Distribution of trace elements in water, fish and earthworm from warri river in delta state of Nigeria

Water, fish and earthworm samples collected from Enerhen and Otokutu areas along the Warri River were analytically treated and analysed for trace metals using atomic absorption spectrophotometer (AAS) of Model Perkin. Elmer 311 A. A total of twelve sample points were mapped out in both Enerhen and Otokutu areas. This study was carried out for a period of six months (July – December). The results obtained showed that all the metals analysed were detected and varied from one point to another. Lowest trace metal values were obtained in water samples whereas highest mean metal values were recorded in fish samples. This is an indication that vertebrates accumulate more metals than invertebrates. Chromium, lead and iron concentrations in water exceeded the WHO limits for drinking water indicating that the water is not fit for drinking. Also, Cadmium, Copper and Lead mean values in the fish and earthworm in this study far exceeded the recommended Daily Intakes Set by Food Standards Australia New Zealand. A critical look at the results further revealed that earthworm accumulates copper levels more than the fish. This is because earthworm is a bioindicator for the availability of Copper in ecosystems. Highest mean concentrations of iron were obtained in water, fish and earthworm in that order. These elevated iron levels are attributed to activities of the Delta Steel Company located around Warri.