ABC News Between 2000 and 2020, reports to poison centers for child and teen marijuana use increased by 245%, according to a new study from the Oregon Health and Science University. The researchers analyzed more than 330,000 reports in the National Poison Data System over the last 20 years and found the increase in marijuana rates was the most of any substance, with the … [Read more...] about Poison center reports for child marijuana use rose 245% in last 20 years: Study