Amazing. It looks like TTX (tetrodotoxin, a potent voltage-gated sodium channel blocker well-known to electrophysiologists) is not made by the pufferfish (which I had always assumed), rather it is from the bacteria/food consumed by the fish.
Decades earlier, another Japanese scientist had identified fugu’s poison as tetrodotoxin, a neurotoxin that leaves victims mentally aware while they suffer paralysis and, in the worst cases, die of heart failure or suffocation. There is no known antidote.
Researchers surmised that fugu probably got the toxin by eating other animals that carried tetrodotoxin-laden bacteria, developing immunity over time — though scientists then did not rule out the possibility that fugu produced the toxin on its own.
By this year, Mr. Noguchi had tested more than 7,000 fugu in seven prefectures in Japan that had been given only feed free of the tetrodotoxin-laden bacteria. Not one was poisonous.
“When it wasn’t known where fugu’s poison came from, the mystery made for better conversation,” Mr. Noguchi said. “So, in effect, we took the romance out of fugu.”
Aside from the interesting science, it appears there is also a small Japanese “industry” (de-ttx? detox?) seriously affected by TTX-free fugu. More after the jump
But what could be seen as potential good news for gourmands has instead been grounds for controversy: powerful interests in the fugu industry, playing on lingering safety fears, are fighting to keep the ban on fugu livers even from poison-free fish.
“We won’t approve it,” Hisashi Matsumura, the president of the Shimonoseki Fugu Association and vice president of the National Fugu Association, said of the legalization of fugu liver. He added, “We’re not engaging in this irrelevant discussion.”
Acting as a giant clearinghouse, this port city in southwestern Japan buys fugu from all over Japan and China, guts it and expertly removes its poison before shipping it throughout Japan and as far as New York. Though Shimonoseki’s share has fallen in recent years, it still controls about half of Japan’s fugu market.