MBL Scientist Finds Carbon Dioxide Makes Poison Ivy Worse: “Carbon dioxide is getting a bad rap lately for all that it contributes to global warming. Now rising CO2 levels may exacerbate another problem: poison ivy. New research by an MBL (Marine Biological Laboratory) scientist indicates that the prevalence, and itchiness, of poison ivy may get worse if carbon dioxide levels continue to increase. “Do what you should be doing already – avoid poison ivy,” said Jacqueline E. Mohan about the problem. Mohan, a postdoctoral scientist at the MBL’s Ecosystems Center, was the lead author for a study on the effects of increased carbon dioxide on poison ivy (Toxicodendron radicans). The ivy grown under high carbon dioxide grew twice as much over five years as the ivy exposed to today’s level of the greenhouse gas. Also, ivy grown in high carbon dioxide produced a more allergenic version of urushiol, the compound that causes itchy rashes for about 80% of people exposed to poison ivy…Besides the blistering rashes caused by poison ivy, scientists are interested in Mohan’s research for another reason: the choking of the world’s forests. Poison ivy is in a class of plants called woody vines. Around the world, woody vines are flourishing to the point where they can smother young trees, which are the “forests of the future,” said Mohan. Fifty to 100 years from now, if the level of carbon dioxide continues to rise and carbon dioxide promotes growth in woody vines, “what do we expect our forests to look like?” said Mohan.”