Growing use of synthetic marijuana cannabinoids is to blame for a 229% increase in suspected poisonings earlier this year, the Centers for Disease Control and Prevention reported today. Between January and May 2015, U.S. poison centers in 48 states reported receiving 3,572 calls related to synthetic cannabinoid use, compared to about 1,085 calls during the same time period in 2014. The 2015 figures included a spike of 1,501 calls in April, and 15 reported deaths, a three-fold increase over the five deaths reported in 2014. Synthetic cannabinoids include a range of psychoactive chemicals that are sprayed onto plant material, and then smoked or ingested. The findings suggest that synthetic cannabinoids “pose an emerging public threat … and a need for greater public health surveillance and awareness, targeted public health messaging, and enhanced efforts to remove these products from the market,” the report said.