Bioaccumulation of Selected Heavy Metals in Bivalve Molluscs from Northeastern Vietnam: Implications for Safe Seafood Utilization

Rapid industrial growth, urbanization, and agricultural activities have led to the discharge of large volumes of pollutants into coastal environments, raising levels of metals such as arsenic (As), cadmium (Cd), and mercury (Hg) in water and sediments. Bivalve molluscs, such as Meretrix lyrata and Saccostrea glomerata can accumulate high amounts of toxic heavy metals in their tissues that pose potential risks to human health. They are frequently used as bioindicators due to their filter-feeding behavior and high accumulation potential. This study evaluates heavy metal accumulation in bivalve molluscs from Northeastern Vietnam, including Quang Ninh Province and Hai Phong City. In this study, a systematic literature review was conducted, combined with a bibliometric analysis, to synthesize and evaluate data on heavy metal accumulation in bivalve molluscs from Northeastern Vietnam. The analysis results showed bio-concentration factors exceeding 1,000 for As, Cd, and Hg in certain species, particularly in samples from Quang Ninh Province. Meanwhile, sediment accumulation factors (BSAF) were lower, suggesting that waterborne pathways predominantly contribute to heavy metal uptake. These findings highlight significant food safety risks due to toxic metal accumulation in seafood resources, emphasizing the urgent need for continuous monitoring and the establishment of local safety standards. The study provides important scientific evidence to support marine environmental management and public health protection.