4. Conclusion
A new GCeMS/MS method in combination with one step derivatization
with BAL was developed for the speciation of iAs in polished
rice. Reaction temperature and time have dramatic impacts on
both BAL-iAs reaction and reduction of iAs (V) to iAs (III). The GC-MS/
MS method can provide the speciation of iAs in rice products with
2.5min running time. The establishedmethod showed a satisfactory
linearity (r2 > 0.998) in a wide concentration range (0.2e100 ppb),
very low LOD (0.08 pg) and LOQ (0.2 pg), excellent accuracy and a
high precision, and high intra- and inter-day repeatability. The
sample preparation step was also very simple (one step derivatization
followed by extraction and shoot). The method was successfully
applied to measure the iAs in polished rice. The mean iAs content in
the Korean polished rice (n ¼ 27) was 66.1 mg kg1 with the range of
37.5e125.0 mg kg1. This represents the first report on the GCtandem
mass spectrometry in conjunction with the one step derivatization
with BAL for the iAs speciation in rice.