Nuclear disaster touches Valley

Radiation from meltdown in Japan found in a fish taken from Okanagan Lake, but at level far too low to pose any health risk

Radiation associated with Japan’s 2011 nuclear disaster has been detected in a salmon taken from Okanagan Lake.

It’s the first time cesium-134, the “fingerprint” isotope from the Fukushima power plant, has been found in a fish in Canadian waters.

Scientists say the level of radiation was 10,000 times lower than Health Canada safety guidelines, which is nowhere near a significant risk to consumers.

“For perspective, you would need to eat 1,000 to 1,500 kilograms of salmon with this level of contamination in a short period of time to increase your radiation dose by the same amount as a single fivehour cross-country airplane flight,” Jay Cullen, a chemical oceanographer who detected the cesium-134 in the fish taken from Okanagan Lake, says in a press release from the University of Victoria, where he works.

Cullen leads the In FORM coastal network, which monitors marine radioactivity off the B.C. shoreline.

A team of researchers led by Cullen determined that eight of 156 fish taken from B.C. waters tested positive for trace levels of cesium-137, also a man-made isotope, but not necessarily from Fukushima.

Cesium-137 is still present in the environment from testing of nuclear weapons in the 20th century and the Chornobyl nuclear reactor meltdown in Ukraine in 1986.

Cullen’s team did more intense analysis to determine if cesium-134, associated only with the ill-fated Fukushima nuclear plant, was also present in the eight fish.

“We took these same eight fish and measured them for 60 times as long as we normally do to look for the Fukushima fingerprint,” Cullen says. “This is analogous to cupping your hand behind your ear to pick up a whisper across the room.”

The radiation plume from the Fukushima disaster has spread throughout the northeast Pacific Ocean, from Alaska to California. Maximum levels of contamination are expected near the coast this year and in 2018.

The INFORM network involves scientists in Canada and the U.S., health experts, nongovernmental organizations and citizens along the B.C. coast who assist with the monthly collection of water, and annual collections of fish and shellfish samples for analysis.

This work supplements measurements taken farther offshore by Fisheries and Oceans Canada.

“As the highest concentrations from (Fukushima seaborne radiation) plume arrive in the next few years, we’ll continue to monitor radioisotope levels and what kinds of risks they pose,” Cullen says.

“Levels measured now and predicted at their peak are unlikely to present a significant health risk to the marine ecosystem or public health in B.C.,” Cullen says.

The Fukushima nuclear power plant had a catastrophic meltdown following an earthquake and subsequent tsunami. Six years later, efforts continue to identify and remove melted radioactive fuel inside the plant.