I can’t recall where but I read something about southern US rice (especially Texas) having high levels of arsenic. California rice was reported as safer
On cotton fields lead arsenate was used as a pesticide to kill boll weevils. Some of that land now is rice fields. USA rice is marked Product of USA to differentiate from foreign crop. California grown is marked California to differentiate it from US south grown rice.
https://www.consumerreports.org/cro/magazine/2012/11/arsenic...