A claim: radioactivity can be reduced by bacteria. See this link:
Bacterial transmutation of radioactive cesium
Radioactive Cs-137 is mostly responsible for meltdowns of spent reactor fuel.
Ludwik Kowalski (see Wikipedia)
.
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A claim: radioactivity can be reduced by bacteria. See this link:
Bacterial transmutation of radioactive cesium
Radioactive Cs-137 is mostly responsible for meltdowns of spent reactor fuel.
Ludwik Kowalski (see Wikipedia)
.
So what are the details of the claim? what bacteria? how long a time for breakdown? As a matter of fact, as Cs-137 is an atom, what exactly do you mean by "Breakdown"?
I don't believe bacteria can accomplish anything other than chemical transformations (re-arranging the atoms in molecules). I don't believe they're capable of reaching into atomic nuclei and accelerating radioactive decay.
The data claimed by the link certainly say something else. My initial reaction is that the results reported are most likely due to fraud or incompetence. Of the two, my preference is for fraud -- some huckster wants to be paid for his magic bacteria to clean up nuclear waste. Until a couple of independent researchers can verify these results -- and given their outlandish nature, I don't expect a stampede of researchers eager to attempt it -- I will risk an egg-faced future and say simply "preposterous."
Ludwik, you're a physicist. I'm surprised you would post such a thing.
I am also very skeptical about bacterial transmutations. At least two independent replications would be needed to change my expectation. But I believe that in science theories guide while experiments decide.
Ludwik Kowaalski (see Wikipedia)
.
I think the bacteria positioned the radioative material in such a way that the radioactive decay (from the radioactive material) ricocheted with other radioactive nucleus more often and thus increase the probability of transmutation. Perhaps the bacteria had condensed/compressed Cesium-137 in somekind of pocket/vacuol (which was shielded with heavy nuclei: CaCO3 or D2O molecule) which reflect the radioactive decay (in this case: proton) back toward the radioactive material: thus increase the chance of hitting the radioactive nucleus and destabilizing it: thus increasing the decay probability.
-I think this is true because the paper said the transmutation rate increase/decrease if you use different kind of substance (eg: add CaCO3, or grow bacteria in D2O instead of H20).
did they specify the type of bacteria used? It still does not seem to be a viable way to change the natural half-life of the Cs
Read the article - they measured radioacitvity in the supernatant, offering a "control" to account for loss due to precipitation by testing an uninoculated control. Lots of microbes and microbial polymers will bind and precipitate cesium ion. Tjhere's no indication this was peer reviewed or even published.
HTML] The key microbial processes in the removal of toxic metals and radionuclides from the environment[HTML] from omfi.huLG Gazsó - CENTRAL EUROPEAN JOURNAL OF …, 2001 - omfi.hu
... Metals contained within these wastes include the fission product strontium and caesium. ... to remove
toxic metals and radionuclides, eg, ion exchange and precipitation, lack specificity ... Microbial
transformation of toxic metals and radionuclides may affect their solubility, mobility ...
Cited by 15 - Related articles - Cached - BL Direct - All 3 versions
moving ions around does not change the instability of the ion itself, thus there really shouldn't be a change in the decay rate of the Cs no matter what the bacteria are doing with it if anything.
Bacteria can reduce radioactive uranium. Published recently in a top interdisciplinary journal, here's a summary from Scientific American:
Electrified Bacterial Filaments Remove Uranium from Groundwater: Scientific American
That's great, but Paleo's last post applies.
I agree, just thought the article might increase plausibility. Also, did anyone else spot this in the link?
"The possible reaction of Cs 137 isotope utilization is Cs 137 + p1 [proton] = Ba 138 (stable) + DE. The result of this reaction is the creation of stable Ba 138 isotope. This reaction is energy favourable (DE = 5.58 MeV is positive)."
They never stated that the bacteria increased decay of the cesium isotope, but reduced radioactivity by stabilising it in an energy-favourable reaction, using protons that would be freely available in a slightly acidic environment. I'm not familiar with the cesium atom and it's radioactive potency in a biological system, nor am I even really familiar with radioactivity. But bacteria have evolved extremely diverse metabolic pathways to obtain energy in every habitable environment, I don't think I'd be entirely surprised that a bacterium was utilising the above reaction if it was possible. I'd like to see the work presented in a journal after being reviewed by world experts in the field, personally, I don't have the knowledge to claim if it's possible or not.
The problem is that the half life of a material is represented by a probability curve, i.e. after a certain time about half of the atoms would have decayed and after a second interval, half of the remaining atoms would have decayed, etc. The thing is, there is no known way to increase the rate of decay short of bombarding the atom with particles, which a bacteria can't do.
I understand, thanks. The authors were proposing that the bacteria catalyse the reaction of Cs 137 and a proton, producing a more stable atom that would decay much slower, making it appear that the decay rate has slowed. Is that possible?
Edit: Sorry, what I meant to say was that the conversion of Cs 137 to the more stable Ba 138 would decrease decay rate. But if you were to measure radiation over time, you would see less radiation than the control, and could assume that the bacteria were increasing the rate of decay (although, surely this would require a greater rate of decay than the control before it eventually "burns out", that's not what their data show). This is what I feel several people here have incorrectly concluded. If the data is indeed correct/ not falsified, the proposed hypothesis, in my opinion, is that the bacteria aren't increasing the rate of decay at all, just stablising the atom (as in the equation I quoted in my previous post) and perhaps utilising the energy from the reaction in some way.
Last edited by spoonman; September 6th, 2011 at 10:16 AM.
So they are suggesting the bacteria are converting the element Cs into the element Ba? I know manipulation for elements by bacteria is common (eg gold precipitation by bacteria), but I don't know if I have heard of bacteria with the ability to change an atom from one element to another!
Last edited by Paleoichneum; September 6th, 2011 at 12:08 PM. Reason: spelling
? Cold fusion, that would be. I'll believe it when I see a detailed mechanism and extraordinary evidence.The authors were proposing that the bacteria catalyse the reaction of Cs 137 and a proton,
From my understanding, the reaction is energy favourable and would occur spontaneously. The data suggest a biological catalyst increases the rate of the reaction. I too would like to see the isolation and subsequent characterisation of the catalyst in vitro, as well as publication of the data before I accepted it. I felt people had mis-interpreted the data which is why I stated my views. Please correct my interpretation if it is incorrect.
I don't believe bacteria (or any catalyst they might employ) can shoot protons through an electron cloud to speed fusion. The results mentioned earlier for uranium involved chemical reactions which made compounds containing uranium which were less soluble than those which existed previously. The compounds containing the uranium thus precipitated out of solution, making the uranium easier to remove. The cesium claimants make a point of saying that precipitation is not observed in their experiments, so that's not the mechanism they're claiming to employ.
But they can acidify their environment. Doesn't the reaction, Cs 137 + p1 [proton] = Ba 138 (stable), which is energy favourable, show that a simple increase in the concentration of hydrogen ions would increase the rate of reaction? The experimenters should have recorded pH levels over time, without these data, it is impossible to say that this is what was happening.
I agree that the mechanism reported in the uranium paper is distinctively different.
No due to the fact that the half-life is unaffected by the environment the material is in. As stated before its a probability curve that describes how long it takes half the unstable isotopes to loos the extra protons.
The claim is that the bacteria reduced the radioactivity of the test material faster then natural decay rates. The only way of accomplishing this is to convert to the non-radioactive barium faster the natural day can, as I understand things. Merely rearranging the Cs atoms would not change the amount of radioactivity, you have to add (I stand corrected) a proton.
The reaction is one that would occur spontaneously, a greater concentration of hydrogen ions in the environment would increase the rate of reaction, thereby converting the unstable cesium atoms to stable barium, and in turn, reducing the radioactivity. If the bacteria were acidifying the environment, this is what would be observed. Of course, the pH wasn't recorded and the experimenters didn't speculate that this was the reason for the reduction in radioactivity so it's impossible to say. Although, I think it's theoretically sound, and as I said previously, I'd like to see the results presented in a peer-reviewed journal after being scrutinised by experts in the field.
The thing is the paper seems to be indicating a change in the decay rate of the Cs (30 years) is being sped up by 29 times. The thing is the halflife of an isotope is not changeable, this something seems to be happening that is going against the current Chemistry and physics laws.
The half-life isn't changing though, the cesium atoms aren't decaying, they're being converted, through the addition of a proton, to a more stable atom that has a greater half-life than cesium, thereby slowing the decay rate. Hypothetically speaking, if you could decrease the half-time you would see a much greater increase in radioactivity against the control before it all decayed, this isn't what's shown in the data; the decay rate isn't increasing, it's decreasing.
If they are no longer Cs then they are decaying, any change from one element to another through addition/subtraction of nucleus particles has to follow the laws as they are known.
That bacteria can bind a radioactive element and remove it from the environment I will by but that bacteria can change one element to another by a chemical recation is a very much differnt claim.You don't change one element into another by putting them in an acid soup. That would just get some sort of cesium salt, not barium. The thing it is NOT is theoreticly sound.September 11th, 2011, 08:20 PM
The reaction is one that would occur spontaneously, a greater concentration of hydrogen ions in the environment would increase the rate of reaction, thereby converting the unstable cesium atoms to stable barium, and in turn, reducing the radioactivity. If the bacteria were acidifying the environment, this is what would be observed. Of course, the pH wasn't recorded and the experimenters didn't speculate that this was the reason for the reduction in radioactivity so it's impossible to say. Although, I think it's theoretically sound, and as I said previously, I'd like to see the results presented in a peer-reviewed journal after being scrutinised by experts in the field.
The reaction I have been defending: "Cs 137 + p1 [proton] = Ba 138 (stable) with a change in E of +5.58 MeV" purports that energy is emitted in the changing of this one particular element to the other. Admittedly, I found a paucity of references to such an equation in a quick literature search, if it has been falsified, my defence of the theory was completely pointless as it is ultimately incorrect. Nevertheless, if the data is correct; Sealeaf, "bacterium bind a radioactive element and remove it from the environment", here's a potential mechanism in this recent paper: Effects of low molecular weight organic aci... [Appl Radiat Isot. 2011] - PubMed - NCBI. The authors show that low MW organic acids can aid in the precipitation of radioactive cesium from soil in an environment. There is no reported reaction between the LMWOAs and the Cs 137 atoms.
I strongly suspect that the effect that had originally been reported on was some sort of chemical reaction, mediated by the bacteria, that combined Cesium with some other elements the make a compound, perhaps a organic chemical that took the Cesium out of the solution and rendered it safe. But it was safe, not because it was no longer radio active, but because it was no longer chemically active.
Radioactive isotopes are dangerous principlaly because the human metabolism absorbs them into our tissues just like their non radioactive counterparts. Most radio isotopes decay by emitting an alpha particle. Alpha particles have very low penetrating power. As long as the source of them is outside our bodies they are unlikely to harm us.
A radioactive isotope that is tightly bound in a compound that humans can't digest has been rendered quite "safe". It is still radio active, but its out there, not in us.
Found this on wiki: Caesium-137 reacts with water producing a water-soluble compound (caesium hydroxide), and the biological behavior of caesium is similar to that of potassium and rubidium.
In a bacterial culture, the Cs would be CsOH, I wonder if this would diffuse into bacterial cells. If it did, would you still be able to detect radiation? If you couldn't detect radiation, then a simple diffusion into living cells would be enough to show a reduction in radiation/decay against a control with no bacteria.
Caesium hydroxide is an extrememly potant base, I don't think your average run of the mill bacteria would be able to survive this. Hydroxyl groups tend to be hydrophillic and don't tend to move across membranes. Also the chemical (bonds) doesn't tend to affect the physical (nucleus). Cs decays to barium by means of a beta particle, even if the culture were dense enough to stop most of these escaping, barium rapidly decomposes by gamma ray...
Thanks, I'm completely unfamiliar with the compound. Just out of interest, why can't hydrophilic compounds diffuse across the phospholipid membrane, is it because of the hydrophobic centre? I figure that if water can diffuse through it (osmosis), then anything that's hydrophilic will also be able to.
Bacteria can carry out chemical reactions. To convert radioactive Caesium to a non radioactive material is a nuclear reaction. This cannot be done by bacteria. Adding a protein to the nucleus cannot be done chemically, but only by high energy bombardment, which is out of the capability of bacteria.
Like an earlier poster, I suspect fraud.
I'm in agreement, skeptic, while the authors didn't claim that they could reduce the half-time of cesium (as several people have highlighted as impossible), what they did claim appeared to be equally impossible.
I found this on Google Books:
I don't know enough to speculate whether there might be a "proton capture cross section" which differs from the neutron capture cross section, but Wiles goes on to list normal nuclear reactors, special high-flux nuclear reactors, and accelerator-generated neutron beams as the practical options for transmutation. These all involve high-energy particles, not merely a particle-rich environment. I still don't believe chemical processes can accomplish the feat.The normal half-life of 137Cs is 30 years, while that of 138Cs is only 32 minutes. Barium-138 is stable and harmless. Clearly, then, the transmutation process would seem to have some advantages in eliminating 137Cs, if it would work.
The rates at which these reactions proceed depend on the number of nuclei present, the neutron capture cross section, and the neutron flux. [...] [B]ecause of its very small neutron capture cross section, the transmutation of 137Cs proceeds only very slowly, and has little measurable effect on the normal half-life of Cesium-137.
- The Chemistry of Nuclear Fuel Waste Disposal by Donald R. Wiles
This is still talking about precipitation - binding the radioactive element in a molecule which is easier to remove from solution, not changing the radioactive element into a different element (or isotope). That's not what the original post described; in fact, the article linked made a point of excluding it.
Thanks, that information seems to firmly debunk the theory.
You're quite right, the reason I included this was that the authors of the original article Bacterial transmutation of radioactive cesium stated:
"These results can give the answer to the question of the reasons of abnormal accelerated decrease of environmental radioactivity in some isolated areas inside Chernobyl NPS accident zone and after bombing of Hiroshima and Nagasaki with initial high level of radiation pollution."
The article that I cited, and you quoted, provides an alternative explanation for this phenomenon. Rather than bacterial activity reducing radioactivity, perhaps some areas are richer in habitation and the increased LMWOAs in the environment increase the precipitation of radioactive cesium from that area.
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