title: Accumulation and distribution of cadmium and lead in wheat (Triticum aestivum L.) grown in contaminated soils from the oasis, north-west China.
abstract: BACKGROUND
  Crops grown in soils contaminated by heavy metals are an important avenue for toxic metals entering the human food chain. The objectives of our study were to investigate the accumulation and distribution of cadmium (Cd) and lead (Pb) in wheat plants cultivated in arid soils spiked with different doses of heavy metal, as well as bioavailability of these metals in the contaminated arid soils from the oasis, north-west China.
  
  
  RESULTS
  The concentrations of Cd in the roots of wheat plants were about 5, 14 and 8 times higher than those in the shoots, shells and grains, respectively. The concentrations of Pb in the roots were about 23, 76 and 683 times higher than those in the shoots, shells and grains, respectively. Grains contained 11-14% and 0.1-0.2% of Cd and Pb found in roots of wheat plants. The bioconcentration factor (BCF) is the ratio of metal concentration in plant tissues and metal concentration in their rooted soils. The average BCF of Cd and Pb in grains was 0.6270 and 0.0007. Cd and Pb contents in different parts of wheat plants mainly correlated with the bound-to-carbonate metal fractions in contaminated arid soils.
  
  
  CONCLUSIONS
  The preliminary study indicated that Cd and Pb were predominantly accumulated and distributed in wheat roots and shoots, and only a small proportion of these metals can reach the grains. The carbonate fractions mainly contributed to Cd and Pb bioavailability in contaminated arid soils.
authors.affiliation: Key Laboratory of Western China's Environmental Systems of the Ministry of Education (MOE) & College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Zhao-Wei
authors.initials: ZW
authors.lastname: Wang
authors.forename: Zhong-Ren
authors.initials: ZR
authors.lastname: Nan
authors.forename: Sheng-Li
authors.initials: SL
authors.lastname: Wang
authors.forename: Zhuan-Jun
authors.initials: ZJ
authors.lastname: Zhao
mesh_terms: D001682:Biological Availability; D002104:Cadmium / Q000378:metabolism*; D002254:Carbonates / Q000378:metabolism; D002681:China; D002523:Edible Grain / Q000378:metabolism*; D020387:Food Chain; D005506:Food Contamination; D007854:Lead / Q000378:metabolism*; D018514:Plant Structures / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000378:metabolism*; D014908:Triticum / Q000378:metabolism*
chemical_list: D002254:Carbonates; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead