Levels of Lead, Cadmium and Chromium in Oreochromis Niloticus in Lagos State Lagoon

Abstract

Lead (Pb), Cadmium (Cd) and Chromium (Cr) levels in Oreochromis niloticus, aquatic plants, water and sawdust were collected and analyzed for Lead, Cadmium and Chromium using atomic absorption spectroscopy. Results obtained showed that sawdust had the highest Lead and Chromium contents of 32.0 + 0.99 μg/g and 54.7 + 55.65μg/g respectively. Aquatic plant had the highest concentration of Cadmium 37.0 μg/g + 3.96μg/g. The differences between the levels of Lead and Cadmium in sawdust and fish were statistically significant while there was no significant difference in the level of Chromium between sawdust and fish. The difference in Cadmium and Chromium between plant and fish were also statistically significant. All statistical analysis was carried out at 95% confidence limit (P < 0.05) using student t-test. From these results, it was deduced that sawmilling, log transportation and domestic waste disposal into the lagoon may have been responsible for these high metal levels.