Trace Elements in Edible Rocky Shore Species: Effect of Sewage Discharges and Human Health Risk Implications

ABSTRACT

Sewage pollution is a worldwide concern and can result in increasing levels of trace elements in the environment that can pose serious risks both to wildlife and human health. This highlights the importance of studying the role of sewage discharges in the contamination of aquatic systems, especially in rocky shores, since part of our food resources is directly collected from coastal waters. For this purpose, the accumulation of trace elements (Cu, Zn, Pb, Ni, Co, Cd, Fe, Mn, and As) by edible molluscs (Mytilus galloprovincialis, Patella ulyssiponensis, and Phorcus lineatus) was compared between one sewage-impacted area and two reference areas.

This study suggests that the concentrations of trace elements in the soft tissues of the selected molluscs can be affected by the presence of sewage discharges, and that limpets seem to be the best bioindicator. Moreover, the sewage pollution increased the concentrations of As in the mollusc species, emphasizing its potential damaging effects on natural systems and on edible species.

Key Words:

• molluscs
• trace elements
• sewage
• human health
• Portuguese coast

Additional information

Funding

This work was supported by FCT (Fundação para a Ciência e Tecnologia) through a PhD grant to Joana Cabral-Oliveira (SFRH/BD/48874/2008), with funds from POPH (Portuguese Operational Human Potential Program), QREN Portugal (Portuguese National Strategic Reference Framework), and MCTES (Portuguese Ministry of Science, Technology, and Higher Education).