Determination of Bioconcentration Factor of Heavy Metal (loid)s in Rice Grown on Soils Vulnerable to Heavy Metal (loid)s Contamination

Abstract

There is an increasing concern over heavy metal (loid) contamination of soil in agricultural areas including paddy soils. This study was conducted to determine the bioconcentration factor (BCF) for heavy metal (loid)s to brown rice grown in paddy soils vulnerable to heavy metal (loid)s contamination, for the quantitative health risk assessment to the residents living nearby the metal contaminated regions. The samples were collected from 98 sites nationwide in the year 2015. The mean and range BCF values of As, Cd, Cu, Ni, Pb, and Zn in brown rice were 0.027 (0.001 ~ 0.224), 0.143 (0.001 ~ 2.434), 0.165 (0.039 ~ 0.819), 0.028 (0.005 ~ 0.187), 0.006 (0.001 ~ 0.048), and 0.355 (0.113 ~ 1.263), respectively, with Zn showing the highest. Even though the relationship between heavy metal (loid) contents in the vulnerable soils and metal contents in brown rice collected at the same fields was not significantly correlated, the relationship between log contents of heavy metal(loid)s in the vulnerable soils and BCF of brown rice wes significantly correlated with As, Cd, Cu, and Zn in rice. In conclusion, soil environmental risk assessment for crop uptake should consider the bioconcentration factor calculated using both the initial and vulnerable heavy metal (loid) contents in the required soil and the crop cultivated in the same fields.Correlation coefficients between log contents of As (A) and Cd (B) in the vulnerable paddy fields by arsenic contamination and bioconcentration factors of brown rice collected at the same fields.