Study on unnecessary elements in leafy vegetables of polluted farmland to heavy metals at around Shahr-e-Qods

Contamination of soil and crops, including leafy vegetables consumed by heavy metals due to improper management of farming systems in the world, human society has provided a cause of concern. In this research, sampling from 10 farms for the study of heavy metals in leafy vegetables including lettuce (Lactuca sativa), spinach (Spinacia oleracea) and parsley (Petroselinum crispum) has been done. In order to perform the sampling of leafy vegetables at the end of each field season 5 randomly sampled from the beginning, end and middle of each plot were harvested and then each field contamination by heavy metals has been studied. The results showed that the effect of heavy metals treatment was significant on leafy vegetables. Mean comparison showed that the highest Pb (0.17 mg/kg), Hg (0.02 mg/kg) and Cd (0.13 mg/kg) in Spinach and highest Ni (0.10 mg/kg) was achieved Lettuce. Also, the lowest Pb (0.11mg/kg) and Cd (0.10 mg/kg) in Lettuce, Ni (0.08 mg/kg) in Parsley and finally Hg heavy metal (0.02mg/kg) was lowest in Lettuce and Parsley.