Top soil used for the present study was purchased from Travis,
UK (Table 1). Soil was finely sieved to pass through a 2-mm
sieve for removal of foreign bodies and coarse particles. Soil
was air-dried after sieving and carefully weighed for spiking. A
soil certified reference standard (EnviroMAT-SCP SCIENCE)
was used during batches of analysis to check accuracy of results