Is the high concentration of toxic arsenic in Red Rice of the Camargue linked to the generally positive fact that it has high concentrations of antioxidants?

BFHZ Förderprogramm zur Anbahnung bayerischer-französischer Kooperationen in der Forschung und Lehre FK 40 15

Red and black rice are exported from the Camargue, France, worldwide. As whole-grain varieties they are highly appreciated for their color and high concentrations of antioxidants (e.g. anthocyanins, flavones, procyanidins, carotenoids) in the bran. However, they also contain some of the highest concentrations of arsenic (on average 450 µg/kg, at maximum 730 µg/kg) which is a known human carcinogen. In light of the new EU limit of 200 µg/kg (effective from 01.01.2016 on) it is mandatory to better understand why especially the colored rice varieties seem to accumulate arsenic so well. Within the present small pre-project, we will determine whether there is a general linkage between arsenic concentration/speciation and quantity/type of bran-phytochemical or any other element or substance (Si, P, Fe; trace elements, GSH). We will sample 3 different colored rice varieties at 6 test sites that differ in soil composition, chemistry, and salinity at two different times (during tillering stage and immediately before harvest). Analysis will be done by IC-ICP-MS for arsenic speciation, LC-MS for bran-phytochemicals and GSH, and ICP-MS for total inorganic elements. All equipment is available at the University of Bayreuth and analytical costs can be covered. If our preliminary hypothesis can be confirmed, a full project will be designed as part of an ERC Grant. The overall goal will be to understand whether bran accumulation of beneficial phytochemicals and toxic arsenic are inherently linked and can potentially be regulated by environmental or genetic factors in a way that healthy whole-grain rice can be sold that meets the new EU regulations.