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Radioactive Japanese knives

I know this sounds insane but is there any merit to questioning the safety of Japanese steel? The internet abounds with discussions of food products being, let's say "tainted" bythe sad events at Fukashima. Can the same circumstances affect the ore (or whatever) from which knives are produced. I have some pre-Fukashima Shuns that are exquisite pieces of cutlery and I'd like to get more.
Someone please tell me I just have too much free time on my hands.

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  1. Yes. definitely too much free time. The problem with foods is that they have a nasty tendency to concentrate radioactivity.

    Also, we still have radioactive food in this country (milk) from atomic bomb testing. (Utah and Nevada,not everywhere)

    1. this is a complex and multi-part answer.

      in terms of health risk; more than likely, the knives don't pose a serious health risk.

      the fine print:
      first, depends where the knives are manufactured and shipped through. this year, for example, many countries have rejected japanese cars because they failed radiation inspections; so it is possible for inorganic items to carry contamination. the levels, though, vary widely.
      second, the real question is whether (relative to the overall environmental and global impact of the fukushima leak) the knife is even a relevant concern compared to things like fish, milk, seaweed, seaweed extracts, etc.

      contaminated? possible. how much? depends. enough to matter in the grand scheme of things? almost certainly not.

      (PS: i lived an hour or so drive from fukushima for 3.5 years before, during and after the quake, tsunami, and fukushima meltdown, so i have followed the whole thing pretty closely in a variety of languages, forums, and national media pipelines from several countries. this is my basic conclusion.)

      1 Reply
      1. re: chartreauxx

        FWIW, the cars rejected due to radiation contamination were all used cars, not ones newly manufactured in Japan during or after the Fukushima crisis.

      2. Don't worry about it. Go pick up more j-knives. Try other brands besides Shun as well, there's some great stuff out there waiting for you.

        1. for what its worth, there arent many knifemaking areas near the most effected areas... for example, the vast majority of factory produced knives from japan are coming from seki city in gifu prefecture... well away from radioactive concerns. Moreover, the steel used in your shuns is produced in fukui prefecture, again, well away from radioactive concerns.

          1. Thanks to all. Actually, I'm looking at a set of Globals for my son's wedding shower. Apparently, just a hair lighter, just as high metal quality and oh yea, a few bucks cheaper.

            1 Reply
            1. re: Moneemaniac

              if you're looking for good shuns, check out woot.com. and keep checking. WS offloads a ton, and when they're on "overstock" they are priced very reasonably.

              sample link:

            2. I am probably more concerns with Japanese steel being "tainted" when the two atomic bombs were dropped.

              1. Too much time on your hands.

                1. with just a peremptory look at the locations for Nippon Steel, I'm not seeing that there's that much steel production near Fukushima. (and most steel plants are located reasonably close to where the ores are found in the earth)

                  Given the fact that the ores are deep in the earth, I'm having a pretty hard time coming up with any logic that would support the contamination of steel by the radioactivity released by the Fukushima plant disaster.

                  1. I think you should be more concerned with the random bits of scrap that have been melted down and re-used:


                    3 Replies
                    1. re: Cynic2701

                      Steel in america goes through a radiation detector before it's melted down. A while back someone messed up big time, and they don't need recalls.

                      1. re: Chowrin

                        All steel everywhere? How about the "vintage" stuff that you can pick up in garage sales--do you think that as stringent of controls were in place 40-50 years ago?

                        I'm not, personally, too concerned; the background doses of radiation we receive is high enough that I'm not worried about using a slightly radioactive knife. Eat a few less bananas a year.

                        1. re: Cynic2701

                          I was talking about remelting plants. So everything new you buy with steel has been screened.

                    2. Wow! What a can of worms. I guess worry about everything or nothing at all. Does Amazon sell geiger counters?

                      1 Reply
                      1. the problem of radioactivity goes beyond japan.
                        the port of Los Angeles, in a random check, recently uncovered a radioactive batch of stainless steel pet bowls being imported from china.
                        do you really believe that the stainless steel in those pet bowls was not used for any other product?

                        the bowls, apparently had been distributed all over the US and have been recalled.

                        the supplier claims to be mystified about how the radioactive steel came to be used. . . . .

                        5 Replies
                        1. re: westsidegal

                          I wholeheartedly believe that the stainless steel in those pet bowls was not used to make knives.

                          1. re: sunshine842

                            Ya, lulz. Knives are made out of good steel, not some trash used to make a pet bowl.

                            1. re: sunshine842

                              sunshine843: AND i assume that you also believe that that contaminant ONLY made it into the steel that was used for the pet bowls? right?
                              maybe they put up a sign saying "radioactive material: please confine yourself to this one production run of pet bowls"
                              btw, the bowls were found ALL OVER THE U.S. after our port identified the problem.

                              1. re: westsidegal

                                I'm sure you're quite familiar with what the word 'assume' does.

                                I said nothing of the sort.

                            2. re: westsidegal

                              Here's Petco's notice about those bowls

                              "We don’t know for certain how it got into our product, but we believe it came from scrap metal that had some Cobalt-60 accidentally mixed in. The affected products were found to emit low levels of radiation."

                              "The issue was discovered by Customs and Border Protection agents during a routine import screening of one of the containers. That container was held at the port and never reached Petco. The second container had previously cleared Customs and reached Petco’s distribution network."

                              I believe Cobolt-60 is used for medical purposes, and is stored in stainless containers (or even sealed capsules). If steel recyclers are careless or dishonest, this steel can be incorporated in larger batches of recycled steel.

                              I suspect US Customs is scanning containers for radioactivity on the behest of Homeland Security (e.g. dirty bomb material), rather than as a consumer safety measure.

                            3. I hear similar concerns from people shopping for a new car.

                              Let's set aside conspiracy theories and error'net crack pots. With Japanese concern for health and safety and their long standing attention to detail and high quality manufacturing, do you really think they would ship a radioactive consumer product?

                              Now add US Custom screening to the mix. You are more likely to get a radioactive product from China/Taiwan than Japan. This has in fact happened in the case of watch band link pins that were forged with some radioactive surplus metal in a large melt.

                              6 Replies
                              1. re: Sid Post

                                i hear what you're saying, but don't overestimate the japanese concern for health and safety. it's kind of both true and not true. do some research on the government coverups and minimal exclusion zones around the spill. i lived in the area for several years; trust me when i say there is a lack of transparency, a lot of outright obfuscation and lies, and a significant risk around fukushima.

                                that said i doubt it impacts knives. :-)

                                1. re: chartreauxx

                                  If you look back at our own history, we probably did just as much cover up than the Japanese did, like the "American Nuclear Guinea Pigs : Three Decades of Radiation Experiments on U.S. Citizens"

                                  1. re: Chemicalkinetics

                                    TMI was really much worse than people thought.
                                    Government scrambled the research for years.

                                    1. re: Chowrin

                                      At least TMI is an accident. There were actually US Government programs which intentionally nuclear exposure to US citizen for military testing purpose.

                                      Just google "American Nuclear Guinea Pigs"

                                    2. re: Chemicalkinetics

                                      Someone got in trouble in PA for putting a Forestry Camp (4kids) in a Radiation Zone up in Quehanna

                                      1. re: Chemicalkinetics

                                        oh, TOTALLY!!! it was living in japan and seeing that kind of stuff as an "outsider" that opened my eyes to the fact that it happens in every. single. country. on earth - including my own :-)

                                        we lie about big pharma, factory farming, and a ton of other things, too...

                                  2. 1. Pretty much everything you use and eat is radioactive.

                                    2. So, as a matter of fact, are you.

                                    3. We're all going to die. Guaranteed.

                                    4. Give me another beer.

                                    1. So for all intents and purposes, its plausible, tho not likely, that products coming from "Asia" can be tainted. And we can try to tell ourselves "No! Impossible!" but the reality is we'll never know for sure. And yes, I don't put it past the Japanese govt to spin and minimize-if for no other reason than to not create panic. What I've read to date is nothing short of globally catastrophic.
                                      But the Shuns are on sale at Marcy's!!!

                                      11 Replies
                                      1. re: Moneemaniac

                                        I unfortunately am close enough to a cancer patient currently receiving proton therapy for the tumor. They use brass plates (big, lunking things 10" in diameter and a solid 2" thick) precision-bored to the exact shape of the tumor to focus the proton beam.

                                        These brass plates are somewhat radioactive after the approximately 30 treatments, so the center stores the plates until the radioactivity half-life is spent before sending the plates to be melted down and recycled.

                                        It takes all of six weeks for the plates to be clean enough to send out for recycling.

                                        Brass is considerable softer (and thus more absorbant...) than knife-quality steel (carbon or stainless).

                                        That brass takes a 6-week pounding (during the course of treatment) from a direct hit from a proton beam.

                                        The radiation is considered safe for public contact six weeks after the patient has gone home.

                                        A knife contacts food for a few seconds at a time.


                                        There's a shitload of other stuff in my kitchen that would keep me awake if I allowed myself to think about it -- and a radioactive knife doesn't even show up on the radar.

                                        1. re: sunshine842

                                          sunshine482: i took medical physics from john gofman
                                          i normally don't city wikipedia, but since i knew the man and his work PERSONALLY and the wikipedia material accurately reflects it,

                                          <<Dr. Gofman established the Biomedical Research Division for the Lawrence Livermore National Laboratory in 1963. In 1964, he raised questions about a lack of data on low-level radiation and also proposed a wide-ranging study of exposure in medicine and the workplace at a symposium for nuclear scientists and engineers. This helped start a national inquiry into the safety of atomic power. With his colleague Dr. Arthur R. Tamplin, Dr. Gofman then looked at health studies of the survivors of Hiroshima and Nagasaki, as well as other epidemiological studies, and conducted research on radiation’s influences on human chromosomes. The two scientists suggested that federal safety guidelines for low-level exposures be reduced by 90 percent in 1969. The Atomic Energy Commission contested the findings, and "the furor made Dr. Gofman a reluctant figurehead of the anti-nuclear movement" according to The New York Times.[3]>>

                                          sunshine842, your knowledge about radioactivity is extremely limited.

                                          1. re: westsidegal

                                            I never even flickered the claim of being a radioactive expert.

                                            My post, however, contains information relayed to me within the last 30 days by multiple employees of the center which I reference...all of whom, we'll (ahem) assume have received more training and education about radioactivity than you and I have, combined.

                                            Nuclear warfare and nuclear medicine aren't the same thing.

                                            1. re: sunshine842

                                              nMRIs are perfectly safe (non radiative analysis). Other than that, I wouldn't assume that a med tech knows much of anything other than how to push buttons.

                                              1. re: Chowrin

                                                Well, the term "radiation" is just different for different people. If we use the physic term for radiative, then any electromagnetic frequency is a radiation, ranging from your FM/AM radio frequency, to your toast oven IR, to our visible wavelength, to UV, to X-ray....etc.

                                                In this context, nMRI or NMR is a radiation, and so do many things.

                                                1. re: Chemicalkinetics

                                                  Many things are radioactive. Light - as Chemicalkinetics mentions - is a form of radiation.

                                                  The type of radiation that is most concerning to our health is ionizing radiation--which is radiation with enough energy to rearrange electrons.

                                                  Many people seem to either be unaware or forget that radiation is a natural part of our environment. We are all radioactive to some degree.

                                                  1. re: Cynic2701

                                                    "The type of radiation that is most concerning to our health is ionizing radiation .."

                                                    Exactly. I'm not going to blame skin cancer on my Cell Phone. ;-)

                                                  2. re: Chemicalkinetics

                                                    nuclear magnetic resonance isn't radiative. Are you using radio frequencies to detect it? sure. But, I mean, if you're going to worry about radio, then you'd better hide!

                                                    1. re: Chowrin

                                                      <Are you using radio frequencies to detect it? sure>


                                                      <nuclear magnetic resonance isn't radiative.>

                                                      You have to excite the magnetic resonance frequency. There is radiation -- well, based on the physics definition anyway.

                                                      Quote: "Nuclear magnetic resonance, NMR, is a physical phenomenon of resonance transition between magnetic energy levels, happening when atomic nuclei are immersed in an external magnetic field and applied an electromagnetic radiation with specific frequency. "


                                                      "Note that this electromagnetic radiation falls in the radio and television broadcast spectrum. Nmr spectroscopy is therefore the energetically mildest probe used to examine the structure of molecules. "


                                                      I am not saying that we need to worry about radio or NMR. I was just saying that it is radiation afterall, and people should not have knee jerking reaction when they hear/read the word "radiation". Visible light is also radiation. We don't start to scream and run when the sun rises everyday.

                                                  3. re: Chowrin

                                                    who said it was just techs? I didn't, because they weren't.

                                                    who said anything about MRI? Not I, again. (if you'll glance back up there, you'll see I specifically said proton therapy...which is most definitely radioactive.)

                                            2. re: Moneemaniac

                                              <its plausible,>

                                              I suppose everything is possible. I was just about to comment the same thing sunshine842 has. A knife contact on food is very short (a second or less). We are not talking about a cooking vessel where the food can sit in there for hours. It is also possible that the US government is still experimenting us for radiation.

                                              "The report found that between 1945 and 1947 eighteen hospital patients were injected with plutonium. The doctors selected patients likely to die in the near future. Despite the doctors' prognoses, several lived for decades after."

                                              One thing I do know for certain though is that my government is recording this.

                                            3. I'd be more worried about radioactive granite countertops.

                                              1. See the glass half full, Grasshopper! Maybe the radioactivity will kill bacteria in the food you're preparing.

                                                1. Jeez Louise!!! Sorta sorry I started all this.

                                                  1. Don't eat Brazil Nuts.