Offensive-odor substance in the evil-smelling fish from the sea polluted by petroleum and petrochemical industrial waste. 1. Identification of offensive-odor substance

For the purpose to reveal the substance as the source of offensive odor of the fish from the sea facing petroleum and petrochemical industries, analyses have been made on the sea water, industrial wastes, offensive odor fish meat and the eels kept in the sea or industrial waste for a certain period, by means of gas chromatography, infrared, and ultraviolet absorption spectrophotometries and mass-spectrometry. Observations revealed toluene as a possible main source responsible for the bad smelling of the fish. Finally, by analysing the meat extract of the fish kept in the sea water containing toluene and by the same smell as that of the offensive odor fish from the off-shore of the industries, it has been definitely confirmed that toluene is the very substance that imparts the offensive odor to fish. The activated sludge process proved to be an effective method to remove toluene from the industrial wastes. A discussion was made on the aliphatic carbohydrate as the possible source of the offensive odor of fish.