Arsenic in North American grown rice has been made worse than it otherwise would be because arsenic was used extensively for 100 years+ as a pesticide to combat the boll weevil in cotton plantations. As a result, large amounts of pesticide-arsenic have accumulated in soils in southern states where cotton was grown. Much  former cotton growing land is now used to grow rice. Most supposedly healthy brown rice is grown in southern states and thus is likely to have high arsenic content. Brown rice grown in California is safer as there's no California history of arsenic use as an agricultural pesticide and no arsenic accumulation in soils there. 

But I've had problems finding rice I could be sure was grown in Calif. Even if the distributing company's listed as located in  Calif. that doesn't necessarily mean the rice was grown there. And I can't find brown rice at a reasonable price grown outside North America. So, I've given up "healthier" brown rice, and switched to Indian
white basmati.