Metol is a contraction of Para-Methylaminophenol Sulphate, and since Methyl is usually pronounced with a long e(Meethile), then I suppose Metol should be as well.(posted 9016 days ago)However, I don't think anybody's going to laugh in your face if you pronounce it with a short e: Unless they're Chemists or Photographers they won't know what the hell you're talking about anyway.