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Data on elemental heavy metals Cd, Cr, Cu, Ni, Pb, and Zn in river sediments in Taiwan, China, Japan, India, and Vietnam during the years 1999 to 2009 was reviewed and discussed. The results denote that the average composition of Cd in river sediments in the studied countries ranged from 0.07 to 79.1 mg/kg and the average composition of Cr ranged from 20.5 to 211 mg/kg. The average composition Cu ranged from 8.45 to 1,070 mg/kg and the average composition Ni ranged from 16.9 to 181 mg/kg the studied countries during the years of 1999 to 2009. Additionally, the average composition of Pb ranged from 11.4 to 230 mg/kg and the average composition of Zn ranged from 21.5 to 58.6 mg/kg. Moreover, the results show that the sources of heavy metal pollution came mainly from a variety of anthropogenic activities which include domestic and industrial wastewater, as well as e-waste recycling, chemical, electric plating, and refining industries. [ABSTRACT FROM AUTHOR]