Traces of vanadium in higher-temperature combustion products and solutions form droplets of molten vanadates. These assault the passivation layers on metals and induce significant temperature corrosion, that's a concern specifically for interior combustion engines. Molten sulfate and guide particulates also have this sort of influence. 1970 – Tobacco makers https://broadfar.com/heated-tobacco-shaping-a-safer-sustainable-smoking-future/