Research on polluted channel of Pb and Cd in the field vegetables

The soi1 monitoring of the field vegetables shows that the whole contents and the effective contents of Pb and Cd in polluted area are lower than those in non-polluted region，but the contents of Pb and Cd in lettuce and green Chinese onion and shallot are obvious higher than those in non-polluted region．They have coherency about the whole contents and the effective contents of Pb and Cd in soils，and in the dry and fresh weight of vegetables，Pb and Cd have coherency，it shows that the Pb and Cd pollution have a synchronizing step．In the same place，the effective contents of Pb in soils and the contents of Pb in vegetables，the effective contents of Cd in soils and the contents of Cd in vegetables all have not coherency，showing that the Pb and Cd pollutions in vegetables has no relation with soils．The vegetables in non-polluted area haven’t exceed standard samples and the sample exceed standard rate in polluted are8 is 40％ ．and the vegetable breeds of exceed standard display the leafy-vegetable type such as lettuce，green Chinese onion，pigweed，celery and so on．So the main pollution channel of Pb and Cd in field vegetables comes from the atmosphere pollution．