Factors of Soil Properties and Elements in Tissues Influencing on Extent of Arsenic Accumulation in Brown Rice

Abstract

Recently, As-contaminated soil management has started dealing with phytoavailable As content instead oftotal As content in soils. Phytoavailable As content is known to consider food safety more than themanagement of the environment. This study aims to predict As content in brown rice using phytoavailable Asconcentration in soil and soil properties and to see the relationship between element contents in tissues and Asin brown rice. As-contaminated soils were collected, and their total and phytoavailable As content and soilproperties were analyzed. Mehlich3 extraction method was used for phytoavailable As analysis. After theanalysis, correlations among total and phytoavailable As concentrations in soils, As content in rice and soilproperties were analyzed. Then, a prediction model of As content in brown rice was developed throughmultiple stepwise regression. Also, correlation analysis between nutrients and As contents in rice wasconducted to identify the factors affecting As accumulation in brown rice. The modelling equation forestimating As concentration in brown rice was [Log (As in brown rice) = 2.45 + 0.13 × Log (As_Mehlich3) –0.99 × Log (CEC) + 0.50 × Log (avail.-P)] (r = 0.49, p < 0.001). Soil avail.P concentration and CEC were validvariables for As accumulation in brown rice. In addition, Cu, Zn, Mo and Na in shoot were revealed toinfluence governing translocation of As from shoot to grain.