Fukushima's Bluefin Tuna Reaches California's Shores and Raises Fears

By Theodora Filis

The plan to release treated wastewater has been in the works for years, with the environment minister declaring in 2019 there were “no other options” as space runs out to contain the contaminated material.

Bluefin tuna only spawn in the western Pacific, and often head east towards California following food sources. These days, they bring with them “low levels” of radiation.

Along the California coast concerns that this is the result of the tsunami-damaged Fukushima nuclear power plant have many people worried. Scientists believe these were young tuna that left Japanese waters approximately a month after the power plant disaster, last year.

The real issue is a hydrogen isotope called radioactive tritium, which cannot be taken away. There is currently no technology available to do so.

Diluting the wastewater might not be enough to reduce its impact on marine life. Pollutants like tritium can pass through various levels of the food chain – including plants, animals, and bacteria – and be “bioaccumulated,” meaning they will build up in the marine ecosystem.

The world’s oceans are already under stress from climate change, ocean acidification, overfishing, and pollution. The last thing it needs is to be treated like a “dumping ground". 

Potential risks won’t just affect the Asia-Pacific region. One 2012 study found evidence that bluefin tuna had transported radionuclides – radioactive isotopes like the ones in nuclear wastewater – from Fukushima across the Pacific to California.

Many scientists pointed out that even if this is common practice among nuclear plants, there just isn’t enough research into the impact of tritium on the environment and on our food items.

The release of wastewater could further damage Fukushima’s global and regional reputation – once again hurting fishermen’s livelihoods, many argue, “It really feels like they made this decision without our full consent.”