The opening months of Colorado's first-in-the-nation recreational marijuana industry have seen a rise in fiery explosions and injuries as pot users try to make the drug's intoxicating oil in crude home-based laboratories. Since Jan. 1, when sales began, the state's only certified adult burn center has treated 10 people with serious injuries they suffered while making hash oil, compared with 11 in 2013 and one in 2012.