Arsenic speciation varies with type of rice. Enviromental Science & Technology. April 16, 2008.New studies suggest that U.S. rice contains more methylated arsenic, a less toxic form of the metal, than rice from Europe and Asia does.Rice can be grouped into two types, depending on the form of arsenic in the grain, says Yamily Zavala, a research associate in John Duxbury’s laboratory at Cornell University. In two new papers published in ES&T DOI 10.1021/es702747y; 10.1021/es702748q), the researchers report that as arsenic levels rise, U.S. rice contains more methylated arsenic, the less toxic form, whereas rice grown in Europe and Asia contains the more toxic, inorganic arsenic.[ See ]