Comparative Evaluation of Natural and Synthetic Coagulants for Water Treatment: A Case Study of Moringa Oleifera and Alum

CHAPTER ONE

INTRODUCTION

1.1 Background to the Study

Freshwater systems provide essential resources for drinking, agriculture, sanitation and industrial activities. However, these water bodies now face increasing contamination from microplastics. Microplastics are plastic particles smaller than 5 millimeters that originate from the breakdown of larger plastics or from direct release of manufactured microbeads used in cosmetics and cleaning products (Cole et al., 2011). Their presence in rivers, lakes and streams has become a global environmental concern because they persist for long periods and accumulate in aquatic environments (Rochman et al., 2013).

Microplastic pollution has increased rapidly due to growing plastic production, poor waste management and indiscriminate disposal. Because plastics degrade slowly, they fragment into smaller particles rather than fully decompose. Consequently, microplastics appear in sediments, surface waters and even treated drinking water (Mason et al., 2018). Studies show that they also absorb harmful chemicals such as pesticides, hydrocarbons and heavy metals, making them transport vehicles for toxic substances (Teuten et al., 2009).

Recent research indicates that humans may ingest microplastics through drinking water, fish consumption or inhalation of airborne particles (Wright & Kelly, 2017). Although the full health implications remain under investigation, existing evidence suggests potential risks, including inflammation, oxidative stress and chemical toxicity (Smith et al., 2018). Therefore, assessing microplastic contamination in freshwater sources has become essential for understanding environmental risk and protecting public health.

This study evaluates microplastic presence in selected freshwater sources and examines possible implications for human health based on established scientific evidence.

1.2 Statement of the Problem

Microplastics have been detected in freshwater systems worldwide, yet many regions lack detailed assessments of contamination levels. In several developing countries, waste management systems remain inadequate. As a result, large amounts of plastic waste enter rivers and streams during rainfall or through direct dumping (Akindele et al., 2020). Without reliable data, communities and policymakers cannot determine the severity of microplastic pollution or develop appropriate control strategies.

Although scientists increasingly highlight the potential health risks of microplastic exposure, many uncertainties remain. Concentration levels vary widely across water bodies, and the toxicity depends on polymer type, particle size and associated chemicals. Because freshwater sources supply drinking water to millions of people, understanding the extent of contamination is crucial. This study addresses these gaps by assessing microplastics in selected freshwater samples and discussing associated human health concerns.

1.3 Aim of the Study

The aim of this study is to assess microplastic contamination in freshwater sources and evaluate its potential implications for human health.

1.4 Objectives of the Study

The specific objectives are:

1. To collect and analyze freshwater samples for microplastic particles.

2. To identify microplastic types, sizes and morphological characteristics.

3. To determine the concentration of microplastics in selected water bodies.

4. To compare observed contamination levels with published global findings.

5. To examine possible health implications associated with microplastic exposure.

1.5 Research Questions

1. What types and concentrations of microplastics occur in selected freshwater sources

2. How do particle size and morphology vary across sampling sites

3. How do contamination levels compare with global reports

4. What potential health risks are associated with microplastic ingestion

5. What measures can help reduce microplastic pollution

1.6 Research Hypotheses

H1: Microplastics are present in selected freshwater sources at concentrations that may pose potential health risks.
H0: Microplastics are not present in selected freshwater sources at concentrations that may pose potential health risks.

1.7 Significance of the Study

This study is important for several reasons. First, it provides scientific evidence about the presence and concentration of microplastics in freshwater sources. Such information supports environmental monitoring and guides policy decisions. Second, the study highlights potential human health implications, which can help health authorities design better public awareness programs. Third, the research contributes to global data on microplastic contamination by adding findings from regions where limited data currently exist.

Moreover, understanding contamination levels helps improve waste management strategies. Identifying the sources and types of microplastics can guide interventions that reduce environmental pollution. Finally, the study benefits researchers, environmental agencies and policymakers seeking evidence-based strategies to address rising plastic pollution.

1.8 Scope of the Study

The study focuses on microplastic contamination in selected freshwater bodies. It includes field sampling, laboratory analysis and morphological characterization of microplastic particles. Chemical toxicity testing, marine systems and deep groundwater sources fall outside the scope.

1.9 Limitations of the Study

Several factors may limit this research. Microplastic concentration may vary seasonally, and sampling conducted at a single period may not represent annual fluctuations (Mason et al., 2018). Laboratory instruments may also limit the detection of very small particles below the microplastic size range. Despite these limitations, the study uses validated methods to ensure accurate and relevant results.

1.10 Organization of the Study

The research is presented in five chapters. Chapter One introduces the study and outlines its objectives, significance and limitations.  Review of literature on microplastic pollution, freshwater contamination and health implications is presented in Chapter Two. Chapter Three describes the sampling procedures and analytical methods. Chapter Four presents and discusses the results. While  Chapter Five concludes the study and provides recommendations for environmental protection and future research.

 References 

Akindele, E. O., Ehlers, S. M., & Koop, J. H. (2020). First evidence of microplastics in freshwater environments in Nigeria. Environmental Science and Pollution Research, 27(7), 2908–2915.

Cole, M., Lindeque, P., Halsband, C., & Galloway, T. S. (2011). Microplastics as contaminants in the marine environment: A review. Marine Pollution Bulletin, 62(12), 2588–2597.

Mason, S. A., Welch, V. G., & Neratko, J. (2018). Synthetic polymer contamination in bottled water. Frontiers in Chemistry, 6, 407.

Rochman, C. M., Browne, M. A., Halpern, B. S., Hentschel, B. T., Hoh, E., Karapanagioti, H. K., Rios-Mendoza, L. M., Takada, H., Teh, S., & Thompson, R. C. (2013). Policy: Classify plastic waste as hazardous. Nature, 494(7436), 169–171.

Smith, M., Love, D. C., Rochman, C. M., & Neff, R. A. (2018). Microplastics in seafood and the implications for human health. Current Environmental Health Reports, 5(3), 375–386.

Teuten, E. L., Saquing, J. M., Knappe, D. R., Barlaz, M. A., Jonsson, S., Björn, A., Rowland, S. J., Thompson, R. C., … & Yamashita, R. (2009). Transport and release of chemicals from plastics to the environment and to wildlife. Philosophical Transactions of the Royal Society B, 364(1526), 2027–2045.

Wright, S. L., & Kelly, F. J. (2017). Plastic and human health: A micro issue? Environmental Science & Technology, 51(12), 6634–6647.