Rivers are the major sources of water being used in cities and its environs. This water may either be treated or untreated. River banks could be very busy, varied activities ranging from farming to industrial activities and other domestic household activities are conducted. The present study aimed at investigating the potential sources of selected heavy metal contaminants in River Mukurumudzi, Kwale County. Water and sediments were sampled in four points along the river impacted by mining, human settlements and agricultural activities for three different seasons. The samples were analyzed for Iron, Lead, Cadmium, Copper and Arsenic using an AAS. Sediment quality was also analysed by the calculation of CF and I-geo values. Interpretation of results was conducted using Minitab statistical software and Excel spreadsheets. The range of metals in water during the dry season was Fe (0.19-0.32) mg/l, Pb, Cu, Cd and As were below the detection limits. The range of metals in water during the short rain was Fe (0.12-1.25) mg/l and BDL for all other analysed metals. The range of metals in water during the long rain season was Fe (0.07-1.82) mg/l, Cu (0.08-0.11) mg/l and BDL for all the other analysed metals. The range of metals in sediments during dry season was Fe (0.13-1.44) ppm, Pb (0.08-0.54) ppm, and BDL for all other analysed metals. The range of metals in sediments during short rain season was Fe (0.23-1.73) ppm, Pb (0.12-0.27) ppm, and BDL for all other analysed metals. The range of metals in sediments during the long rain season was Fe (0.25-2.75) ppm, Pb (0.09-0.34) ppm, Cu (0.10-0.14) ppm, and BDL for all other analysed metals. The CF values for sediments were all <1 which indicated low contamination. The I-geo values of metals in sediments were all <1 suggesting the sediments are practically unpolluted. The concentrations of metals in water were all within the NEMA, KEBS and WHO limits thereby indicating non-contamination. River Mukurumdzi water and sediments are not contaminated by heavy metals. However, there is need for the land-based activities to be assessed since elevation of metal concentration was observed during the rainy seasons because of run-off from these sources.
KEY WORDS: Heavy metals, AAS, BDL, Sediments and Water contamination, I-geo and CF
Table of Contents
1. INTRODUCTION
1.1 Background Information.
1.2 Statement of the problem
1.3 Objectives
1.3.1 Research Questions.
1.3.2 Research Hypothesis
1.4 Justification
1.5 Scope of study and limitation.
1.5.1 Scope of Study
1.5.2 Limitation of the study
1.6 Assumptions of the study.
2. LITERATURE REVIEW
2.1 Introduction
2.2 Rivers and Pollution from Land Based Activities.
2.3 Heavy metal and pollution
2.4 Sources of Heavy metal pollution
2.5 Heavy metals and water pollution
2.6 Heavy metals in Sediments
2.7 Heavy Metal pollution in Kenya.
2.8 Kwale County and River Mukurumudzi
3. MATERIALS AND METHODS
3.1 Introduction
3.2 Description of study area
3.3 Methodology
3.3.1 Sampling procedure
3.3.2 Data collection approach
3.3.3 Data Collection Techniques
3.3.4 Validity and reliability of research instruments
3.3.5 Data Analysis and presentation
3.3.6 Validation of results
4. RESULTS AND DISCUSSION
4.1 Heavy metals in water
4.2 Heavy metals in sediments
4.3 Comparisons of heavy metals.
4.3.1 Correlations between heavy metals.
4.3.2 ANOVA Comparisons of heavy metal concentrations between sites
4.4 Water Contamination
4.5 Sediments Contamination.
4.5.1 Geo-accumulation Index results
4.5.2 Contamination Factor (CF) results
5. CONCLUSIONS AND RECOMMENDATIONS
5.1 Conclusions
5.2 Recommendations
Research Objectives and Topics
The research investigates potential heavy metal contamination in River Mukurumudzi, Kwale County, specifically focusing on the impact of local land-based activities such as mining and commercial agriculture. The central research question assesses the concentration levels of selected heavy metals (Pb, Fe, Cu, Cd, As) in water and sediments across different seasons to determine if anthropogenic activities contribute to environmental pollution.
- Impact of industrial mining and agricultural runoff on river water quality.
- Comparative analysis of heavy metal concentrations in water vs. riverbed sediments.
- Seasonal fluctuations in contamination levels based on rainfall patterns.
- Assessment of environmental health using standard contamination indices (I-geo and CF).
- Baseline data generation for future environmental monitoring in the region.
Excerpt from the Book
1.1 Background Information.
Water is essential for life. It is utilized for domestic purposes, agricultural production, industrial activities, and among many other uses. Water is a basic amenity to humanity on the planet earth. Water is managed poorly in many parts of the world despite it being important for life (Fakayode, 2005). Water is a good solvent; and due to this characteristic, water will always dissolve and contain mineral constituents and other substances that it leaches out on contact. Naturally, pure water is hard to find. The contamination of water in a particular area is always directly related to the degree of contamination of its environment (Peng et al., 2005). While trickling down rainwater collects impurities from the atmosphere. Consequently, impurities from surface run-off, sewage discharges and industrial effluents are collected by rivers and streams in their course of flow (Skeat, 1969). Rivers and streams are important sources and channels for the movement and transportation of anthropogenic metals to the ocean (Everaats and Niewenhuize, 1995; Nicolas et al., 2006; Adamo et al., 2005).Water pollution from anthropogenic activities has been documented in many parts of the world (Adenkule, 2009; Lars,2003). Many rivers, lakes, wetlands, ground waters and oceans suffer a great loss of degradation from various human activities. These activities have effects on water quality, changing both its physiochemical and biological parameters making it unsuitable not only for domestic use, but also for other purposes.
Summary of Chapters
CHAPTER ONE: Provides the context of water importance, defines the problem of potential heavy metal contamination in River Mukurumudzi, and outlines the research objectives and hypotheses.
CHAPTER TWO: Reviews literature on global and local water pollution, the chemistry and sources of heavy metals, and the specific environmental context of Kwale County.
CHAPTER THREE: Details the field study area, the sampling procedures for water and sediments, the analytical techniques using Atomic Absorption Spectrophotometry, and the validation methods.
CHAPTER FOUR: Presents the analytical results of heavy metal concentrations, performs comparative analyses across seasons and sites, and interprets the data through I-geo and CF indices.
CHAPTER FIVE: Concludes that the river is not currently highly contaminated by heavy metals while recommending regular monitoring of iron levels near mining and plantation areas.
Keywords
Heavy metals, AAS, BDL, Sediments, Water contamination, I-geo, CF, Mining, Agriculture, River Mukurumudzi, Environmental monitoring, Kenya, Anthropogenic impact, Water quality, Seasonal variation.
Frequently Asked Questions
What is the core focus of this research?
The study aims to determine the potential levels of heavy metal contamination in the water and sediments of River Mukurumudzi, Kwale County, arising from local land-based activities.
Which heavy metals were analyzed?
The study specifically measured concentrations of Lead (Pb), Iron (Fe), Copper (Cu), Cadmium (Cd), and Arsenic (As).
What is the primary objective of the study?
The main objective is to assess the level of contamination from anthropogenic sources, specifically mining operations and large-scale farming, and compare these levels with natural occurrence values.
Which scientific method was employed for metal detection?
The researchers utilized Flame Atomic Absorption Spectrophotometry (AAS) to analyze the concentration of the selected metals in water and sediment samples.
What does the main body of the work cover?
The main body covers the literature review, the description of the study area, data collection techniques, laboratory analysis, and a comprehensive discussion of the results including correlation analyses and contamination indices.
What are the primary keywords characterizing this work?
Key terms include heavy metals, AAS, I-geo, Contamination Factor (CF), sediments, water quality, anthropogenic impact, and seasonal variation.
Did the study find significant contamination in River Mukurumudzi?
Overall, the study concludes that the river is not heavily contaminated by heavy metals, as most concentrations were within acceptable regulatory limits, though enrichment of certain metals was observed during rainy seasons.
How did the researchers justify the study?
The study was justified by the reliance of local communities on the river for domestic needs, the potential impact of mineral-rich geology in Kwale County, and the lack of previous baseline data for this specific river basin.
What was the role of sediment analysis in the findings?
Sediment analysis served as a critical indicator for long-term contamination, as sediments act as a sink for heavy metals transported through the river ecosystem.
What are the final recommendations of the author?
The author recommends regular monitoring of iron levels near mining sites and further studies on the environmental impact of damming activities on the river.
- Quote paper
- Edwin Mwashinga (Author), 2018, Determination of Selected Heavy Metals in River Mukurumudzi to Establish Potential Contamination from Land Based Activities and Sources, Munich, GRIN Verlag, https://www.grin.com/document/424220
