The U.S. Environmental Protection Agency is increasing radiation monitoring after milk tested positive for trace amounts of radiation from Japan.

The milk, with iodine-131, was found in California and Washington states.

Dairy cows probably ingested the iodine-131 after eating grass, or feed, that the isotope settled on after being blown here from Japan.

Officials insist the radiation levels are so low that the milk is still safe to drink.  However, the Fukushima Daiichi nuclear plant is emitting higher levels of radiation now, and the predominate wind direction is towards North America.