On September 19, 2012, the U.S. FDA released results of its testing of nearly 200 samples of rice and rice products, finding appreciable levels in many products, although the amounts in only a few exceed the cancer-warning threshold of the State of California (10 mcg per daily serving).
The FDA has been monitoring arsenic levels in rice for more than 20 years, but its researchers are now better able to measure whether those levels represent inorganic arsenic (considered more toxic) or organic arsenic (considered less toxic), apparently spurring the new wave of testing.
Among different types of rice, the lowest levels of inorganic arsenic were found among “basmati” rice products, most of which contained about 2 to 3 mcg in a 45 gram serving of rice — equal to about 1 cup of cooked rice. The highest levels of organic arsenic (10 to 11 mcg per serving) were found in several “brown” rice products which were labeled as “long grain” or “whole grain.” Unlike white rice, brown rice includes the bran which, while high in fiber, also contains higher concentrations of arsenic than the more starchy part of the grain. The country of origin (USA or India) did not appear to coincide with higher or lower levels. A summary of the findings is available online, although brand names are not identified.