2 research outputs found
Global sourcing of low-inorganic arsenic rice grain
Arsenic in rice grain is dominated by two species: the carcinogen inorganic arsenic (the sum of arsenate and arsenite) and dimethylarsinic acid (DMA). Rice is the dominant source of inorganic arsenic into the human diet. As such, there is a need to identify sources of low-inorganic arsenic rice globally. Here we surveyed polished (white) rice across representative regions of rice production globally for arsenic speciation. In total 1180 samples were analysed from 29 distinct sampling zones, across 6 continents. For inorganic arsenic the global x ~
x~
was 66 ÎŒg/kg, and for DMA this figure was 21 ÎŒg/kg. DMA was more variable, ranging from <â2 to 690 ÎŒg/kg, while inorganic arsenic ranged fromâ<â2 to 399 ÎŒg/kg. It was found that inorganic arsenic dominated when grain sum of species was <â100 ÎŒg/kg, with DMA dominating at higher concentrations. There was considerable regional variance in grain arsenic speciation, particularly in DMA where temperate production regions had higher concentrations. Inorganic arsenic concentrations were relatively consistent across temperate, subtropical and northern hemisphere tropical regions. It was only in southern hemisphere tropical regions, in the eastern hemisphere that low-grain inorganic arsenic is found, namely East Africa (x ~
x~
â<â10 ÎŒg/kg) and the Southern Indonesian islands (x ~
x~
â<â20 ÎŒg/kg). Southern hemisphere South American rice was universally high in inorganic arsenic, the reason for which needs further exploration