Radiation Testing of Seafood by Washington State Seafood Companies: Radioactive Strontium and Cesium

Vital Choice Wild Seafood and Organics, a Washington state seafood company, has been conducting radiation testing on Pacific ocean fish since 2012. Recently they released the results of testing for strontium 90 in King Salmon, Sockeye Salmon, and Albacore Tuna, which are posted here with their permission.

No strontium found:
Article dated 1/09/2014 
Results PDF 
"Last summer, the first reports appeared suggesting that a longer-lived radionuclide called strontium 90 (Sr-90) was leaking from the stricken nuclear plant.
So to ensure safety, we sent more fish to be tested for Sr-90, in the fall of 2013."

Strontium testing was performed by Pace Analytical Services, Inc. Review was performed by SGS North America, Inc.

Received on 10/30/2013. Analyzed on 11/12/2013.

Sockeye Salmon   -0.00130 ± 0.0210 pCi/g (MDC 0.0513 pCi/g) or -0.0481 ± 0.777 Bq/kg   (MDC 1.8981 Bq/kg) 
King Salmon           0.0228 ± 0.0292 pCi/g (MDC 0.0635 pCi/g) or 0.8436 ± 1.0804 Bq/kg (MDC 2.3495 Bq/kg)
Albacore Tuna       -0.0151 ± 0.0167 pCi/g (MDC 0.0456 pCi/g) or -0.5587 ± 0.6179 Bq/kg (MDC 0.6247 Bq/kg)

Results are shown as the activity ± uncertainty. The original results in pCi/g are followed by values converted to Bq/kg (1 pCi = 0.037 Bq).
Entire fish, including skin and bone, was tested according to Vital Choice, which is important as strontium accumulates in the bone.
 MDC is minimum detectable concentration. (Also described as MDA, minimum detectable activity). (Note 1)

Vital Choice seafood harvest areas are described on this page.

    ”All of our Pacific seafood – salmon, sablefish, halibut, cod, prawns, shrimp, Dungeness crab, mussels, and clams – is caught or harvested off Alaska, Washington State, Oregon, and British Columbia (BC), between 4,000 and 5,000 miles east of the nuclear plant.
    The sole exceptions are albacore tuna and king crab. Our albacore is caught off Midway Island, and our king crab is caught in the Bering Sea. Both areas are located about 2,500 miles east of the plant.”

Vital Choice has also done three rounds of radiation testing for iodine 131 and cesium 134 and 137.

1st test reported on 3/29/2012
"Eurofins Laboratories tested 15 species of fish and shellfish for cesium-134, cesium-137, and iodine-131, and found none."

Cesium 134: None to trace levels (MDA 1.0 Bq/kg)
    Most species  <1.0 Bq/kg
    Albacore 1.4 Bq/kg
    Halibut 1.3 Bq/kg

The trace levels found in our albacore and halibut are less than 15% of the maximum combined level of Cesium 137 + 134 normally found in fish (10 Bq/kg). (See Note 2)

And those trace levels are just 0.1% of the FDA’s level of concern (DIL) for combined Cesium 137 + 134 levels in foods (1200 Bq/kg). (See Note 3)

Cesium 137: None detected (MDA 1.0 Bq/kg)
Iodine 131: None detected (MDA 2.0 Bq/kg)
This means that all seafood tested contained less than 1.2% of the FDA’s Derived Intervention Level (DIL) for Iodine 131 (170 Bq/kg). Iodine 131 decays to safe forms within about two weeks after its creation. (See Note 3)

2nd test reported in September 2012
"Eurofins Laboratories tested our Pacific albacore and our Alaskan halibut, sockeye salmon, and cod. They found no cesium-134 or iodine 131, and only a barely detectable, clearly safe level of Cesium 137 in a sample of cod."

Cesium 134: None detected (MDA 1.0 Bq/kg)
Cesium 137: Cod 1.2 Bq/kg (MDA 1.0 Bq/kg)
Iodine 131: None detected (MDA 2.0 Bq/kg).

3rd test reported in September 2013
"Eurofins Laboratories tested our salmon (pink, king, sockeye, silver), tuna, cod, halibut, and sablefish for cesium-134, cesium-137, and iodine-131, and found none."

Cesium-134: None detected (MAD 1.0 Bq/kg)
Cesium-137: None detected (MDA 1.0 Bq/kg)
Iodine-131: None detected (MDA 2.0 Bq/kg)

*****

Also, Loki Fish Company in Seattle, Washington, just released their radiation test results conducted by Eurofins Analytical Laboratories.
A family owned and operated business, Loki Fish Company harvest wild salmon and halibut from southeast Alaska and Puget Sound. 

January 7, 2014 post by Loki Fish Company "No Elevated Levels of Radiation Found in North Pacific Salmon Samples"
Test results 
"Tests were conducted on Pink, Keta, Coho, Sockeye and King salmon from southeast Alaska, and Pink and Keta salmon from Puget Sound."

Cesium-134: Alaskan Pink Salmon 1.2 Bq/kg (MDA 1.0 Bq/kg)
Cesium-137: Alaskan Keta Salmon 1.4 Bq/kg (MDA 1.0 Bq/kg)
Iodine-131: None detected (MDA 2.0 Bq/kg)

*****
Note 1: For reference, MDC for strontium testing by the Japanese Fisheries Agency was in the range of 0.01-0.04 Bq/kg.

Note 2: Is it true that maximum of 10Bq/kg of combined Cs134 AND Cs137 can be found in fish under the normal circumstance? Should there be any Cs134 normally found in fish? Upon an inquiry, Vital Choice said this information came from Eurofins. According to this study, no Cs134 was detected and Cs137 was 1.4 Bq/kg in Pacific Blue Fin Tuna in 2008).

Note 3: US FDA's DIL (Derived Interventional Level)  is 160 Bq/kg for strontium 90, 170 Bq/kg for iodine 131, and 1,200 Bq/kg for cesium 134 and 137 for any food. Standard limits for radioactive cesium in Japan are 100 Bq/kg for general food and 50 Bq/kg for infant food and milk, taking into account the contribution from radioactive strontium and plutonium, etc. It should be noted that these limits are considered too high by those who believe internal radiation doses have stronger effects than equivalent external radiation exposure doses. For instance, report by foodwatch and German IPPNW (International Physicians for the Prevention of Nuclear War) calls for lowering of EU cesium limits of 600 Bq/kg for all foodstuffs and 370 Bq/kg for baby food and milk products to 16 Bq/kg and 8 Bq/kg, respectively.

Furthermore, on the Vital Choice information page, the section called "Radiation experts see no cause for concern," refers to a study called "Evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood.

Excerpt from the abstract:
"The additional dose from Fukushima radionuclides to humans consuming tainted PBFT in the United States was calculated to be 0.9 and 4.7 µSv for average consumers and subsistence fishermen, respectively. Such doses are comparable to, or less than, the dose all humans routinely obtain from naturally occurring radionuclides in many food items, medical treatments, air travel, or other background sources. Although uncertainties remain regarding the assessment of cancer risk at low doses of ionizing radiation to humans, the dose received from PBFT consumption by subsistence fishermen can be estimated to result in two additional fatal cancer cases per 10,000,000 similarly exposed people."

First of all, 
the internal dose described in μSv (microsievert) and applied to general population is misleading, as sensitivity to radiation can vary with age and gender. In addition, comparison of manmade fission products, such as radioactive cesium, to natural background radiation, such as radioactive potassium in bananas, is also misleading as such comparison tolerates and nearly justifies the environmental existence of the fission products. One must ask the question, "Should it really be there?" Also, exposure to medical diagnostic and therapeutic radiation (internal or external) is not exactly "background," and it is not harmless as seen in this study. Air travel is hardly comparable to ingestion of cesium as the former is external exposure while the latter internal.

One must understand these distinctions, often blurred in convenient explanations, to be able to make an intelligent decision about whether or not to consume contaminated foodstuff. Since there is no safe dose of radiation, it is ultimately an individual decision whether or not to accept the risk. However, a higher vulnerability of certain populations, such as babies, infants, children and pregnant women, and women with reproductive potential, should be taken into consideration. 

Note 4: In both Vital Choice and Loki Fish tests, Cs 134 was found alone without Cs 137 in some fish. This seemed odd, as the presence of Cs 134 is the signature for Fukushima radiation contamination as opposed to Cs 137 alone which could be due to past nuclear testing. When Vital Choice was asked about this, they had no information on it. They just stated that Eurofins was expert in radionuclide testing. 

No comments:

Fukushima Thyroid Examination November 2024: 284 Surgically Confirmed as Thyroid Cancer Among 345 Cytology Suspected Cases

  Overview      On November 12, 2024,  t he 53rd session of the Oversight Committee  for the  Fukushima Health Management Survey  (FHMS) con...