mephitic (adj.)

1620s, "of poisonous smell, foul, noxious," from Late Latin mephiticus, from Latin mephitis, mefitis "noxious vapor, a pestilential exhalation, especially from the earth" (also personified as a goddess believed to have the power to avert it), an Italic word of uncertain origin. English use of mephitis is attested from 1706.