Monitoring of arsenic contents in domestic rice and human risk assessment for daily intake of inorganic arsenic in Korea

Rice can be the major contributor to exposure of inorganic arsenic (iAs). A total of 485 domestic rice (polished rice, n = 368; husked rice, n = 117) samples produced in 2014 were determined for total arsenic (tAs) and As species. The determination of As species was conducted by HPLC-ICP-MS. AsIII was the major detected species. AsV, DMA, and MMA were occurred in lower level in both types of rice. In polished rice, iAs represented 43–91% of tAs: tAs = 0.088 ± 0.021 mg/kg; iAs = 0.060 ± 0.013 mg/kg. In husked rice, iAs ranged from 55% to 91% of tAs; tAs = 0.160 ± 0.042 mg/kg, iAs = 0.114 ± 0.029 mg/kg. The iAs level of polished rice samples was below the current maximum limit of the Chinese and German standard (0.2 mg/kg for inorganic arsenic in milled rice). Also, husked rice samples did not exceed the standard for iAs. Average dietary exposure to iAs from polished rice consumption was calculated as 0.17 ± 0.21 μg/kg·bw/day which was 8.09% level of Provisional Tolerable Weekly Intake. The result obtained in the present study provide a reference data of iAs in Korean rice for the establishment of safety standards.