Abstract |
Davao region is the most urbanized and industrialized part of Mindanao, Philippines. However,
there are limited investigations of heavy metal contamination in the region's marine environment,
particularly in bivalves. One of the major shellfish commodities in the area is Pegophysema philippiana,
locally known as imbao. Thus, this study was conducted to determine the cadmium, lead, and mercury
concentrations in the flesh of mangrove clams in selected areas of the region with substantial harvest and
evaluate the health risk associated with consumption. Heavy metal concentrations were assessed using
cold vapor atomic absorption spectroscopy for mercury and atomic absorption spectroscopy for cadmium
and lead. The estimated daily human consumption of mangrove clams was determined through a social
survey. The results revealed that Cd, Pb, and Hg concentrations in mangrove clams in Malita, Mati, and
Bangaga were below the tolerable limits established for bivalves, but Cd and Pb in Sta. Cruz slightly
exceeded the permissible levels. The local consumption rate of mangrove clam in four sites showed a
significant difference (p<0.05), with the highest value recorded in Baganga (12.40 g day-1
ind-1
) and the
lowest in Sta. Cruz (1.31 g day-1
ind-1
). The health risk indices, such as estimated daily intake (EDI) values,
were far below the provisional tolerable daily intakes (PTDI) established by authorized agencies, while the
target hazard quotient (THQ) and total target hazard quotient (TTHQ) were less than one. Thus, no health
risks were associated with consuming mangrove clams in the four sampling areas. However, further
investigation and monitoring of the mangrove clams and other fishery commodities are encouraged to
secure consumer鈥檚 safety |