Medaka fish Oryzias javanicus Bleeker as bio-indicator of lead content in waters

Abstract

An increase of heavy metal used in various products has lead to an increase of its pollution in water column elsewhere. Previous studies have shown that member of medaka fish is widely used as bio-indicator of pollution. Various medaka fish have been used in environmental as medical studies. The present study aims to observe capability of medaka fish Oryzias javanicus Bleeker as bio-indicator of lead [Pb] content in waters. Fish was collected from the mouth river of Jeneberang South Sulawesi and acclimatized at the Medaka Study Centre of Hasanuddin University. In order to study capability as bio-indicator, the fishes as test animals was treated with different concentration that of 0; 0.01; 0.03 and 0.05 mg/L Pb. Test animals were kept in media containing Pb for ten days before assessing their metal content. Pb content in animals was calculated after treatments. Composite method was applied for Pb content in medaka fish, in which fish was crushed and proceed to metal content analysis using EDXRF spectrofotometer. The result indicates that medaka fish Oryzias javanicus Bleeker survives at threshold concentration 0.05 mg/L Pb, respectively. We conclude that Oryzias javanicus can be used as bio-indicator of lead content in waters.