Tag Archives: Salmon

Updated – No Fukushima radiation found in 2016 Alaskan fish

Alaska Department of Environmental ConservationNo 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.

2016 Biotic Monitoring Results: No Fukushima Contamination Detected in Salmon or Shellfish

Full results from 2016 InFORM salmon monitoring representing samples from 123 fish.
Results from 2016 InFORM salmon monitoring representing samples from 123 fish. Oceanic monitoring data were collected in 2015. Migration routes of various fish species are indicated with dashed lines.

More results from InFORM’s 2016 biotic monitoring results are now available and reveal that Fukushima contamination was not detected in sampled BC salmon after initial testing. These results are an update to the earlier report on the first 20 of the 123 fish donated by First Nations from 10 rivers in British Columbia and Yukon in 2016. Nine fish did have individual levels of 137Cs detected near the minimum detectable concentration (MDC). These levels (<0.7 Bq kg-1) are not known to present a significant health risk and are ~1,400x lower than the national and international action level (1000 Bq kg-1). For perspective, you would need to consume 1000-1500 kg of salmon at this concentration of cesium to receive the same radiation dose acquired during a single cross country flight. There has not been a significant increase to the total 137Cs concentration in BC salmon since InFORM monitoring began in 2014.

Continue reading 2016 Biotic Monitoring Results: No Fukushima Contamination Detected in Salmon or Shellfish

Should we be worried about Fukushima radiation?

ap-japan-nuclear
This Jan. 12, 2016 photo, shows No. 3 nuclear reactor, bottom, at Takahama nuclear power station in Takahama town in Fukui prefecture, northwestern Japan. Japan has restarted a nuclear reactor that burns plutonium-based fuel for power generation, first under the post-Fukushima safety rules. The No. 3 reactor at Takahama nuclear plant in western Japan, operated by Kansai Electric Power Co., becomes the first one using plutonium-uranium hybrid fuel known as MOX to go back online since the 2011 meltdowns at Fukushima. (Photo: AP)

by Mary Bowerman and Tracy Loew
USA Today
Published 9 Dec 2016

For the first time, seaborne radiation from Japan’s Fukushima nuclear disaster has been detected on the West Coast of the United States.

The levels are very low and shouldn’t harm people eating fish from the West Coast or swimming in the ocean, according to Ken Buesseler, a senior scientist at Woods Hole Oceanographic Institution. 

Continue reading Should we be worried about Fukushima radiation?

Pushing the Limit: Fukushima Fingerprint Isotope Found in Salmon from 2015

Results of the 2015 InFORM biotic monitoring program with updated results (larger, bold italics) where individual fish samples were reanalyzed in search of the Fukushima fingerprint isotope, 134-Cs.
Results of the 2015 InFORM biotic monitoring program with updated results (larger, bold italics) where individual fish samples were reanalyzed to determine the presence of the Fukushima fingerprint isotope, 134-Cs.

For the first time, the Fukushima fingerprint isotope, cesium-134 (134Cs; half-life ~ 2 years), has been detected at an extremely low level in a Canadian salmon by the InFORM project. The single sockeye salmon that tested positive was sampled from Okanagan Lake in the summer of 2015, according to scientists from the Radiation Protection Bureau at Health Canada, in cooperation with Fisheries and Oceans Canada and local First Nations.  The sample was one of a few (8 out of 156 total) individual fish that had trace levels of the longer lived  cesium-137 (137Cs) (30 yr half-life) that we reported on last winter. To determine if this trace 137Cs was from Fukushima or remnant from atmospheric weapons testing, InFORM reexamined these individual fish samples to see if extremely low levels of 134Cs may be present. The results of this extended analysis show that trace (0.07 Bq kg-1) levels of 134Cs were detected in one sample from Okanagan/Columbia River population. No 134Cs was detectable in the other samples. The observed levels remain well below the action level (1000 Bq kg-1) set by Health Canada guidelinesContinue reading Pushing the Limit: Fukushima Fingerprint Isotope Found in Salmon from 2015