Tag Archives: 134-Cs

CBC News: Fukushima nuclear pollution hasn’t hit B.C. shore, says researcher Jay Cullen

Cullen expects nuclear pollution from Fukushima will hit B.C.’s beaches eventually

By Daybreak North, CBC News Posted: Mar 11, 2015 3:33 PM PT Last Updated: Mar 11, 2015 9:57 PM PT

Ocean currents act as a conveyor, carrying debris and radiation-contaminated water from Japan towards North America. Ocean currents act as a conveyor, carrying debris and radiation-contaminated water from Japan towards North America. (NOAA)

Four years after a massive earthquake struck Japan, creating a nuclear disaster in Fukushima, research shows nuclear pollution is making its way towards B.C., but isn’t affecting fish.

“According to all the measurements that we’ve made thus far, and with our partner Health Canada who have been making measurements of fish since 2011, we’ve yet to detect that marker isotope for fish caught along the coast,” Jay Cullen, a University of Victoria professor, told Daybreak North’s Carolina de Ryk.

The earthquake that struck off the coast of the Tohoku region in northeastern Japan on March 11, 2011, set off a monster wave, up to seven metres high, that crashed over the coast, causing massive damage.

The seawater from the tsunami breached the Fukushima Daiichi nuclear plant, disabling its cooling system, causing a nuclear meltdown that the country is still trying to clean up. Altogether, the disaster killed 19,000 people and displaced more than 300,000.

Cullen, who leads a network to monitor the impact of the nuclear pollution caused by the disaster, said his team is looking for two specific cesium isotopes released from Fukushima.

“Atmospheric fallout reached the BC coast in the weeks following the meltdowns according to Health Canada monitoring stations. Transport by prevailing ocean currents was detected as early as 2012 about 1,500 kilometres offshore, and in 2014 we were detecting that contamination — fingerprint element that could only come from Fukushima on the continental shelf of British Columbia,” he said.

The team he works with is also analyzing samples sent in by residents along B.C.’s coast, which he said haven’t turned up any trace of Fukushima radiation.

He expects the nuclear pollution will hit B.C.’s beaches eventually, and he said researchers like himself will continue to monitor the impact that will have.

 

Dramatic Decrease of Fukushima Derived Radionuclides in the Northwest Pacific Ocean 2011-2012

By Jay T. Cullen

A schematic view of the formation and subduction of mode waters in the North Pacific

The purpose of this diary is to report on a recently published (Jan 2015) open-access, peer reviewed study which examined the activities of 137Cs (half life 30.2 yr), 134Cs (half life ~2.1 yr) and 90Sr (half life ~28.8 yr) in the northwest Pacific off the coasts of Japan and China. The diary is part of a ongoing effort to communicate the results of scientific research into the impact of the Fukushima Dai-ichi nuclear disaster on environmental and public health. Men and colleagues report on how activities of these fission produced isotopes changed between three research expeditions in June 2011, December 2011 and June 2012. Activities in seawater decreased dramatically through time for all three isotopes consistent with very high release rates measured from the Fukushima site in March-April 2011 followed by ongoing but many orders of magnitude (10,000 – 100,000 fold) lower releases from the site thereafter. By 2012 the impact of the Fukushima releases could be still be detected in most samples for Cs isotopes however 90Sr distributions were much more uniform with the highest measured activity only slightly above the pre-Fukushima background. These results are consistent with:

  1. the relatively small source term for 90Sr from compared with the Cs isotopes from Fukushima as determined by measurements of air, soil and water after the disaster
  2. the much lower Fukushima derived activities for these isotopes in the eastern Pacific off of North America being measured given decay and mixing of the contamination as it is transported by ocean currents

Continue reading Dramatic Decrease of Fukushima Derived Radionuclides in the Northwest Pacific Ocean 2011-2012