Concentration and Potential Human Health Hazards of Heavy Metals in Periwinkle (Tympanotonus fuscatus) Purchased from Major Markets in Calabar, Nigeria

Abstract

Background. As water flows through habitats associated with estuaries, such as mud flats, salt marshes, sea grass and mangrove forests, pollutants such as heavy metals are filtered. The fine sediment dominant in intertidal and subtidal estuarine systems is an important sink for these contaminants. Periwinkle, which inhabit estuarine ecosystems, are known to bioaccumulate large quantities of contaminants.