Noxious fumes are a type of air pollution that can be caused by a variety of sources, such as industrial processes, vehicle exhaust, and burning of fossil fuels. The two crossword solutions for the term 'noxious fumes' are 'VAPORS' (6 letters) and 'miasmas' (7 letters). VAPORS are gaseous substances that are released into the atmosphere, while miasmas are noxious VAPORS or gases that are believed to cause disease. Both terms refer to the same type of air pollution, but they are used in different contexts.