Residues of p-DDE which are the main degradation product of DDT (Stephens et al. 1994) were detected in the surface soil samples from Canola Field (Table 2). The level of p-DDE was 0.04% of the total extractable organic matter in October and November 2004. The detection level of p-DDE increased to 0.12% in December 2004 and it is also found in soil samples from Wheat Field with relative concentration of 0.06%. The levels decreased again in January 2005 to 0.09 and 0.03%. This change in the detection level of p-DDE in soil may be due to the increase of the water content of the soil, because by increasing the water content of the soil as a result of rain causes a decrease in the extractable level of p-DDE (Lalah and Wandiga 1998).