author(s)
James Paul B Velasco, Cresencio C Cabuga Jr, Brigette Y Orog, Julius Anthony M Leones and Joycelyn C Jumawan

abstract
Muscles of Johnius (Johnieops) borneensis and sediments from Pagatpatan, Lower Agusan River Basin, Butuan City were tested for the determination of Cadmium (Cd), Copper (Cu), Lead (Pb), Nickel (Ni) and total mercury (tHg) from April to May 2015. Samples were analyzed, and the results show that the mean concentrations of the different heavy metals across three sampling sites are in the order of Pb> Ni> Cu> Cd> tHg. For the sediment samples, the mean concentrations of the different heavy metals across three sampling sites are in the order of Ni> Cu> Pb> Cd> tHg. Pb, Cd, Ni, and tHg exceeded their standard allowable limits for fish muscles and sediments established by USEPA and FDA. Results of the Pearson-correlation of fish muscles vs. Sediments show a slightly positive (r = 0.5960) value which suggests that heavy metal concentrations in the fish muscles are not directly influenced by the sediments.