EVERYTHING is synthetic these days. Used to be the fear was breathing smoke. Now they have discovered toxins on gear and equipment are a problem. Departments worldwide are pushing to clean gear THOROUGHLY after EVERY fire. Not 10 years ago, having dirty gear was a badge of honor/ courage. Now, it is flat out stupidly! I have had old timers remind me that back in the day, fires were wood and cotton products. Personally, I have seen fires with PURPLE and GREEN smoke. On top of ALL that, Firefighters have VERY poor sleep habits and diets too. Over a career, it