BIOACUMULATION OF HEAVY METALS IN FRESH WATER CLAN

BIOACUMULATION OF HEAVY METALS IN FRESH WATER CLAN (Egeria radiata)

CHAPITRE ONE

1.0 General Introduction

1.1 Historical Background

Pollution of the coastal waters of Nigeria’s Niger delta region has recently been greatly altered due to the high degree of environmental degradation and aquatic disturbances caused by petroleum exploration activities in oil-bearing states. Petroleum hydrocarbons from oil spills and human-caused activities are typically incorporated into sediments, where they can persist for years, gradually releasing toxic substances such as heavy metals into the immediate and distant environment (O’Clar et al., 1996; Moles and Norcoss, 1998; Zabby and Babatunda, 2015). The distribution of heavy metals in aquatic habitats. Divergent dynamics are present based on elements such as source, flow rates, particle flux rate, sediment properties, and the ecology of the animals under study. Most reports in the Niger delta concur that heavy metal concentrations in surface water samples are modest (Davies et al., 2004). Chindah et al., 2006) sediment, on the other hand, is thought to be a sink for heavy metals, allowing for re-suspension whenever the river is disturbed (Babatunda et al., 2013). Most researchers, however, use benthic organisms as biomonitors of both the amounts and long-term influences of heavy metals within an ecosystem to better characterize the risk presented by metals in the environment to human and ecological receptors (Phlilps and Rainbow, 1994; Horsfall et al., 1998).

Fishing is one of the main vocations of the residents of the Niger Delta region, and numerous fishery resources, such as Egeria radiate, are essential delicacies. The significance of heavy metal poisoning of aquatic ecosystems cannot be overstated, as most of them can bioaccumulate and become major along the food chain, raising consumer concerns about seafood safety (Davies et al., 2006). Selfish, particularly clams such as E. radiate and Tympanotonus species, are commonly used as a condiment in most meals consumed in the Niger delta and its environs (Gomna and Rana, 2007, Babatunde et al., 2005) and may collect metals at amounts that are harmful to human consumers.

Bivalves are commonly utilized as bioindicators of heavy metals pollution in coastal waters because they are known to accumulate metals, offering signals of environmental contamination over time. Ergeria Nwanbeze (2011) observed elevated concentrations of heavy metals in tissue of E. radiata from several creeks in Delta state Nigeria above concentrations in the environment, particularly Pb, Mn, and Cd, which were greater than FAO/WHO permissible limits of heavy metal contamination in fishes and shellfish. Similarly, Etim (1990) found significant heavy metal contamination in tissues of E. Radiata from the Calabar River in Cross River, Nigeria, which was higher than the environmental concentration, showing that the metals were bioaccumulated by the animal. Indeed, numerous studies conducted around the world have demonstrated their ability to concentrate trace elements even in areas far from anthropogenic sources, such as the anthracitic ocean (Maur et al., 1990, and Nigro 1992; Viarengo et al., 1993), with seasonal variations in concentration at various stages of their life (Bryan, 1973), and in the bay of la Rocchelle in France (Bustamante and Miramand, 2005).

A variety of anthropogenic activities in Itu bridgehead waters can have a negative impact on the water and sediment chemistry. This will have an impact on benthic organisms such as Egaria radiata. Because this creature considered a delicacy in the area, heavy metal levels in it will be analyzed to determine its acceptability for food.

1.2 Purposes and Goals

Cadmium (cd), chromium (cr), lead (pb), and iron (fe) levels were measured in the meat of E radiata from the ITU bridgehead.

To compare the heavy metal levels measured to the WHO norm.

To determine the acceptability of E. radiata for eating from the ITU bridgehead.