Citizen science usually isn’t this personal. In 2011, roughly 65,000 Japanese citizens living near the crippled Fukushima Daiichi Nuclear Power Plant started measuring their own radiation exposure in the wake of the Tōhoku earthquake and tsunami. That’s because no one, not even experts, knew how accurate the traditional method of estimating dosage—taking readings from aircraft hundreds of meters above the ground—really was. Now, in a first-of-its-kind study, scientists analyzing the thousands of citizen readings have come to a surprising conclusion: The airborne observations in this region of Japan overestimated the true radiation level by a factor of four.
by Ashley Braun
Originally in Hakai Magazine
Published: 16 Jan 2017
A heavily-exploited Japanese fish found sanctuary after the 2011 Fukushima earthquake.
You won’t catch any three-eyed mutant fish off the coast of Japan these days, but in the wake of the 2011 earthquake and tsunami you also won’t have a problem finding flounder, the latest species to suddenly flourish in a nuclear disaster zone after humans have been pushed away.
No Fukushima contamination was found in any of the 14 fish Alaskan fish samples that were collected between February and September 2016, according to the Alaska Department of Environmental Conservation. The results, released on the Alaksa DEC website, show that the sampled herring, cod, and pollock, halibut, and salmon did not have any detectable levels of 131I, 134Cs (the Fukushima fingerprint radionuclide with a half-life of ~2 years) or 137Cs in the tissues. These samples were from across Alaskan waters from Southeast to Bristol Bay and the Aleutian archipelago and the Bering Sea. Results from 2016 are similar to their results from 2015 and are part of the network of institutions monitoring for Fukushima radiation in marine waters and seafoods.
The average minimum detectable concentrations for these Alaskan samples on this gamma spectrometer were 63.7 Bq kg-1, 2.1 Bq kg-1, and 1.9 Bq kg-1 respectively for 131I 137Cs, and 134Cs. While InFORM does not analyze for 131I, those detection thresholds for cesium are 2-3 times higher than are typical for our biotic monitoring program. This may be due to either a smaller sample size or a shorter time in the gamma spectrometer for the Alaskan samples, but the result remains that levels are well below those where intervention is needed (intervention levels for 131I = 170 Bq kg-1 and 134Cs + 137Cs = 1200 Bq kg-1 according to the US Food and Drug Administration). InFORM monitoring in 2016 found 9 salmon (out of 123) from BC and Yukon rivers with detectable levels (where the minimum detectable concentrations were less than 1 Bq kg-1) of 137Cs after a six hour detector run. These nine samples are currently being freeze-dried for an extended, 2 week long, detection run. Results from this additional analysis are expected probably mid-late spring 2017.
An interesting aspect of these 2016 Alaskan samples is that this was the first time a field-deployable gamma spectrometer has been sent by the US Food and Drug Administration to a site for local analyses of samples. Data from the spectrometer were then electronically sent to FDA scientists for analysis. The thought is that this model could be used in the event of nuclear emergency to allow for more rapid analyses of environmental samples.
Alaska DEC will continue monitoring fish samples for Fukushima radiation for at least 2017 and possibly beyond.
Last evening I spoke at the monthly meeting of Surfrider Vancouver Island, one of InFORM’s non-governmental organization partners, to provide them with an update on our most recent results and progress. Surfrider VI helps to coordinate our citizen science volunteers who sample coastal seawater every month to monitor for Fukushima derived contamination along our beaches from Victoria in the south to Lax Kw’alaams in the north of BC. Surfrider VI is primarily responsible for sampling in Port Renfrew BC which is on the southwest coast of Vancouver Island.
I was pleasantly surprised by Lynn Wharram (Volunteer Coordinator and Combing the Coast BCU team lead) who had produced a short video chronicling her family collecting InFORM’s August 2016 seawater sample from the dock near the Port Renfrew Hotel. You can watch the video below.
You can read more about our citizen science program methods here, our NGO partners here , and our citizen science volunteers here. Thanks again to our volunteers and to Surfrider VI for all the work they do. Go and check them out if you are interested in ocean health (and surfing).
No Fukushima contamination was found in any of the 7 fish Alaskan fish samples that were collected during February and March of 2016. The results, released on the Department of Environmental Conservation website, show that the herring, cod, and pollock sampled did not have any detectable levels of 131I, 134Cs (the Fukushima fingerprint radionuclide with a half-life of ~2 years) or 137Cs in the tissues. These samples follow on their similar results from 2015 and are part of the network of institutions monitoring for Fukushima radiation in marine waters and seafoods. Continue reading No Fukushima radiation found in 2016 Alaskan fish