say they now support legalizing marijuana according to a recent poll. to date 11 states and the district of columbia have done it. new strains of marijuana are far stronger than in the past. carter evans looks at what can happen when people encounter this very potent pot. >> how long is your recovery going the take? >> a lifetime. >> reporter: 20-year-old colton says he got hooked on marijuana in high school when it became legal in colorado five years ago. but the cheers back then have turned into unintended consequences for colton and others much younger. >> typically young children around the age of two mostly getting into caregivers, whether it's parents, grandparents, babysitters' marijuana product, often edible products. >> reporter: dr. sam wang's findings from colorado's children's hospital are included in a new nationwide study, showing a 27% increase in children and teenagers getting emergency treatment for marijuana toxicity.