Marijuana-related calls to poison control centers in Washington and Colorado have spiked since the states began allowing legal sales last year, with an especially troubling increase in calls concerning young children.

New year-end data show that the Rocky Mountain Poison and Drug Center received 151 calls for marijuana exposure last year, the first year of retail recreational pot sales. That was up from 88 calls in 2013 and 61 in 2012, the year voters made marijuana legal for adults over 21.

Calls to the Washington Poison Center for marijuana exposures jumped by more than half, from 158 in 2013 to 246 last year.

Public health experts say they are especially concerned about children accidentally eating marijuana edibles. Calls involving children nearly doubled to 48 in Washington involving children 12 or under and to 45 in Colorado involving children 8 or under.