Lead and Cadmiun Concentrations in the Catfi sh Pangasius Polyuranodon (Bleeker 1852) from the Siak River,Riau Province,Indonesia

During the last decades, increasing development of industries, urban communities and agriculture near aquatic ecosystems lead to pollution, especially in the developing countries of Southeast Asia. Due to trace metal pollution through increasing development and human activities near aquatic ecosystems, there is a growing risk of toxic metal exposure to fi sh and through their consumption also to humans. Therefore, the investigation of the chemical quality of fi sh for consumption, particularly the concentrations of toxic metals, is important for human health. We investigated the trace metal concentrations of lead (Pb) and cadmium (Cd) in different tissues of the catfi sh Pangasius polyuranodon from fi ve areas of the Siak River in order to evaluate the potential for human health hazards resulting from fi sh consumption. Mean concentrations of Pb and Cd in gills (0.14 and 0.22, respectively), livers (0.11 and 0.18, respectively) and muscles (0.14 and 0.15, respectively) of P. polyuranodon were below national and international standards. Pb levels in gills and muscles were close to the national food standard at one sampling site and Cd concentrations in the gills were found to be at the national food standard at the same site. Only at one site, Cd concentration in the liver slightly exceeded the national, but not the international food standard. The overall results indicate that the edibles parts of P. polyuranodon in the Siak are only slightly contaminated by Pb and Cd and do not represent a risk for human consumption in regard to the two investigated trace metals. However, the special biogeochemistry of the blackwater river Siak might enhance bioaccumulation of toxic metals and more research is needed in regard to other toxic metals, seasonal availability of these metals, other consumed fi sh species, as well as fi sh age or size dependent accumulation of toxic metals.