Although the twin tragedies are fundamentally different in many ways, there are also some disturbing similarities between the 2010 Deepwater Horizon oil spill and last year’s post-earthquake, nuclear meltdown at Fukushima, Japan. Both episodes were rooted in fundamentally unsound solutions to an industrialized nation’s quest for easy energy solutions. Both accidents were downplayed for days by officials who sought to cover up the full extent of the danger. And today, both the Gulf of Mexico and the contaminated zone around the Japanese nuclear plant face a long, difficult road to environmental recovery — even as government and industry try to pretend that the crisis is in the past.
Another grim similarity is that both the oil that flowed for days from the crippled rig in the Gulf and the radioactive water that spilled from the containment facilities at Fukushima pose serious threats to the fragile chain of marine life. In recent weeks we’ve been understandably more focused on the ongoing legacy of the Deepwater Horizon spill, with the two-year anniversary marked by reports of fishermen catching eyeless shrimp or seriously diseased fish — and that’s in the areas that haven’t become dead zones for marine life.
But health concerns also persist in the waters off Japan. The Fukushima disaster was the largest accidental release of radiation into the ocean in the history of mankind. Experts reported that the levels of one key radioactive isotope — cesium-137, which has a half-life of 30 years – peaked at more than 50 million times normal levels when contaminated water surged from the earthquake-damaged plant. There is particular concern about effect of radioactivity in the ocean sediment where some key species of marine life feed, but scientists have been debating how serious the long-term impact might be.
That’s why a startling news report out of California this weekshould serve as a wake-up call. Researchers have discovered significant levels of radiation linked to the Fukushima disaster in large bluefin tuna that swam some 6,000 miles from the contaminated waters of Japan to the U.S. Pacific Coast. The levels of cesium in these mighty sport fish — roughly 10 times higher than any levels that had been discovered previously off California — was a big surprise to scientists who reported the discovery in this week’s Proceedings of the National Academy of Sciences. They said they were not expecting the impact of the disaster to last for so long in such large fish. Said Nicholas Fisher, one of the researchers: “We were frankly kind of startled.”
The background, according to one news report:
Five months after the Fukushima disaster, Fisher of Stony Brook University in New York and a team decided to test Pacific bluefin that were caught off the coast of San Diego. To their surprise, tissue samples from all 15 tuna captured contained levels of two radioactive substances – ceisum-134 and cesium-137 – that were higher than in previous catches.
To rule out the possibility that the radiation was carried by ocean currents or deposited in the sea through the atmosphere, the team also analyzed yellowfin tuna, found in the eastern Pacific, and bluefin that migrated to Southern California before the nuclear crisis. They found no trace of cesium-134 and only background levels of cesium-137 left over from nuclear weapons testing in the 1960s.
The experts believe that the radiation is partly the result of tuna swimming in the contaminated waters off Japan and partly from feeding on marine life such as krill and squid which was poisoned by the aftermath of the nuclear disaster. The thing that really surprised these scientists was how high the levels on contamination remained after the fish migrated across the world’s largest ocean. “That’s a big ocean,” Fisher said. “To swim across it and still retain these radionuclides is pretty amazing.”
The news coverage notes that bluefin tuna is considered a seafood delicacy in Japan, where the bulk of it is consumed. The big concern is that the tuna tested by Fisher’s team were only exposed to the radiation from Fukushima for roughly one month. But the next group of tuna to migrate to California will have spent considerably more time in the contaminated Pacific — and so the damage could be much worse.
What scares me the most is this: Here in the United States, we’ve already seen how federal regulators have been eager to cover up the worst impacts from the Deepwater Horizon disaster on the seafood that comes from the Gulf. So who can we trust to keep us safe from the threat of radiation poisoning from the Pacific catch?
To read a news account of the discovery of radioactive bluefin tuna: http://www.huffingtonpost.ca/2012/05/28/radioactive-tuna-japan_n_1551042.html
To read what scientific experts have learned about radioactive contamination near Fukushima, read: http://www.medicaldaily.com/news/20111209/8199/japan-earthquake-tsunami-fukushima-radiation-radioactive-nuclear-plant-fallout-ocean.htm
To read my past coverage of seafood contamination from the Deepwater Horizon spill: http://www.stuarthsmith.com/seafood-surprise-eyeless-shrimp-crabs-with-lesions-%E2%80%93-and-bigger-final-settlement-offers-from-bp