Microbial and Heavy Metal Contamination in Edible Bivalves from the Suez Canal: A Potential Health Risk

Abstract

decussatus) collected from the Suez Canal near Ismailia, Egypt. The focus was on seasonal variations in contamination levels and the associated health risks to the local population. Bivalve samples were analyzed across four seasons (2023–2024) to identify harmful microorganisms and trace metal concentrations. Naturally occurring bacteria were isolated and identified, revealing prevalent species such as Streptococcus faecalis, Aeromonas spp., and Vibrio spp. These bacterial strains were purified and evaluated for their pathogenic potential. Mortality experiments demonstrated that S. faecalis and Vibrio spp. exhibited high pathogenicity, while Aeromonas spp. showed moderate pathogenicity. In parallel, atomic absorption spectrophotometry was used to measure the concentrations of heavy metals—Fe, Cu, Mn, Zn, Pb, and Cd—in the bivalves’ soft tissues. The results showed that the annual mean concentrations of Fe, Cd, Pb, Cu, and Zn exceeded FAO/WHO safety thresholds, particularly in winter, raising serious concerns regarding seafood safety. Overall, the findings highlight that bivalves function effectively as bioindicators of environmental contamination and underscore the need for strengthened monitoring and regulatory measures in the region to protect public health.