Assessment Of Heavy Metal Pollution Of Vegetables And Relevant Soils In Beijing

The results,which were obtained by investigation and assessmenton heavy metal pollution of vegetable cultivated soils and its relevantvegetables as well as comparing that of Beijing's indigenous vegetablesto external vegetables, were as follows:l. Average content of Cu. Zn. Pb and Cd in Beijing's vegetablecultivated soils was one time higher than the background values ofBeijing's agricultural soils. The content of Ni was higher than thebackground value,too.2. Bejing's vegetable cultivated soils were suffered from pollutionof Cd and Zn .And rates of samples exceeding standard of Cd and Znwere 8% and 2%,respectively.3. Beijing's indigenous vegetables were suffered from pollution ofPb,Cd and Cr, and Pb pollution was the most serious .The second wasCd. The nest was Cr. The exceeding standard rate of Pb was11.39%,which was as 11 times and 39 times as that of Cd andCr,respectively.4. Average rate of samples exceeding standard of Beijing'sindigenous vegetables followed the order of leaf vegetables(6.71%) >root tubers (5. l3%) >melons and hoits(4.67%).5. All of pollution indexes of Beijing's indigenous vegetables werenot more than l. The heaVy metal pollution status of Haidian. Fengtai' Shijingshan and Chaoyang of near Urban was more serious than thatof TongZhou. Daxing and Shunyi of outer suburbs.6. The heaVy metal pollution status of Beijing's indigenousvegetables was more serious than that of extemal vegetables.7. The daily intakes of heaVy metal in vegetable per caPita inBeijing were less than ADI. Howeref, the daily intakes of Pb and Cdwere l9% and l6% of ADI,respectively8. The concentrating ratio of heaVy metal was in the order of Cd>Cu>Zn>Pb>N >Cr. The concentrating ratio of Cd in aggPlan washighest. Beans round trellis. cucumber and wax guard were Cd's smallenrichInent vegetables. Tomato. raPe' radish and onion were Cd'smedial enrichInent vegetables.And aggPlan. chili. cabbage andChinese cabbage were Cd's high enrichment vegetables.