Determination of total arsenic content and arsenic speciation in different types of rice

The objectives of this study was to examine the amount of total arsenic and arsenic speciation in different types of rice from two areas in Korea using inductively coupled plasma/mass spectrometer (ICP-MS) and high performance liquid chromatography-ICP/MS (HPLC-ICP/MS) and estimate the potential health risk from rice consumption. Brown rice (0% of degree of polishing, DOP%) contained the highest amount of total arsenic followed by 5, 7 and 10 DOP% white rice. Among the arsenic species, As(III) was predominantly detected in brown (0 DOP%) and white rice (10 DOP%), with concentrations ranging from 28.51 +/- 0.71 to 51.91 +/- 1.13 mu g/kg in region A and from 62.1 to 130.4 mu g/kg in region B. While estimating the daily arsenic exposure from consumption of polished rice, the expected daily exposure of inorganic arsenic from brown and 10 DOP% white rice was found to be below benchmark dose modeling value for a 0.5% increased incidence of lung cancer (BMDL0.5) (3.0 mu g/kg bw per day). Therefore, arsenic in rice, particularly, As(III), tends to accumulate in the outer layer of rice.