Project Material on HEAVY METAL CONCENTRATIONS IN AFRICAN RIVER PRAWN (MACROBRACHIUM VOLLENHOVENII) OF ETHIOPE RIVER

HEAVY METAL CONCENTRATIONS IN AFRICAN RIVER PRAWN (Macrobrachium vollenhovenii) OF ETHIOPE RIVER

 

ABSTRACT

The concentrations of four heavy metals (cadmium, chromium, nickel and vanadium) in the African river prawn (Macrobrachium vollenhovenii) sampled in three months (April, May and June) at three locations along the Ethiope River bank in Delta State, were investigated by means of an atomic absorption spectrophotometer. A total of 135 samples of M. vollenhovenii were collected from the three locations: Station A (Ogberikoko), Station B (Ogorode) and Station C (Ugbeyiyi) along the river. Results showed that the total mean concentrations of metals in M. vollenhovenii were as follows: Cd (0.1182mg/kg), Cr (0.0792mg/kg), Ni (0.0764mg/kg) and V (0.3323mg/kg). The corresponding total mean values in the water were: Cd (0.0591mg/l), Cr (0.0567mg/l), Ni (0.0329mg/l) and V (0.0389mg/l) respectively. Significant differences (p<0.05) were recorded between the concentration of each metal in M. vollenhovenii during the different months of sampling. However, the concentration of Ni was not significantly different (p>0.05) in the month of April compared to May. No significant differences (p>0.05) were recorded between the concentration of each metal in the water during the months of sampling except Ni that was significantly different (p<0.05) in the month of April when compared to the month of June. Metal concentrations in prawns were lower than the Food and Agriculture Organisation, (FAO), the World Health Organisation (WHO) and Federal Ministry of Environment (FMENV) recommended limits in fish and fishery products. However, the concentrations of Cd and Cr in water exceeded the recommended limits for portable drinking water by WHO. 

 

CHAPTER ONE

INTRODUCTION

BACKGROUND OF THE STUDY

Heavy metal pollution in aquatic ecosystems is a growing environmental concern worldwide. Heavy metals, including lead (Pb), cadmium (Cd), mercury (Hg), and chromium (Cr), are toxic substances that can have detrimental effects on both aquatic organisms and human health. These metals enter water bodies through various anthropogenic activities such as industrial discharges, agricultural runoff, and improper waste disposal practices. Once released into aquatic environments, heavy metals can accumulate in the tissues of aquatic organisms, potentially causing harmful effects on their physiology and ecology.

One important species that serves as an indicator of heavy metal contamination in freshwater ecosystems is the African river prawn (Macrobrachium vollenhovenii). African river prawns are widely distributed in African rivers and estuaries, including the Ethiope River in Ethiopia. They play a crucial role in the ecological balance of these aquatic systems and are also an important source of income and nutrition for local communities who rely on fishing activities.

Understanding the levels of heavy metal contamination in African river prawns is essential for assessing the overall health of the aquatic ecosystem and evaluating the potential risks associated with the consumption of contaminated seafood. Previous studies have reported the presence of heavy metals in various aquatic organisms, highlighting the need for continuous monitoring and assessment of heavy metal concentrations in freshwater species.

In the case of the Ethiope River, limited research has been conducted on heavy metal contamination in African river prawns. Therefore, this study aims to investigate the concentrations of Pb, Cd, Hg, and Cr in the muscle tissue of African river prawn specimens collected from different locations along the Ethiope River. By determining the heavy metal levels in these prawns, we can gain insights into the extent of heavy metal pollution in the river system and evaluate the potential risks to both the prawns themselves and human consumers.

The findings of this study will contribute to the existing knowledge on heavy metal contamination in freshwater ecosystems and provide valuable information for environmental management and conservation efforts. Furthermore, this research will serve as a basis for future studies on the identification of pollution sources, the assessment of ecological impacts, and the development of strategies to mitigate heavy metal pollution in the Ethiope River and other similar aquatic systems.

 

STATEMENT OF THE PROBLEM

Heavy metal contamination in aquatic ecosystems poses significant threats to both the environment and human health. The Ethiope River in Ethiopia is an important freshwater system that supports a diverse range of aquatic organisms, including the African river prawn (Macrobrachium vollenhovenii). However, limited research has been conducted on the levels of heavy metal concentrations in this species within the Ethiope River.

The presence of heavy metals such as lead (Pb), cadmium (Cd), mercury (Hg), and chromium (Cr) in the muscle tissue of African river prawns can have severe implications for both the prawns themselves and human consumers who rely on them as a source of food. These heavy metals can accumulate in the prawns' tissues, posing a risk to their health and survival. Additionally, if these contaminated prawns are consumed by humans, they can lead to adverse health effects, including heavy metal poisoning.

Therefore, the problem at hand is the lack of comprehensive information regarding the levels of heavy metal concentrations in African river prawns within the Ethiope River. Understanding the extent of heavy metal contamination in these prawns is crucial for assessing the overall health of the aquatic ecosystem and evaluating the potential risks associated with the consumption of contaminated seafood. Addressing this knowledge gap is essential for implementing effective environmental management strategies and safeguarding both the ecological integrity of the Ethiope River and the well-being of local communities reliant on this valuable aquatic resource.