Assessment of trace metal bioaccumulation by Avicennia marina (Forsk.) in the last remaining mangrove stands in Manila Bay, the Philippines.

Concentrations of lead (Pb), copper (Cu), zinc (Zn), and cadmium (Cd) were evaluated in the sediments, roots and leaves of a mangrove species (Avicennia marina) in Las Piñas-Parañaque Critical Habitat and Ecotourism Area (LPPCHEA), Manila Bay. The concentrations showed a general pattern of Zn > Pb > Cu > Cd in sediments, Cu > Pb > Zn > Cd in roots and Cu > Zn > Pb > Cd in leaves. The trace metal concentrations in both sediments and plant tissues were below contamination threshold levels. Based on computed bioaccumulation indices, A. marina could be used for the phytostabilization and phytoextraction of Cu and Cd. The LPPCHEA mangrove ecosystem is an ecologically important ecosystem that will limit the spread of trace metals to the surrounding environment.