

Furthermore, the findings from this study will contribute to the global database on PFAS contamination, helping to identify patterns and trends that can inform international efforts to manage and mitigate PFAS pollution (Scheringer et al., 2021). By comparing the results with established safety guidelines and standards, the study will provide insights into the adequacy of current regulations and the need for potential adjustments (USEPA, 2022).

In summary, the persistence, bioaccumulation, and potential health risks of PFAS necessitate thorough investigation and monitoring, particularly in regions with significant water bodies like Lokoja. This study seeks to fill the knowledge gap on PFAS levels in Rivers Niger and Benue, contributing to a better understanding of the environmental and health implications of these substances (Adeniyi et al., 2023). Through comprehensive analysis and risk assessment, the research aims to support the development of informed policies and interventions to protect both the environment and public health.

1.2 Statement of the Problem

Per- and polyfluoroalkyl substances (PFAS) are recognized for their environmental persistence and potential adverse health effects. Despite global concerns, there is a significant knowledge gap regarding the presence and impact of PFAS in Nigeria, particularly in the water and sediments of major rivers such as Niger and Benue. The lack of comprehensive studies in this region hinders effective environmental management and policy formulation aimed at mitigating the risks associated with PFAS contamination (Adetokunbo et al., 2023).

PFAS contamination in water bodies poses a direct threat to aquatic ecosystems and human health. In regions where rivers serve as primary sources of drinking water, the presence of PFAS can lead to bioaccumulation in fish and other aquatic organisms, subsequently affecting the health of communities that rely on these resources for their diet (Wang et al., 2022). The detection of PFAS in Rivers Niger and Benue could indicate significant exposure risks for local populations in Lokoja, Kogi State, necessitating urgent attention and remediation efforts.

The industrial and urban development along Rivers Niger and Benue contributes to the discharge of PFAS into these water bodies. Activities such as manufacturing, use of firefighting foams, and waste disposal can introduce these persistent chemicals into the environment (Zhao et al., 2020). In Lokoja, where these rivers converge, the potential for compounded contamination is high, posing a unique challenge for environmental monitoring and public health interventions (Onojake et al., 2022).

Health risk assessments of PFAS exposure have linked these chemicals to various diseases, including cancer, liver damage, and endocrine disruption. The lack of local data on PFAS levels in Rivers Niger and Benue limits the ability to assess and mitigate these health risks effectively (ATSDR, 2021). Understanding the concentration and distribution of PFAS in these rivers is critical for developing appropriate health risk assessments and protective measures for the residents of Lokoja (Ezeh et al., 2023).

Existing studies on PFAS contamination predominantly focus on developed countries, with limited research conducted in developing regions like Nigeria. This disparity in research efforts creates a significant gap in the global understanding of PFAS distribution and impact, particularly in areas with different industrial and environmental contexts (Buck et al., 2020). Addressing this gap through localized studies is essential for a comprehensive global assessment of PFAS pollution and its risks (Scheringer et al., 2021).

The current regulatory framework in Nigeria does not adequately address PFAS contamination, largely due to the lack of specific guidelines and standards for these substances. This regulatory gap hinders effective environmental monitoring and risk management, leaving local populations vulnerable to the potential health effects of PFAS exposure (Adetokunbo et al., 2023). Developing robust regulatory measures requires detailed data on PFAS levels and sources, which this study aims to provide.

The convergence of Rivers Niger and Benue in Lokoja creates a dynamic and complex hydrological environment that may influence the distribution and behavior of PFAS. Understanding these dynamics is crucial for accurate environmental assessments and effective management strategies (Onojake et al., 2022). The study of PFAS in this confluence area will provide valuable insights into the transport and fate of these substances in large river systems.

Public awareness and understanding of PFAS risks in Nigeria are limited, further complicating efforts to address contamination issues. Educating local communities about the sources, pathways, and health effects of PFAS is essential for fostering community engagement in environmental protection initiatives (Ezeh et al., 2023). This study will contribute to raising awareness and informing the public about the potential risks associated with PFAS in their water sources.

There is an urgent need for comprehensive environmental assessments of PFAS in Nigeria to support evidence-based policy and decision-making. The findings from this study will provide critical data for stakeholders, including government agencies, environmental organizations, and public health officials, to develop and implement effective strategies for managing PFAS contamination (Gallo et al., 2021). This research will serve as a foundation for future studies and policy developments aimed at safeguarding environmental and public health.

In summary, the persistent and potentially hazardous nature of PFAS, coupled with the lack of local data and regulatory measures in Nigeria, underscores the necessity of this study. By analyzing PFAS levels in the water and sediments of Rivers Niger and Benue in Lokoja, this research will address a critical gap in environmental monitoring and risk assessment, contributing to the development of informed policies and protective measures (Adeniyi et al., 2023).

1.3 Research Questions

1)    What are the concentrations of per- and polyfluoroalkyl substances (PFAS) in the water and sediments of Rivers Niger and Benue in Lokoja, Kogi State?

2)    What are the potential sources of PFAS contamination in the Rivers Niger and Benue?

3)    What are the potential health risks associated with PFAS exposure for the local population in Lokoja, considering both water and sediment contamination?

4)    How do the levels of PFAS in Rivers Niger and Benue compare with established safety guidelines and standards for environmental and human health?

      1.4 Objectives of the Study

1. To determine the concentrations of per- and polyfluoroalkyl substances (PFAS) in the water and sediments of Rivers Niger and Benue in Lokoja, Kogi State.
2. To identify the potential sources of PFAS contamination in the Rivers Niger and Benue.
3. To assess the potential health risks associated with PFAS exposure for the local population in Lokoja, considering both water and sediment contamination.
4. To compare the levels of PFAS in Rivers Niger and Benue with established safety guidelines and standards for environmental and human health.

The study on the analysis and health risk assessment of per- and polyfluoroalkyl substances (PFAS) in the water and sediments of Rivers Niger and Benue in Lokoja, Kogi State, holds significant importance for several reasons. Firstly, it addresses a critical knowledge gap regarding the presence and levels of PFAS in major Nigerian water bodies. This is essential as PFAS have been recognized globally for their persistence, bioaccumulation, and potential health risks (Ezeh et al., 2023). By providing localized data, the study contributes to a better understanding of environmental contamination in Nigeria, which has been underrepresented in global PFAS research (Adetokunbo et al., 2023).

Secondly, the study’s findings will be crucial for environmental monitoring and regulatory agencies in Nigeria. The data on PFAS concentrations in Rivers Niger and Benue will help in formulating and implementing effective policies and regulations to control and mitigate PFAS pollution. Currently, Nigeria lacks specific guidelines and standards for PFAS, and this study will provide the necessary evidence to support the development of such regulations (Adeniyi et al., 2023).

Moreover, the study will benefit public health by assessing the potential health risks associated with PFAS exposure for the local population in Lokoja. Understanding the health implications of PFAS contamination is vital for protecting communities that rely on these rivers for drinking water, fishing, and other daily activities (ATSDR, 2021). The risk assessment component of this research will inform public health interventions and guide efforts to minimize exposure to these harmful substances.

The research also has significant implications for the scientific community. It will add to the growing body of knowledge on PFAS, particularly in developing countries where research is still limited. The study’s methodology and findings can serve as a reference for future research on PFAS contamination in other regions, promoting a more comprehensive understanding of the global distribution and impact of these substances (Buck et al., 2020).

Furthermore, the study will raise awareness among local communities about the presence and risks of PFAS in their environment. Increased awareness can lead to more community engagement in environmental protection efforts and demand for better regulation and management of contaminants (Gallo et al., 2021). Public education campaigns based on the study’s findings can empower residents to advocate for cleaner water and safer environmental practices.

The economic implications of this study are also noteworthy. By identifying and addressing PFAS contamination, the research can help prevent the potential economic costs associated with health care for diseases linked to PFAS exposure and the degradation of natural resources (Scheringer et al., 2021). Effective management of PFAS pollution can protect fisheries, agriculture, and tourism, which are vital sectors for the local economy.

In addition, the study will support international efforts to manage PFAS pollution. By contributing data from Nigeria, the research enhances the global understanding of PFAS distribution and risks, which is essential for developing international guidelines and collaborative strategies to address this widespread issue (Zhao et al., 2020). The study’s findings will be valuable for global databases and comparative analyses that inform worldwide environmental policies.

Lastly, the research findings will be instrumental in guiding future environmental research and interventions in Nigeria. They will highlight the need for ongoing monitoring and studies on emerging contaminants, fostering a proactive approach to environmental health and safety (Wang et al., 2022). The study sets a precedent for comprehensive environmental assessments, encouraging further research and action to protect the environment and public health in Nigeria and beyond.

1.6 Scope and Limitation of the Study

The scope of this study encompasses the analysis and health risk assessment of per- and polyfluoroalkyl substances (PFAS) in the water and sediments of Rivers Niger and Benue in Lokoja, Kogi State. The research will focus on measuring the concentrations of various PFAS compounds in these rivers, identifying potential sources of contamination, assessing the associated health risks for the local population, and comparing the detected levels with established safety guidelines and standards. The study aims to provide comprehensive data that can inform policy decisions and environmental management practices regarding PFAS pollution.

However, this study has certain limitations. One of the primary limitations is the geographical focus on Lokoja, which may not capture the full extent of PFAS contamination in other regions along Rivers Niger and Benue. The findings may, therefore, not be fully generalizable to other areas. Additionally, the study is constrained by the availability and sensitivity of analytical techniques for detecting low concentrations of PFAS in environmental samples. Advanced and sensitive equipment is required to accurately measure PFAS levels, which may pose logistical and financial challenges.

Another limitation is the potential variability in PFAS concentrations due to seasonal changes and differing hydrological conditions. Sampling during a specific period may not reflect the year-round PFAS levels in the rivers. Furthermore, while the study will identify potential sources of PFAS contamination, it may not be able to establish definitive causal relationships due to the complex nature of environmental pollution. Despite these limitations, the study aims to provide valuable insights into PFAS contamination and its health risks, laying the groundwork for future research and policy development in Nigeria.

1.7 Definition of Terms

Per- and Polyfluoroalkyl Substances (PFAS): A group of synthetic chemicals characterized by their strong carbon-fluorine bonds, known for their persistence in the environment and potential adverse health effects.

Water and Sediments: Refers to the liquid and solid components of rivers, specifically Rivers Niger and Benue, which are the primary focus of this study.

Health Risk Assessment: The process of estimating the potential adverse health effects of exposure to hazardous substances, such as PFAS, based on exposure levels and toxicological data.

Environmental Management: Refers to the practices and policies aimed at monitoring, controlling, and mitigating environmental pollution and its impacts.

Safety Guidelines and Standards: Established thresholds and criteria set by regulatory bodies or organizations to protect human health and the environment from harmful substances.

Lokoja, Kogi State: A specific geographical area in Nigeria where Rivers Niger and Benue converge, chosen as the study location for assessing PFAS contamination.

Concentration: The amount of a particular substance (e.g., PFAS) present in a given volume or mass of water or sediment, usually expressed in parts per million (ppm) or parts per billion (ppb).

Sources of Contamination: Refers to the various human activities, such as industrial processes, wastewater discharges, and chemical use, which introduce PFAS into the environment.

Analytical Techniques: Methods and instruments used to detect and quantify PFAS compounds in environmental samples, such as water and sediment samples collected from Rivers Niger and Benue.

Policy Development: The process of formulating rules, regulations, and guidelines based on research findings and scientific evidence to address environmental and public health concerns related to PFAS contamination.