Dr. Robert Metzger, Radiation Safety Engineering, Inc, American Chemical Society 2013 Meeting (emphasis added): Contamination of food imports to the United States in the early days after the Fukushima accident… Contaminated food imports into the US from Japan were first observed in our laboratory on March 30, 2011, with several products exceeding the FDA DerivedIntervention Level (DIL) for Cesium and Iodine…
Dr. Metzger’s presentation excerpts, Feb 8, 2014:
- First observed food… contamination was found on March 30… a Sushi import was found to be contaminated with 131I
- April 5, a shipment of Koji powder was… heavily contaminated with 60Co, 124Sb, 131I, 132Te, 134Cs and 137Cs… This, and subsequent samples, exceeded the FDA [DIL]
- By July, the 1-131 had largely decayed away and the primary concern was foods that were known concentrators of some of the isotopes. The sample of the dried green tea leaves below has Cesium concentrations at 1/3 of the FDA DIL [~400 Bq/kg]
- By July, the impact of the water releases were observed in harvests of seaweed… The sample [tested] is about 1/3 of the FDA DIL for Cesium [~400 Bq/kg]
- Published results indicate [FDA] found little to no observable contamination… There are several possible explanations… We were testing samples while the accident was still in progress and therefore saw problems before the FDA started testing seriously
- Imported food products contaminated with fission products… were detected starting in late March… Conscientious importers tested their imported foods and destroyed any food that was found to be contaminated, even at levels well below the FDA DIL
FDA, May 3, 2011: FDA has not detected any longer‐lived radionuclides, such as Cs‐137, in any fish imported from Japan… FDA is performing field examinations… on approximately 40% of the seafood products… shipped to [US]… March 21, 2011 to April 25, 2011, 3,496 examinations were performed. To date, no field examinations have shown levels above background. FDA is also randomly sampling selected entries and subjecting them to laboratory analysis. To date, no gamma‐ray emitting radionuclides of concern have been detected.
FDA, Mar. 2014: FDA has no evidence [of Fukushima] radionuclides… in the US food supply at levels that would pose a public health concern… FDA has tested 1,345 [samples]… two were found to contain detectable levels of Cesium, but… posed no public health concern… 1) Ginger Powder… collected April 2011; 2) Green Tea Bag… collected August 2013… During this time, routine monitoring of the domestic US food supply was also conducted and included roughly 1,500 samples… No contamination was detected during this routine monitoring.
According to an Oct. 30 CBS interview with a professor involved with UC Berkeley-affiliated Kelp Watch: “There’s never zero risk” to someone exposed to radioactive material no matter the level.