Assessment of biomonitoring potential of contamination and bioavailability of heavy metals using red blood cockle Tegillarca granosa: Experimental field-based transplantation study

This study evaluates the potential of red blood cockle Tegillarca granosa as a biomonitor for heavy metal contamination in coastal environments, with a focus on the differential bioaccumulation patterns across three sites: Teluk Kemang (TK), Pasir Panjang (PP), and Port Dickson (PD). Four major findings emerged from the analysis. First, T. granosa demonstrated significant variations in metal accumulation, with PD exhibiting the highest concentrations of Zinc (Zn), Copper (Cu), and Iron (Fe). This confirms the species' sensitivity to varying pollution levels and highlights PD as the most contaminated site among the three. Second, strong correlations between metal levels in the environment and their accumulation in the cockle’s soft tissues underscored its effectiveness in reflecting the bioavailability of contaminants, particularly for Zn and Cu. This finding validates the use of T. granosa as an effective bioindicator of environmental metal exposure. Third, the study highlighted the role of cockle shells as indicators of long-term exposure, with consistently higher metal concentrations observed at PD. This suggests persistent environmental contamination in this area and demonstrates the value of shell analysis in assessing chronic pollution. Finally, the stepwise multiple regression analysis revealed complex interactions between environmental media and bioaccumulation processes, emphasizing the need for a comprehensive approach to biomonitoring. These interactions indicate that bioaccumulation in T. granosa is influenced by multiple environmental factors, necessitating an integrated monitoring strategy. These findings support the use of T. granosa as a reliable indicator species for monitoring heavy metal pollution and assessing ecological risks in coastal ecosystems.