Rice samples were purchased from the OuYa Supermarket
(Changchun, China), and the producing areas were Dehui, Meihekou,
Yushu and Wanchang of Jilin province and Wuchang of
Helongjiang province in China, respectively. All the samples were
powdered using a cyclone mill and passed through a 40 mesh
sieve. The blank samples were spiked with carbamate standards
at 1 lg g1 for optimisation and validation experiments.