Rice is grown in water flooded fields which allow it to absorb arsenic from soil or water much more effectively than other crops. according to the report, rice grown in California, is likely to have lower arsenic rates than rice grown in the South. (In the United States 15% of rice is grown in California, 49% in Arkansas, and the remaining rice grown in Louisiana, Mississippi, Missouri and Texas.
To reduce your risk, it is recommended that you wash rice thoroughly before cooking it, cook the rice with a lot of extra water to absorb arsenic and/or pesticide residue and drain the rice at the very end before serving it. (or boil it like you would when making pasta.)
Click here to read the Consumer Union study.