Markiewicz vs Epstein vs Rudolf - Detection Limits

[Archie]

Yet the exterminationists want to continue to debate what Markiewicz did, and because no one has ever reproduced Markiewicz's unusual methodology, it as if there is no definitive answer to the key question. The way to get a definitive answer is for new testing to be done.

There's no way to validate what they did. We don't know if they presented all their data. IIRC a few of their statements imply that they did do total cyanide tests (and I would be extremely surprised if they didn't) yet it seems they never presented those results. Unlike the total cyanide results, there's no way to confirm what their results. Them doing tests in secret, having some things leaked, and then reluctantly publishing something later is not exactly ideal science. It's like the opposite of preregistration.
https://en.wikipedia.org/wiki/Preregistration_(science)

And even now, if we wanted to replicate their results, I don't see how that would stricly possible. Presumably if samples were retaken and tested for free cyanide you would again get a bunch of near zero (<1 ppm) values. But since free cyanide isn't long-term stable, we would expect the number to change (to go down). If their model is correct (that the free cyanide is all from Zyklon B) the values should generally be lower today than they were in the 1990s. If the values are the same or higher, that would seem to contradict their model since they assume essentially no trace environmental/background cyanide or false readings that would be needed to explain any increases. As for controls, they should have done more originally. If any of those came back with non-zero values that would also disrupt their theory. If the retests looked noisy I think that would undermine their argument (that the free cyanide is from Zyklon B usage from the 1940s which has been gradually declining over time).

[HansHill]

One additional point that belongs in this conversation, is that of the Leuchter samples. These tests were performed blind by Dr Roth of Alpha Analytic Laboratories, an independent third party lab with no prior knowledge of the source. We know they were performed blind, as Roth was later called to testify at the Zundel trial, at which he corroborated his lab's findings under oath.

It is worth noting that the method chosen by Roth to detect cyanide in masonry under blind conditions is the same method that Rudolf chose, and that Rudolf argues is the preferred method. Roth's blind approach inadvertently legitimizes Rudolf's preference, approach, and results over Markiewicz'.

The detection limit under the Roth methodology are consistent with that of Rudolf, as stated by him:

Prof. Dr. J. Roth, Alpha Analytic Laboratories, Ashland, Massachusetts.
For the cyanide analysis, this laboratory used a procedure carried out analo-
gously to the German standard (see 3.).363 Control analyses were prepared for
some test samples near the detection limit of 1 mg cyanide per kg test materi-
al. The results fluctuated up to 40%.

Rudolf, The Chemistry of Auschwitz, 8.2.1

Furthermore, the point about controlling for readings at the detection limit and finding them to be fluctuating wildly, corresponds exactly with the Rudolf explanation of these readings being false positives via carbonates.

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As an addendum to the above and somewhat off-topic for this thread, it must be said that Roth backtracked on all of the above, but of course his backtracking is unsatisfactory. Firstly, we must acknowledge that with all other things being equal, we must bias ourselves towards his statements made under oath. This should be obvious but it is worth mentioning anyway. Secondly, his argument is that cyanide is only expected to be detected on the surface of a wall / masonry sample - and because of Leuchter's samples being almost fist-sized, any residual cyanide out be diluted out of detection range.

This is obviously bunk for many reasons, but primarily because this did not seem to dilute the delousing readings at all (!) The delousing samples seemingly survived the exact dilution Roth says must have obscured the "gas chamber" readings. Curious!