The CODOH Revisionist Forum

In his 1994 paper, linked below, Markiewicz tells us:

We decided therefore to determine the cyanide ions using a method that does not induce the breakdown of the composed ferrum cyanide complex (this is the blue under discussion) .....carried out by Epstein's method.

https://codoh.com/media/files/downloads ... 94-ocr.pdf

Citing Joseph Epstein's paper: Epstein J., Estimation of Micro quantities of Cyanide, Analytical Chemistry
1947, Vol. 19, p. 272.

He then claims

Under present circumstances we established the lower limit of determinability of cyanide ions at a level of 3-4 μg CN- in 1 kg of the sample.

Germar Rudolf challenges this in his work "The Chemistry of Auschwitz", as follows:

The Polish scientist used the microdiffusion-chamber procedure, which does not permit the detection of iron-
cyanide compounds like Iron Blue. The Poles claim that the detection limit for other cyanides lies at a concentration of 3-4 μg per kg sample material, yet the paper they cite clearly gives 0.2 mg/L (200 μg/kg) as a detection limit for aqueous solutions. The samples of the second series were analyzed three times. For the resulting differences see Table 30.

Section 8.2.1

So, who is right?

Lets analyze the original 1947 Epstein paper as published, which was cited and utilized by Markiewicz in his 1994 paper. Link below, along with DOI code for those who wish to retain a copy in their archives:

https://pubs.acs.org/doi/abs/10.1021/ac60004a018
https://doi.org/10.1021/ac60004a018

Epstein starts with "exactly 10 micrograms of cyanide ion per milliliter of water"

This equates to 10 μg/ mL = 10mg/L = 10 ppm



From this stock solution, serial dilutions were prepared a range containing:

0.2 μg/mL = 0.2ppm
0.4 μg/mL = 0.4ppm
0.6 μg/mL = 0.6ppm
0.8 μg/mL = 0.8ppm
1.0 μg/mL = 1.0ppm
1.2 μg/mL = 1.2ppm

Minimum detectable threshold: The Epstein paper explicitly states that "as little as 0.2 micrograms of cyanide can be estimated with an accuracy of 99% ±4%."




This equates to 0.2 μg/mL = 0.2ppm, with the range given as lying at 0.2 - 1.2ppm

Conclusion: Rudolf clearly is right to call into question the detection limits as specified by Markiewicz.

So what gives?

The unfortunate answer is: we don't know. We do not know exactly what Markiewicz did to "enhance" the Epstein method to obtain a degree of sensitivity orders of magnitude greater than demonstrated by the known method, or whether he is simply misapplying, misreading, or misunderstanding the methodology and literature.

What we do know, is that whist somewhat similar, the Markiewicz methodology requires one further preparation step in the sample handling over the Epstein method, this is the step of liberating the cyanide from the carrier material via acidification (this step is not needed under the Epstein method, as the cyanide is already present in its simplest form in the solution, by design).

Per Markiewicz:

The sample under examination was placed in the internal part of the chamber and next acidified with 10% sulfuric acid solution and allowed to remain at room temperature (about 20°C) for 24 hrs. The separated hydrogen cyanide underwent a quantitative absorption by the lye solution present in the outer part of the chamber.

What we are left with is, not only does Markiewicz misstate (or overstate) his sensitivity, and not only does he fail to explain how this was achieved by orders of magnitude, he introduces additional complexity to the methodology requiring the samples to undergo extraction, with an unknown impact on the qualitative and quantitative results, along with the reliability of the chosen method.

Final note: Rudolf reproduces Markiewicz' 1994 results in section 8.3.2 and denotes readings below the established threshold as ND, and represents numerically those readings at or around the established threshold range (0.2ppm - 1.2ppm) using ppm notation, mg/kg

This is a quite technical point, but I think I follow those quotes from the paper and the math looks right. It's seems unlikely that Germar would have blundered here. Markiewicz in contrast I think had an obvious motive to fudge this: he didn't want to report a bunch of ND values since he knew that would look bad.

ConfusedJew tried to contest this, but he/GPT didn't make any substantial points that I can recall.

Archie wrote: ↑Fri Nov 14, 2025 8:42 am This is a quite technical point, but I think I follow those quotes from the paper and the math looks right. It's seems unlikely that Germar would have blundered here. Markiewicz in contrast I think had an obvious motive to fudge this: he didn't want to report a bunch of ND values since he knew that would look bad.

ConfusedJew tried to contest this, but he/GPT didn't make any substantial points that I can recall.

Agreed - the most charitable we can be to Markiewicz here is that his paper introduces enough unnecessary uncertainties to obfuscate the usefulness of these findings.

The obfuscations lay primarily in:

- Sample handling requiring one additional step over Epstein's method, which has an unknown impact on findings
- Reporting the detection limit in Xμg / kg format (solid per solid) whereby Epstein reported his in Xmg / L (solid per liquid)
- Not explaining these discrepancies and leaving it open to interpretation / imagination / speculation how accuracy was enhanced

Uncertainties of this caliber imo are indefensible, especially when relied upon so heavily and singularly by Orthodoxy, and held up as the gold standard. Were Rudolf to have made such missteps, like I said in a different thread, he would be laughed off the face of the planet, if not outright jailed for hatescience.

Archie wrote: ↑Fri Nov 14, 2025 8:42 am This is a quite technical point, but I think I follow those quotes from the paper and the math looks right. It's seems unlikely that Germar would have blundered here. Markiewicz in contrast I think had an obvious motive to fudge this: he didn't want to report a bunch of ND values since he knew that would look bad.

ConfusedJew tried to contest this, but he/GPT didn't make any substantial points that I can recall.

Markiewicz was a 'forensic expert' in courts in communist Poland. Testified in 3000 cases of which 5% were considered 'political'.... I couldn't find too many details on him. But one can find out what the role of 'expert witnesses' in Communist countries was... And what did guide them.

Hektor wrote: ↑Fri Nov 14, 2025 8:02 pm

Archie wrote: ↑Fri Nov 14, 2025 8:42 am This is a quite technical point, but I think I follow those quotes from the paper and the math looks right. It's seems unlikely that Germar would have blundered here. Markiewicz in contrast I think had an obvious motive to fudge this: he didn't want to report a bunch of ND values since he knew that would look bad.

ConfusedJew tried to contest this, but he/GPT didn't make any substantial points that I can recall.

Markiewicz was a 'forensic expert' in courts in communist Poland. Testified in 3000 cases of which 5% were considered 'political'.... I couldn't find too many details on him. But one can find out what the role of 'expert witnesses' in Communist countries was... And what did guide them.

There is a small bio of Jan Markiewicz on Codoh located here:

https://codoh.com/library/document/auth ... ewicz-jan/

I have seen some people attack the man and call him a fraud, or say he is unqualified because his PhD is not strictly in chemistry but rather the "natural sciences", which i think is a mistake, as it simply opens us into credentialism. Not saying you are doing this, but I have seen it.

Personally, I find it is more than adequate to "attack" Markiewicz' work rather than the man.

I've given some examples above for areas I feel are justified to attack Markiewicz on, and I will add one other which shockingly, Richard Green also repeats:

Rudolf would like to claim a pH of around 10 (a claim that we shall examine in further detail).
Note that if Rudolf were correct that the concentration of cyanide ions would be about 80% of
the initial HCN concentration. If the pH is 6-7 as measured by Markiewicz et al., it is about 1%
of the initial hydrogen cyanide concentration.

Green - Chemistry Is Not The Science

This is a shocking "mistake" for two PhDs to make, and once again Rudolf is absolutely correct here. Measuring the pH of concrete 30 years after it is poured tells us nothing about it's original pH. The analogy Rudolf gives us is; baking a pizza, letting it rest for 30 years and then measuring its temperature. Then claiming it was stone cold coming out of the oven (!)

Markiewicz is the original perpetrator of this "mistake", but Green is arguably more guilty for upholding this, many years after publication, and attempting to use it as a vector to attack Rudolf.

HansHill wrote: ↑Fri Nov 28, 2025 9:35 am

Hektor wrote: ↑Fri Nov 14, 2025 8:02 pm

Archie wrote: ↑Fri Nov 14, 2025 8:42 am This is a quite technical point, but I think I follow those quotes from the paper and the math looks right. It's seems unlikely that Germar would have blundered here. Markiewicz in contrast I think had an obvious motive to fudge this: he didn't want to report a bunch of ND values since he knew that would look bad.

ConfusedJew tried to contest this, but he/GPT didn't make any substantial points that I can recall.

Markiewicz was a 'forensic expert' in courts in communist Poland. Testified in 3000 cases of which 5% were considered 'political'.... I couldn't find too many details on him. But one can find out what the role of 'expert witnesses' in Communist countries was... And what did guide them.

There is a small bio of Jan Markiewicz on Codoh located here:

https://codoh.com/library/document/auth ... ewicz-jan/

I have seen some people attack the man and call him a fraud, or say he is unqualified because his PhD is not strictly in chemistry but rather the "natural sciences", which i think is a mistake, as it simply opens us into credentialism. Not saying you are doing this, but I have seen it.

I was more interested in his role during Communist rule in Poland, not his credentials. I assume that he was knowledgeable and capable with regards to chemistry. But that he was in a way a child of communist rule in Poland where the truth of a matter was decided by whether it supported the cause of the party or not. Except for the communist angle, one should not forget that poles tried to exploit the Holocaust narrative for their own gains.

And yes, the issue is whether the method and conclusions were warranted... And indeed it was the methods that appeared to be odd for a number of reasons.

HansHill wrote: ↑Fri Nov 28, 2025 9:35 am Personally, I find it is more than adequate to "attack" Markiewicz' work rather than the man.

I've given some examples above for areas I feel are justified to attack Markiewicz on, and I will add one other which shockingly, Richard Green also repeats:

Rudolf would like to claim a pH of around 10 (a claim that we shall examine in further detail).
Note that if Rudolf were correct that the concentration of cyanide ions would be about 80% of
the initial HCN concentration. If the pH is 6-7 as measured by Markiewicz et al., it is about 1%
of the initial hydrogen cyanide concentration.

Green - Chemistry Is Not The Science

This is a shocking "mistake" for two PhDs to make, and once again Rudolf is absolutely correct here. Measuring the pH of concrete 30 years after it is poured tells us nothing about it's original pH. The analogy Rudolf gives us is; baking a pizza, letting it rest for 30 years and then measuring its temperature. Then claiming it was stone cold coming out of the oven (!)

Markiewicz is the original perpetrator of this "mistake", but Green is arguably more guilty for upholding this, many years after publication, and attempting to use it as a vector to attack Rudolf.

Detection limits will be an issue, especially with the methods picked by the Cracow institute. Green should actually know better, but he decided to play along.... On the other hand he will admit that he doesn't really care about the forensic outcomes and the chemistry itself. It isn't relevant as they know that people were gassed there from 'witnesses' and of course from Jews privately missing relatives or friends, which however never were searched for like for people of other ethnicities after World War Two.

HansHill wrote: ↑Fri Nov 07, 2025 4:35 pm What we do know, is that whist somewhat similar, the Markiewicz methodology requires one further preparation step in the sample handling over the Epstein method, this is the step of liberating the cyanide from the carrier material via acidification (this step is not needed under the Epstein method, as the cyanide is already present in its simplest form in the solution, by design).

I was asking the AI about this (as I am admittedly out of my depth here) and it seems to agree the Epstein results would be a best case in highly controlled lab conditions but that practical tests would have more potential sources of error.

The Auschwitz procedure included additional steps:

• Cyanide had to be released from masonry.
• The released HCN had to diffuse through the Conway chamber.
• The HCN had to be trapped in alkali.
• Then the Epstein colorimetric assay was performed.

Each step can add losses, variability, and background noise.

So analytically you can think of it as:

Epstein detection limit → best-case sensitivity of the measurement chemistry

Auschwitz detection limit → sensitivity of the entire extraction + diffusion + measurement workflow

Those are often quite different.

And on sources of error,

Instrument noise

All analytical instruments produce some background signal, even when measuring a blank.
Random fluctuations can occasionally be interpreted as a tiny cyanide concentration.

*Reagent contamination

Trace impurities in water, acids, buffers, or other reagents can contribute a small signal.
Even high-purity chemicals are rarely perfectly free of contaminants.

*Laboratory contamination

Carryover from a previous sample containing cyanide.
Contaminated glassware, tubing, autosampler needles, or storage containers.

*Matrix interferences

Other compounds in the sample may produce a signal that partially overlaps with the cyanide measurement.
This is method-dependent and often more significant in complex matrices like soil, sediment, or biological tissue.

*Sample handling

Cross-contamination during collection, transport, subsampling, or preparation.

*Calibration uncertainty

Near the low end of the calibration curve, small uncertainties in the calibration can translate into apparent low-level concentrations.

How labs deal with this

Labs usually run:

Method blanks
Reagent blanks
Laboratory control samples
Duplicate samples

The Poles took three samples and the results, as reported, don't vary much. That would be one check for consistency, but not necessarily accuracy.

One overarching point with all this is that the results from Rudolf and Leuchter (and others) on total cyanide are highly robust and reproducible, and it's even confirmed by visual inspection. But these results of tens or hundreds of micrograms in contrast require considerable faith in a heavily incentivized Polish team whose results can't be checked.

Agreed. Another additional point worth mentioning when discussing Markiewicz and his detection limits, is that of carbonates as false positives in detecting cyanides. Rudolf explains this in TCOA section 8.2.2 as follows:

“One major challenge when analyzing masonry samples is the presence of
carbonate. Concrete, mortar and plaster samples that are several decades old
are all carbonated to a high degree, hence contain major quantities of car-
bonates mainly in the form of calcium carbonate (CaCO3). Meeussen/
Temminghof et al. (1989) have determined the false positives caused by car-
bonate in liquid solutions of 0.1 mg of cyanide per liter of water as listed in
Table 26”.

Eliminating and / or accounting for false positives is one of the main driving factors in acknowledging standard detection limits in the first place. We know that Markiewicz acknowledges the presence of calcium in his samples:

"It was determined, using the spectrographical method, that the main elements which made up the samples were: calcium, silicon, magnesium, aluminium and iron."

- page 4 (listed as page 20 on the Codoh PDF)

He also states:

"In this case the CN⁻ content in mortar... was for the most part lower in the wetted materials than in the dry ones....It seems that here a tendency is revealed towards the competitive action of carbon dioxide, which dissolves in water."

- page 9 (listed as page 25 on the Codoh PDF)

This means Markiewicz i) acknowledges that calium is a primary element in his samples, and ii) he recognized that CO₂ (which forms carbonate in water) interferes with cyanide binding and measurement (!)

However, with all of the above in mind he does not apply this knowledge to his sampling methodology. Nowhere in the Markiewicz paper does he discuss carbonate removal, nor run spiked recovery experiments on his actual (and self-acknowledged) carbonated samples. Finally he fails to make any mention of controlling for false positives at all. On the topic of replicability he does say:

“Each sample of materials examined was analysed three
times. If the result obtained was positive, it was verified by repeating
the analysis. Having applied this method for many years, we have op-
portunities to find its high sensitivity, specificity and precision.”

- page 5 / 21

This tells us nothing about the control of false positives, and as you rightly say above, supports only the result (not whether the result is cyanide or carbonate!)

Rudolf in contrast, repeated his test on four of his samples in a separate laboratory using a different method. Some comments on this are also mentioned here: viewtopic.php?p=13319#p13319

The obvious conclusion here is that Rudolf can assert with a high degree of confidence that he did not detect cyanide in his samples, whereas Markiewicz cannot assert the reverse due to his negligence with regards to false positives and his cavalier approach to detection limits.

With regards to the overall Holocaust debate the implications are important. The degree to which experts rely on this paper (such as Green and Terry) without commenting on this is unsatisfactory. Terry I guess could be excused as it is outside of his discipline, but Green's omission on this point is especially noteworthy. Green for his part re-iterates the Markiewicz methodology in his own report to the Irving trial:

Markiewicz et al.
did an extremely intelligent analysis that differs from the supposed results of Leuchter and Rudolf in
several ways:

1) They tested for a true marker for exposure to HCN, i.e., the presence of cyanides not
complexed to iron.
2) They used a method with high sensitivity (3 μg/m 3).

3) They calibrated their method against standards of known concentration during the detection
process.
4) They measured a true control: living quarters that were probably fumigated with HCN, but only
once.
It should be noted that the samples collected by the IFFR were obtained legally allowing them the
luxury of scraping samples from locations that were somewhat sheltered from the weather.

https://phdn.org/archives/holocaust-his ... affweb.pdf

Before his confident victory lap:

"The work of Markiewicz et al., on the other hand shows unambiguously that
that the gas chambers were exposed to more cyanide than were the living barracks"

Failure on Green's part to critically assess or even address these limitations is shocking.

Further down the totem pole you have online activists who uncritically repeat and cite the Markiewicz paper without much (or any) understanding of it's contents. Threads like this can at least be a tool to rebut and refute their clammering that Markiewicz found cyanide in Auschwitz!

HansHill wrote: ↑Sat Aug 22, 2026 3:40 pm Agreed. Another additional point worth mentioning when discussing Markiewicz and his detection limits, is that of carbonates as false positives in detecting cyanides. Rudolf explains this in TCOA section 8.2.2 as follows:
...

There is a line in the Epstein paper that says something about the carbonates being noninterfering.

Phosphates, carbonates, chlorides, ammonium salts, borates, sodium salts, cyanates, oxalates, ferricyanides, ferrocyanides, and sulfates have been tested and found noninterfering. (pg. 273)

So the carbonates might be less of an issue with this method because it doesn't require as aggressive an extraction as tests for total cyanide (which have to extract cyanide from the Prussian blue). In other words, Germar's 10 mg/kg is for his total cyanide test. This alternate method may well be lower. But is it really zero? There might be practical considerations that didn't apply to Epstein's pure lab tests.

Whatever the specifics here, common sense would say that as you move down to more and more infinitesimal values (3 ppb is 0.0000003%) that the chance of spurious results increases. Especially when you consider the researcher degrees of freedom in play here and the fact that they were heavily incentivized to obtain a particular result (to put it mildly).

The total cyanide results are extremely robust and have been replicated multiple times. (If it didn't replicate, the Poles could have easily demolished Leuchter and Rudolf on those grounds). Furthermore, we can see the difference with our own eyes. But for these results of only some tens or hundreds of micrograms we must be willing to take the Poles at their word, essentially. And without much evidence presented addressing the possibility of false positives.

One interesting part of the Markiewicz report is where they present results of experimental tests.



What is interesting to me here is that this seems to confirm empirically that the gas dissipates very quickly. They're getting at most 2.7 ppm after 48 hours. And then say it will decrease 28% to 86% after a month. After 45 years there's not going to be much of anything there. I suppose their argument would be that there would be lots of false negatives but no false positives. But that depends on the core claim of extremely fine accuracy which they did not really support.

The second table there is also interesting because it seems like they are really trying to thread the needle. Seems like they want to say the moisture and materials and were favorable. But not favorable enough for any Prussian blue to form.

Archie wrote: ↑Sun Aug 23, 2026 1:47 pm

HansHill wrote: ↑Sat Aug 22, 2026 3:40 pm Agreed. Another additional point worth mentioning when discussing Markiewicz and his detection limits, is that of carbonates as false positives in detecting cyanides. Rudolf explains this in TCOA section 8.2.2 as follows:
...

There is a line in the Epstein paper that says something about the carbonates being noninterfering.

Phosphates, carbonates, chlorides, ammonium salts, borates, sodium salts, cyanates, oxalates, ferricyanides, ferrocyanides, and sulfates have been tested and found noninterfering. (pg. 273)

So the carbonates might be less of an issue with this method because it doesn't require as aggressive an extraction as tests for total cyanide (which have to extract cyanide from the Prussian blue). In other words, Germar's 10 mg/kg is for his total cyanide test. This alternate method may well be lower. But is it really zero? There might be practical considerations that didn't apply to Epstein's pure lab tests.

Yes this is a fair point and I should have noted this, so thanks for raising it. I don't think this does as much heavy lifting as you suggest, and IMO we are right back to square one, in that "we don't know". And the main reason we don't know is yet again, Markiewicz isn't telling us. Firstly, Epstein's method is performed using a simple aqueous solution (ie a perfect, laboratory clean slate as you rightly mentioned above), to which he states carbonates were tested for and found to be non-interfering. A major point here is that don't know the concentration he was testing for. It's also important to note that Epstein's carbonates only appear at the color-determination phase, and are not complexed into his samples, as per Markiewicz.

Given that Markiewicz's workflow was far removed from Epstein's "clean slate" aqueous solution, and rather was performed on a heavily carbonated masonry sample from the jump, in order for Markiewicz to be acting in good faith, he would have to believe Epstein's carbonate concentration was on a par with that of his own masonry samples (!) to be an equivalent assumption of non-interference.

Even with all of these Hail Mary assumptions in mind, Markiewicz at least owes it to the reader to explain this assumption, and why he believes it is merited. Lets not forget that Markiewicz penned his paper (1994) after the Meussen / Temminghof paper of 1989 - meaning in order to be thorough, he should have followed Epstein's lead, and prepared his own test for interferences, which he categorically has not done, but all of Epstein, Meeussen and Rudolf have! Preparing a basic interference test is a standard analytical practice when modifying a known method and utilising a different matrix. This is especially true when you are asserting so confidently that you have enhanced the accuracy!

The total cyanide results are extremely robust and have been replicated multiple times. (If it didn't replicate, the Poles could have easily demolished Leuchter and Rudolf on those grounds). Furthermore, we can see the difference with our own eyes. But for these results of only some tens or hundreds of micrograms we must be willing to take the Poles at their word, essentially. And without much evidence presented addressing the possibility of false positives.

This is still the most critical point in all of this, and makes the Markiewicz experiment as presented all but redundant. All of the above methodological squibbling is next to redundant, as it is an attempt at capturing data of free associated cyanidies which are not expected to be a reliable fingerprint into the past, when there were enormous deposits of iron-bound cyanide right there which have been dishonestly omitted.

"We omitted Prussian Blue because its formation is not a reliable marker for the presence of cyanide"

But it is there!


**Edit**

I forgot to also say, that Epstein's method was known and discussed by Meeussen in his 1989 paper. It appears as citation 3 in that paper: https://sci-hub.box/10.1039/AN9891400959