Determination of perchlorate and its distribution in unhusked rice in China

Perchlorate concentrations in 387 unhusked rice samples from 15 main producing provinces/municipality in China were investigated by high-performance liquid chromatography–tanden mass spectrometry. The results indicated that perchlorate displays a mean level of 17.17 μg/kg in unhusked rice samples. Intriguingly, we also found that perchlorate is mainly observed in rice husk among these collected unhusked rice samples, while less observed in rice bran and milled rice. Specifically, the perchlorate levels in rice were found in the husks (73.61%), bran (10.09%), and milled rice (19.52%), respectively. Our results indicated that there is no significantly perchlorate exposure risk in edible milled rice.