Heavy metal bioaccumulation in mangrove benthic invertebrate Faunus ater (Linnaeus, 1758)

Vivian Jaeger

Heavy metal pollution is a common environmental stressor in coastal ecosystems, including mangrove forests. Cadmium (Cd) and lead (Pb) are non-essential heavy metals with high potential for toxic effects in mangrove benthos. The bioaccumulation via a contaminated food source (10 ppm Cd/ 80 ppm Pb) and adverse effects due to metal toxicity were measured in mangrove benthic gastropod Faunus ater (Linnaeus 1758) under laboratory conditions. After 6 weeks of treatment, soft tissue concentrations of cadmium and lead were significantly elevated in the Cd and Pb treatment groups, respectively, marking food consumption as a relevant pathway for metal uptake. Cd shows a bioaccumulation factor (BAF) of >1, while BAF of Pb is <1, indicating a higher bioaccumulation rate of cadmium. However, consumption rate, respiration and locomotion of F. ater did not exhibit statistically significant treatment-dependent changes. Regulatory mechanisms that suppress toxic effects may be present in F. ater. Further research is needed to understand the exact fate of both metals in the species and in order to draw implications regarding the effects heavy metal pollution has on mangrove fauna.