WASHINGTON (AP) — The Food and Drug Administration may consider new standards for the levels of arsenic in rice as consumer groups are calling for federal guidance on how much of the carcinogen can be present in food.

So far, FDA officials say they have found no evidence that suggests rice is unsafe to eat. The agency has studied the issue for decades but is in the middle of conducting a new study of 1,200 samples of grocery-store rice products — short and long-grain rice, adult and baby cereals, drinks and even rice cakes — to measure arsenic levels.

Arsenic is thought to be found in rice in higher levels than most other foods because it is grown in water on the ground, optimal conditions for the contaminant to be absorbed in the rice. There are no federal standards for how much arsenic is allowed in food.