BRAWM Team: What Are The Results Of The Plutonium Analysis

A few weeks ago, Mark said that plutonium data was being analyzed
and a final report was pending. I don't recall seeing the results.
Has that analysis been completed? And if so, can you please post
the results?


We've taken some data over
Submitted by bandstra on Wed, 2011-04-20 02:26.
We've taken some data over the last few days with an alpha spectrometer and are currently analyzing the data. We should have a final report on that later in the week.

By the way, we are not seeing any clear signs of plutonium. The analysis is to set an upper limit so we can compare to the limits of other tests, such as the EPA data.

Mark [BRAWM Team Member]


Report has been posted

7/31 (9:15pm): We have finished the analysis of the alpha particle spectrum from an air filter collected on April 16–19. We did not detect any Uranium, Plutonium, or Americium-241, and our calculated detection limits indicate safe levels. Our limits are much higher than the limits set by the EPA in their testing for Uranium and Plutonium. If you would like to skip directly to our limits, please click here.

Thanks for your patience with us as we ventured into alpha spectroscopy, which is very different from our main expertise in gamma-ray spectroscopy.

I have opened up a new thread for this topic:

Mark [BRAWM Team Member]

Update (7/14)

Apologies for the lack of updates on this. We still have the sample in the detector and are saving spectra weekly while I try to do the best analysis of the data. The problem still is that the detector response is very complicated because alpha particles are not as well-behaved as gamma rays. I am working on getting an appropriate detector response, and then I will be able to properly subtract the natural alpha background. There will still be a large uncertainty on the limit that we will set for the uranium and plutonium isotopes due to geometry, so it will probably not be any better than the EPA's limits. One of the papers I have read to understand the alpha response is this one:
Minimum Detectable Activity Concentration in Direct Alpha Spectrometry From Outdoor Air Samples: Continuous Monitoring Versus Separate Sampling and Counting Pöllänen, R; Siiskonen, T Abstract Rapid method for identifying the presence of alpha particle emitting radionuclides in outdoor air is of paramount importance should a nuclear or radiological incident occur. Minimum detectable activity concentrations of 238U, 234U, 239Pu, and 238Pu in outdoor air are calculated for two direct alpha spectrometry methods: continuous air monitoring is compared with separate sampling and subsequent alpha particle counting in a vacuum chamber. The radon progeny activity concentration typical for outdoor air and the effects for the alpha particle spectra caused by the properties of the filter and the aerosol particles are taken into account using measurements and Monte Carlo simulations. Continuous air monitoring is a faster method for identifying the presence of (trans)uranium elements when their activity concentration is considerably higher than the typical detection limit. Separate sampling and counting in a vacuum chamber is a more sensitive method when concentrations are close to the detection limit and when the duration of the sampling-counting cycle is greater than approximately 2 h. The method may serve as a tool for rapid field measurements.
Mark [BRAWM Team Member]

Explaination of data region 9 and 10 plutonium data Bltg

Mark I am sure u have Explained this away too.but I find that these traces being detected in pacific islands and west coast only is interesting . I realize the csu is in play but it doesn't mean the epa didn't detect it does it?The dates and data seem to me to show some minuscule plutonium has arrived post Fukushima is your test for plutonium indicating tiny traces below your mda.since I am no expert and since the EPA has changed there measurements from Acim/3 to pci/m 3 at some makes comparison hard for me to compare pre fuku to post fuku data.

Description: The Combined Standard Uncertainty (CSU) is the estimated standard deviation of the result. The CSU can be used to estimate the "confidence interval" around the amount. Thus, if y is the "best estimate" of measured radioactivity, the 95% confidence interval around y ranges from about y-(2xCSU) to y+(2xCSU). For Strontium-90 in milk during the period of 1960 through July 1978, the uncertainties were +/- 2 pCi/L (two sigma) for Sr-90 concentrations less than 20 pCi/L, and 10% of the concentration for Sr-90 concentrations greater than 20 pCi/L. Sample specific uncertainties are available for data beginning


Aerosols can travel far why have all i read every nuclear expert been saying plutonium is to heavy to go far blah blah blah .tell me there is no way it could travel here in aerosol form show me science that says this isn't possible .

Interesting that the above

Interesting that the above quote refers to the need for "rapid sampling", which obviously is either not taking place or the results are not being reported. Since the beginning of the Fukushima disaster and during the ongoing discourse here on this very appreciated forum, I have started to ask myself "How is it that incredibly intelligent scientists and engineers are able to split the atom, create man-made isotopes, nuclear reactors and bombs... but they are UNABLE to MEASURE the RESULTS and IMPACTS of their creations, not to mention their utter failure to correctly predict and later treat the horrible adverse health effects on humans?" I FAIL to understand why it appears scientifically impossible to reliably measure these develish and crucial alpha emitters in a reasonable time frame and have come to the sad conclusion that the reason must be political and economic rather than scientific. Thank you for your ongoing work and patience, BRAWM, under the circumstances. I can only try to imagine the likely limitations not only of your lab, but also of your ability to publicly report your results.

I think we understand it

I think we understand it perfectly well. And there's nothing we can do about it.

Ain't 'that' the truth...

"I think we understand it perfectly well. And there's nothing we can do about it."

Ain't 'that' the truth...

yeah, I agree. There is

yeah, I agree. There is nothing we can do about it.

We (BRAWM) cannot do everything...

(1) We do not do alpha testing in our regular research, nor was that ever our point in BRAWM. We have been trying to do this alpha test because we had some equipment available and people asked if we could, but it turns out to be difficult. One reason it is hard is because we (BRAWM) never do these kinds of measurements.

Other people do alpha testing routinely and have the right equipment, such as the EPA. They have done tests and found no plutonium to good limits, and uranium consistent with natural abundances. Alpha detection is not "scientifically impossible" in general; it is just difficult for us (BRAWM).

(2) I am reading that article because it talks about the modeling needed to understand the "effects for the alpha particle spectra caused by the properties of the filter and the aerosol particles." This is relevant to our test because the particles are aerosols on a filter. The specific application they are talking about is rapid detection (<2 hours). That was not our intention with our alpha test, nor is it required in general that the testing be rapid.

(3) The limitations on our public reporting are not political at all. We have complete freedom to do whatever we want, within the constraints of time and manpower.

Mark [BRAWM Team Member]

Thanks, Mark, for these

Thanks, Mark, for these explanations. It is good to better understand your testing situation, and I have great respect for your ongoing efforts and motivation to delve into "new" territory with the alpha measurements. Thank you! Isabel

You are the only academics I

You are the only academics I have ever heard of with that amount of freedom, and I've been in the sciences a while.

a dumb question maybe I don't know made me curios

Mark does this come into play when trying to measure radiation particles?

"Any attempt to measure precisely the velocity of a subatomic particle, such as an electron, will knock it about in an unpredictable way, so that a simultaneous measurement of its position has no validity. This result has nothing to do with inadequacies in the measuring instruments, the technique, or the observer; it arises out of the intimate connection in nature between particles and waves in the realm of subatomic dimensions.

Every particle has a wave associated with it; each particle actually exhibits wavelike behavior. The particle is most likely to be found in those places where the undulations of the wave are greatest, or most intense. The more intense the undulations of the associated wave become, however, the more ill defined becomes the wavelength, which in turn determines the momentum of the particle. So a strictly localized wave has an indeterminate wavelength; its associated particle, while having a definite position, has no certain velocity. A particle wave having a well-defined wavelength, on the other hand, is spread out; the associated particle, while having a rather precise velocity, may be almost anywhere. A quite accurate measurement of one observable involves a relatively large uncertainty in the measurement of the other."

Not important at a practical level

Hi Tdm,

What you have quoted there is the famous Heisenberg Uncertainty Principle. In plain language, it means that at the atomic and nuclear scale, particles like electrons and protons don't act like "billiard balls." They are more "fuzzy," but in a non-intuitive way: they can exhibit wave interference with each other. This makes the physics much stranger than the "billiard ball" model, but it actually describes a ton of weird effects that people started noticing in the late 19th and early 20th centuries.

For the most part, the effects of the Principle are not important in radiation detection. We do not need to use it directly when we make the measurements that we make in BRAWM, since the interactions of electrons and gamma rays and alpha particles can be described for the most part without it.

At the same time, that Principle does underlie all of modern physics. It governs the laws of how subatomic particles interact, but its effects are just not important in the particular type of radiation detection that we are doing.

Mark [BRAWM Team Member]


Bumping again

Plutonium detection will not come from Nuclear Industry PR

Once plutonium is detected it will mean that the NRC and the Nuclear Industry were wrong about 100% of everything they stated safety-wise and radionuclide distribution range.

Right now if one could encapsulate the entire Nuclear Industry into one person and sit that person down in a courtroom for questioning and ask:

"Isn't it true that you were wrong about everything you told us about backup system contingencies and safety methods and range of distribution of radionuclides?"

That witness on the stand would currently be able to answer:

"Well, ACTUALLY, no one ever detected plutonium, so therefore, we weren't wrong about 'everything'. You have to understand the science counselor, you see...this public misunderstanding of the science behind this event is much like an airplane flight...."

Any Update On This?

Hi Mark and team,

Any update on this?


I too am very interested in the plutonium update.

BRAWM - Can we please get an

BRAWM - Can we please get an update on this?

please give us update

please give us update

Its been over two months

Its been over two months now, surely BRAWM has made some progress on this? Why are u not responding or updating us on your analysis? Mark you told us we would have a final report in a week! Will you please post the results?

BUMP.. Hows the progress

BUMP.. Hows the progress going?

March 30 Sydney morning herald article


According to plant operator Tokyo Electric Power Company (TEPCO), soil at five sites at the Fukushima plant was found to have plutonium. At least two of these sites had isotopes where there was a "high possibility" of a connection to the accident. But no sample was of a level of contamination that was hazardous for health, it said. France's Nuclear Safety Authority (ASN) described the data as being in the same category as "background levels" that are a legacy of atmospheric nuclear bomb tests. Around four tonnes of plutonium were released into the global environment before atmospheric testing ended.


This is unclear. Experts at France's Nuclear Safety Authority (ASN) say it could have come from the No. 3 reactor, which uses mixed oxide, or MOX, which comprises plutonium and uranium that has been extracted from spent nuclear fuel and reprocessed. Alternatively, it could have come as a fissile byproduct from burning uranium in the No. 1 and 2 reactors.
Bump yes Its out facts suck.tepco can't change story on this.

Update 5/26

As I've already mentioned, the data analysis is turning out to be difficult. Our method doesn't seem to be entirely invalid, but it is overly complicated and not very sensitive. We will try to put out a limit soon and show some of the data, but don't expect miracles please ;)

If it is any consolation, we are trying to figure out a limit on Pu-239, U-235, U-234, and U-238. We definitely don't see a clear signature of them. But as I said, our method is not very sensitive either... not near the EPA sensitivity for sure.

We will obviously keep our air sample (taken 4/16-19), and we are looking into ways to do alpha spectroscopy with it properly. It would involve some chemistry and equipment that we do not have.

Mark [BRAWM Team Member]


Plutonium How far could it travel?

Richard Lahey, who was General Electric's head of safety research for boiling water reactors when the company installed them at Fukushima, said that radioactive material that has leached into the land is likely to bind to the soil and stay there, while any plutonium released into the sea would become diluted and disperse.

Dear Brawn team, your work

Dear Brawn team,

your work is so much appreciated, as is the continued running of and dialogue on this forum. Thank you! (I just hope you don't have to check with the EPA or other agencies before you can post your Plutonium results).
Thanks so much again!

Thanks for the update, Mark

No miracles expected :-) Just please keep up the great work.

please release the test

please release the test results





BRAWM - can we get an update

BRAWM - can we get an update on this??

Lack of info creates suspicion

After over a month of waiting, I'm sure a lot of folks are getting suspicious about the lack of results on plutonium. After all, the BRAWM team has turned around results pretty quickly on everything else. There have been some technical reasons given for the delay. But,after a month, one has to wonder. Especially when even the EPA is only took a week
to 10 days to report Pu results.

BRAWM is using a different

BRAWM is using a different process for their detection. It wouldn't surprise me if the testvis invalid because of how samples were obtained.


Now, for folks that tend to get suspicious, I think that would make them moreso, to suddenly say that the testing is invalid.

Get a life. That's how

Get a life. That's how science works. You try one approach and see if you get results, if not you try a different approach.

It's not like if there is Plutonium it will decay away. It got a 24,000 year halflife.

Even the BRAWM team freely admits that

They are constantly refining their process to increase sensitivity
and accuracy. Which is what you'd expect of good scientists. So,
maybe the way they obtained the samples would render them invalid.
I don't know what would cause that. But, it's not impossible. The only
issue is, if their collection technique was flawed, they won't get
a second chance to sample 4/19 air. It's not like the air mass from
a month ago is just sitting around waiting to be collected. It's moved
on. If it's just a matter of how they are analyzing the data on the
filters, then yes, they've got thousands of years to get it right.


That's a very informative and constructive reply, which makes total sense.

As opposed to the "get a life" a life reply - that poster needs to chill.

Get a life.

Get a life.



nervous in CA

Any news here BRAWM?

Alpha update 5/14

Just a quick update on this -- we're still taking data to get enough statistics in our alpha spectrum. We're also refining the analysis to interpret the data properly.

It appears that all of the short-lived radon progeny have died away except for Polonium-210, which has a 138 day half-life. Po-210 has an alpha line at 5.30 MeV, which is the only feature in the alpha spectrum at this point. This line happens to be close to the alpha lines of the following isotopes of interest:

U-238: 4.15 and 4.20 MeV
U-234: 4.72 and 4.77 MeV
U-235: 4.37 and 4.40 MeV
Pu-239: 5.14 and 5.16 MeV

So we need better statistics in order to tell if these nearby, much weaker lines are present at all in the spectrum, which is currently dominated by the strong alpha line of Po-210.

Mark [BRAWM Team Member]





Thanks, Mark

I hope you aren't saying we'll have to wait 138 days or more for the Po-210
to die away before we can know :-)



Read IAEA fact sheet on po210 that's breaking news if this came from Japan.this is a dangerous element according to iaea have u picked up po210 in most tests ?


Please read the above post, and read about Radon progenies. And read the IAEA document you just posted:
Because Po-210 is produced from the decay of radon-222 gas, it can be found in the atmosphere from which it is deposited on the earth´s surface. Although direct root uptake by plants is generally small, Po-210 can be deposited on broad-leaved vegetables. Deposition from the atmosphere on tobacco leaves results in elevated concentrations of Po-210 in tobacco smoke. There are tiny amounts of Po-210 in our bodies.
Mark [BRAWM Team Member]


So it's not from Japan correct it's naturally here?

210Po (in common with 238Pu) has the ability to become airborne with ease: if a sample is heated in air to 55 °C (131 °F), 50% of it is vaporized in 45 hours, even though the melting point of polonium is 254 °C (489 °F) and its boiling point is 962 °C (1763 °F).[13][14] More than one hypothesis exists for how polonium does this; one suggestion is that small clusters of polonium atoms are spalled off by the alpha decay.

Correct, naturally here.

Correct, naturally here.

Basically, radon gas comes from rocks and the soil (ultimately from naturally-occurring Uranium-238). It decays into various things over time, including Po-210. In our alpha experiment, we have seen other radioactive isotopes in the "decay chain," but Po-210 has the longest half-life of the alpha emitters.

Mark [BRAWM Team Member]

Not seeing it in spectrum o

Not seeing it in spectrum o gee.