The "strange odor" in Kanagawa Prefecture continues. Sunday Station thoroughly investigated theories such as "oil tank leakage" and "sign of a major earthquake". We focused on the Nagasawa district of Yokosuka City, located on the east side of the Miura Peninsula. We also had Professor Mitsuda Megumi, an expert in "odor research", accompany us during the interview. Verification 1 "Blue tide" theory This is the state of the "blue tide" in Tokyo Bay in 2017. A large amount of plankton carcasses decompose, causing a lack of oxygen. This is a phenomenon in which the surface of the sea looks pale blue. Mr. Iwasaki, a local fisherman, says he smelled the "strange odor" twice, once on his boat and once at home. "It was definitely a rubber smell. It smelled like rubber was being burned." He has been a fisherman for over 20 years and has experienced "blue tides" many times, but... "It's completely different." According to Kanagawa Prefecture, there have been no reports of blue tides occurring within the prefecture this year. Verification 2 "sign of a major earthquake" theory The Miura Peninsula is home to several active faults. According to Professor Takahashi of Ritsumeikan University, the odor can also occur when rocks rub against each other or when plates begin to peel off. Chemical substances found in gasoline vapors, such as isopentane and pentane, were detected in the air collected in both Yokosuka and Yokohama. Do these occur as a precursor to an earthquake? "It's probably most likely gasoline-derived." "If this is all there is to the odor, I don't think it's an earthquake-derived problem." Verification 3: "Gas tanker release" theory In front of the Nagasawa district is the Uraga Channel. This is the route used by tankers to pass from Tokyo Bay to the Pacific Ocean. Tankers are "released" when people enter the tank for inspection or repair, or when changing the type of cargo. After unloading cargo such as gasoline, air is blown into the tank to replace the air with dissolved components with outside air. Could this have been the cause of the odor? However, according to the tanker operating company union, "gas release" is usually done outside the bay. "Gas disperses in the atmosphere. Gas release is done all over the country, so it is unlikely that the odor problem occurs in only a few areas." Verification 4: "Oil tank leak" theory An oil tank at a refinery on the coast of Yokohama. Gasoline is stored in a "floating roof" tank. The height of the roof changes depending on the amount of gasoline. It is said that there is no gap between the gasoline and the roof, which prevents the generation of evaporative gas. "Since there is no exhaust equipment (with the floating roof type) in the first place, it is difficult to imagine (an odor occurring)." They say that they inspect the tank 10 times a day for any abnormalities. "When the odor was confirmed, the refinery received several inquiries about the matter." "After checking the inside of the equipment for any abnormalities, we responded that there were no particular abnormalities on the premises. [TV Asahi News] https://news.tv-asahi.co.jp