Why Vape Juice Turns Dark or Brown Since their introduction in Europe in 2006 and the U.S. in 2007, the use of e cigarettes a.k.a., vapes has skyrocketed. A recent review from researchers in Australia found the results Why Does Vape Juice Turn Brown? Understanding the Evolution of Vaping Devices Illicit Vapes and E Cigarettes Flood Stores as F.D.A. Struggles to Combat Imports The New York Times What's really inside vapes? We pulled them apart to find out