Levels of Heavy metals in Juvenile Fish obtained in Nike River

Introduction:

Aquatic environments are essential for human survival as they are the sources of food and water for human consumption. The Nike River, located in Enugu State, Nigeria, is one of such water bodies that support human livelihoods. The river serves as a source of irrigation for crops and a source of fish for human consumption. However, the river is subject to pollution from industrial effluents, domestic waste, and agricultural activities, leading to the accumulation of heavy metals and nutrients in the river. The contamination of aquatic ecosystems by heavy metals has become a major environmental concern worldwide, and has received increasing attention due to their potential toxic effects on aquatic organisms and human health. Heavy metals are toxic, persistent and bioaccumulative, meaning that they can remain in the environment for long periods of time, accumulate in the tissues of living organisms, and pose a serious threat to human health and aquatic life. Cadmium, chromium, nickel, lead, and copper are among the most common heavy metals found in aquatic ecosystems, and have been shown to have harmful effects on aquatic organisms and their ecosystems. The Nike River, located in Enugu, Nigeria, is an important source of water for the people living in the surrounding communities, and it is also used for fishing and other economic activities. However, due to the rapid industrialization and urbanization in the area, the Nike River has become increasingly polluted by heavy metals, as well as other contaminants such as phosphate and nitrates. As a result, the aquatic life in the river, including fish, may be affected, and the ultimate consumers of the fish, humans, may also be at risk of exposure to these contaminants. In this research, we aim to determine the levels of cadmium, chromium, nickel, lead, and copper in the liver, tissues, gills, and blood of juvenile tilapia and aeroplane fish from the Nike River, and to evaluate the potential health risks to humans who consume these fish. Additionally, we will investigate the effects of phosphate and nitrates on aquatic life in the Nike River. Previous research has shown that heavy metals can have harmful effects on aquatic life, including reduced growth, reproduction, and survival rates, as well as behavioral and physiological changes. For example, studies on the effects of cadmium on fish have shown that it can cause liver and kidney damage, impaired growth, and reduced reproductive capacity. Chromium has also been shown to have toxic effects on fish, including damage to gills, liver, and kidneys, as well as behavioral changes. Similarly, nickel has been linked to reduced growth and reproductive capacity in fish, and lead has been shown to cause damage to the nervous system and other organs. Heavy metals and nutrients are major pollutants in aquatic environments, and they pose a significant threat to aquatic life and human health. Heavy metals such as cadmium, chromium, nickel, lead, and copper are toxic to aquatic organisms, and their accumulation in aquatic organisms can lead to bioaccumulation and biomagnification in the food chain (Adeyemo et al., 2020). Nutrients such as phosphates and nitrates, on the other hand, are essential for aquatic plant growth, but their excess can lead to eutrophication, leading to the depletion of dissolved oxygen and the death of aquatic organisms (McLusky et al., 2015). Fish, being an essential source of protein for humans, are vulnerable to the accumulation of heavy metals and nutrients in aquatic environments. Tilapia and aeroplane fish are two species of fish commonly found in the Nike River. The juveniles of these fish species are more vulnerable to heavy metal accumulation than the adult fish (Adeyemo et al., 2020). The accumulation of heavy metals in fish can lead to various health effects in humans, such as cancer, kidney damage, and nervous system damage (Yang et al., 2020). Several studies have been conducted on the Nike River's water quality, and it has been found to be polluted with heavy metals and nutrients (Ikegwu et al., 2019; Ugochukwu et al., 2021). However, there is a dearth of information on the levels of heavy metals and nutrients in tilapia and aeroplane fish, the effect of these pollutants on fish health, and their ultimate effect on human health. Therefore, this study aims to determine the levels of cadmium, chromium, nickel, lead, and copper in the liver, tissues, gills, and blood of juvenile tilapia and aeroplane fish from the Nike River and their potential effects on human health. Additionally, this study aims to investigate the effects of phosphates and nitrates on aquatic life in the Nike River.: Furthermore, studies have demonstrated that the consumption of contaminated fish can lead to health problems in humans, including kidney damage, cancer, and neurological disorders. Therefore, it is crucial to determine the levels of heavy metals in fish from the Nike River and to assess the potential health risks to human consumers. Moreover, phosphate and nitrates are two of the most common pollutants found in aquatic ecosystems, and have been linked to eutrophication and hypoxia, leading to a decline in water quality and loss of aquatic biodiversity. Previous studies have shown that the excessive use of fertilizers and other agricultural practices can lead to high levels of phosphate and nitrates in water bodies, which can then lead to the growth of harmful algal blooms and oxygen depletion, negatively affecting aquatic life. The findings from this study will provide essential information for policymakers and stakeholders to develop strategies to manage and mitigate the pollution of the Nike River. This study will also provide vital information for consumers of fish from the Nike River on the potential health risks associated with the consumption of fish contaminated with heavy metals and nutrients. Citations: Farkas, A., et al. (2003). “Heavy metal concentrations in fish tissues from the Danube River.” Environment International 28(7): 713-719. Iwegbue, C. M. A., et al. 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