Influence of soil type and genotype on Cd bioavailability and uptake by rice and implications for food safety

• Published in: Journal of environmental sciences (China) Vol. 24; no. 9; pp. 1647 - 1654
• Main Authors: Ye, Xinxin, Ma, Yibing, Sun, Bo
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2012; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China%Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China%State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
• Subjects: bioavailability; cadmium; Cadmium - chemistry; Cadmium - metabolism; Cultivars; food chain; Food Contamination; Genotype; health risk; human health; Humans; hybrids; leaves; organic matter; Oryza - genetics; Oryza - metabolism; Oryza sativa; paddy soils; red paddy soil; rice; rice genotype; risk reduction; roots; Soil - chemistry; soil pH; Soil Pollutants - chemistry; Soil Pollutants - metabolism; stems; yellow clayey paddy soil; 吸收; 土壤类型; 基因型; 大米; 生物利用度; 红壤性水稻土; 镉（Cd）; 食品安全; red paddy soil; health risk; cadmium; yellow clayey paddy soil; rice genotype
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/s1001-0742(11)60982-0

Cadmium (Cd) entering the human body via the food chain is of increasing concern. This study investigates the effects of soil type and genotype on variations in the Cd concentrations of different organs of nine rice plants grown on two types of soils with two Cd levels. Cd concentrations in nine rice cultivars varied significantly with genotype and soil type (P < 0.01). The Cd concentration was higher in red paddy soil (RP) than in yellow clayey paddy soil (YP). The average Cd concentrations of different organs in three rice types were indica > hybrid > japonica for the Cd treatments and controls. The polished grain concentration in YP and RP soils had a range of 0.055–0.23 mg/kg and 0.13–0.36 mg/kg in the Cd treatment, respectively. Two rice cultivars in YP soil and five rice cultivars in RP soil exceeded the concentration limits in the Chinese Food Hygiene Standard (0.2 mg/kg). The Cd concentrations in roots, stems, and leaves were all significantly and positively correlated to that in polished grain in a single test. The Cd concentrations in polished grain were positively and significantly (P < 0.01) correlated with the calculated transfer factors of stem to grain and leaf to grain Cd transfer. The results indicated that the variations of Cd concentration in grain were related to Cd uptake and the remobilization of Cd from stem and leaf to grain. Also, the cultivars with a strong tendency for Cd-accumulation should be avoided in paddy soil with low soil pH and low organic matter content to reduce the risks to human health from high Cd levels in rice.