Category Archives: Coastal

Fukushima Contamination Detected at Shoreline in British Columbia

Satellite measurements of ocean temperature (illustrated by color) and the direction of currents (white arrows) help show where radionuclides from Fukushima are transported. Large scale currents transport water westward across the Pacific. Circles indicate the locations where water samples were collected. White circles indicate that no cesium-134 was detected. Blue circles indicate locations were low levels of cesium-134 were detected. Small amounts of cesium-134 have been detected in a water sample taken Feb. 19, 2015, from a dock in Ucluelet, British Columbia. (Woods Hole Oceanographic Institution)


The purpose of this post is to report that for the first time ocean borne contamination from Fukushima has been detected at the shoreline in British Columbia representing the first landfall in North America. Citizen scientists collected the sample on February 19, 2015 in the town of Ucluelet on the west coast of Vancouver Island Canada as part of our partner program Our Radioactive Ocean out of Woods Hole Oceanographic Institution in the USA. The isotope Cesium-134 (134Cs half life ~2 years) is an unequivocal fingerprint of Fukushima derived contamination because all other sources of this man made isotope (principally the Chernobyl disaster in 1986) are far enough in the past that 134Cs has long since decayed to levels too low to detect today. The Ucluelet sample contained 134Cs at 1.4 Becquerel per cubic meter (Bq m-3) of seawater and 5.8 Bq m-3 of the longer lived 137Cs (half life ~30 years). These levels were expected given measurements made by monitoring programs offshore and modeling studies which predict the arrival time and activity of Fukushima radionuclides. These levels of 137Cs and 134Cs, are well below internationally established levels that might represent a danger to human or environmental health. The next number of months will be very important to track the ocean transport of the contamination as citizen scientists with Our Radioactive Ocean and the InFORM project continue to collect samples up and down the coast of North America. Continue reading Fukushima Contamination Detected at Shoreline in British Columbia
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March 2015 InFORMal Monitoring Update

March2015 w Labels
InFORMal scientist monitoring results from January and February 2015

Forty water samples have been collected between October 2014 and March 2015 from 13 communities along the British Columbia coast. Results* from 19 samples are currently available.

Continue reading March 2015 InFORMal Monitoring Update

More Citizen Science Seawater Monitoring Results: No Fukushima Contamination Detected

By Jay T. Cullen

@JayTCullen and @FukushimaInFORM

February 16, 2015

What we found:

The absence of any detectable 134-Cs (an unambiguous fingerprint isotope of Fukushima contamination) in the seawater samples indicates that as of November 2014 these locations covering the length of the British Columbia coast have not be affected by ocean currents carrying Fukushima contamination.

The detection limit for 134-Cs averages ~0.2 Bq m-3

Newly added results come from seawater samples collected in collaboration with citizen scientists at the following locations in British Columbia, Canada during November 2014.

  1. Bamfield
  2. Masset, Haida Gwaii
  3. Lax Kw’alaams

Samples were processed and the amount of gamma emitting isotopes determined using a high purity germanium detector.  We look primarily for radioisotopes of cesium (134-Cs half life ~2 years and 137-Cs half life ~ 30 years) for the following reasons:

  1. 134-Cs has a half life that is short enough that all other human sources to the environment have decayed away making it an ideal tracer for Fukushima contamination
  2. next to the short lived Iodine-131 (half life ~ 8 days), Cs isotopes were released in greatest activity to the environment from Fukushima and would be most likely to represent a radiological health risk given their chemistry and propensity to be taken up by the biota
  3. other isotopes were released in much lower amounts from Fukushima relative to Cs (see other posts here and search for plutonium and strontium for example) and would therefore be much more difficult to detect
  4. because they are gamma emitters (unlike Pu isotopes and 90-Sr which emit alpha and beta radiation respectively) they are relatively easy and resource efficient to detect

The absence of detectable 134-Cs indicates that waters near these locations spanning the length of British Columbia have not been contaminated with Fukushima radioactive elements transported across the Pacific by prevailing currents as of Nov 2014. The presence of 137-Cs is due to historical sources of this human made isotope owing to atmospheric nuclear weapons tests in the 20th century and contamination from the Chernobyl disaster in 1986. You can read about the levels of 137-Cs in the North Pacific pre-Fukushima here.

More results will be published as they become available.

More Seawater Monitoring Results For Bella Bella, Port Hardy, Sandspit, Tofino and Vancouver BC: No Fukushima Contamination as of Nov. 24, 2014

By Jay T. Cullen

@JayTCullen and @FukushimaInFORM

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 Happy New Year from the InFORM team to all! Continue reading More Seawater Monitoring Results For Bella Bella, Port Hardy, Sandspit, Tofino and Vancouver BC: No Fukushima Contamination as of Nov. 24, 2014

First Seawater Monitoring Result From Victoria, BC: No Fukushima Contamination as of Oct. 15, 2014

By Jay T. Cullen

@JayTCullen and @FukushimaInFORM

On the granite blocks that make up the south side of Ogden Point Breakwater getting ready to take the first InFORM sample (photo by Katherine Maas)
On the granite blocks that make up the south side of Ogden Point Breakwater getting ready to take the first InFORM sample (photo by Katherine Maas)

What we found:

137-Cesium activity = 1.3 (+/- 0.1) Bq m-3 (Becquerel per meter cubed of seawater)
134-Cesium activity = Not Detected
Water Temperature = 10.5 C

The InFORM team collected a seawater sample in collaboration with citizen scientists in Victoria on Wednesday, Oct. 15 at the Ogden Point Breakwater (map shown below).  The sample was processed and the amount of gamma emitting isotopes determined using a high purity germanium detector.  We look primarily for radioisotopes of cesium (134-Cs half life ~2 years and 137-Cs half life ~ 30 years) for the following reasons: Continue reading First Seawater Monitoring Result From Victoria, BC: No Fukushima Contamination as of Oct. 15, 2014