Heavy metal contamination is caused by various sources, such as industrial processes, manufacturing, disposal of industrial and domestic refuse, and agricultural practices.(1) Campbell et al. compared natural and anthropogenic quantities of trace metals emitted to the atmosphere and showed that around 15 times more Cd, 100 times more Pb, 13 times more Cu and 21 times more Zn are emitted by human activities than by natural processes.(2) The main copper contamination sources in soils are pig and poultry manures, pesticides and metal finishing and microelectronics by products. In Thailand, 150-250 ppm copper, in the form of copper sulfate, is added to pig feed as a growth rate regulator. In some cases, zinc is also mixed with copper which causes an increase of these elements in pig waste (approximately 400 ppm zinc and 800 ppm copper).(3) Using contaminated pig manure as a soil amendment could cause soil pollution and the accumulation of heavy metal to a toxic level through out the food chain.