Effect of depuration on heavy metal concentrations in periwinkle (<i>Tympanatonus fuscastus</i>) from a polluted creek in Rivers State, Nigeria

Abstract

The efficiency of depuration in the removal of heavy metals in Periwinkle (Tympanatonus fuscastus) was evaluated in this study. Periwinkle in depuration tanks were taken at intervals of 24, 48, 72 and 96 hours of depuration and analyzed for these heavy metals: Lead (Pb), Zinc (Zn), Chromium (Cr) and Cadmium (Cd). Results from the analyses shows that time, method and season has significant effect on heavy metals. At different location, there was significant difference at different time interval of depuration for both seasons. The control for all the locations had the highest count for depuration at both seasons. The concentration of Pb, Cr, Cd and Zn for depurated periwinkle at 24-96 hours was significantly different (P<0.05) from control for both rainy and dry season. Notably, at 96hours of depuration, these metals were reduced. The depuration of these contaminants on the shellfish was faster during rainy season than dry seasons brought about satisfactory results. This study depuration method at the different time intervals is suggested.

Keywords: Heavy metals, purification, processing, pollutants, Tympanatonus fuscastus