A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die and a new generation grows up that is familiar with it. 

Max Planck, Scientific autobiography, 1950

On September 30, 2022, I mentioned and linked to a new paper, Ultraviolet fluorescent detection of elevated bilirubin in dried blood serum by Kelly Kearse, that had just been published a week earlier in the Journal of Forensic Science and Research. The journal is an open-access journal available to everyone without charge. My excuse for doing so, if I needed one, was that the paper was interesting and informative about bilirubin, which, like it or not, will be part of the scientific lore of the Shroud for a long time. Maybe I should have said so then.

Colin Berry was displeased with me. “You’ve resurrected the mistaken link with bilirubin, Dan,” he lamented. He did so with comments to the posting and with an email to me. Colin has a point: a good point. But I disagree. So, with his kind permission, I am sharing his email and commenting, myself. He writes:

Why oh why did you bother doing a post on the Kelly Kearse bilirubin paper Dan? 

It had nothing whatsoever to do with the TS. The latter does not get a mention anywhere in the paper per se, being concerned entirely with mainstream bilirubin biochemistry and physiology only. Yes, there is a single mention of the TS, but not in the paper itself. It’s a reference to an earlier June 2020 paper from Kelly Kearse, which did address the TS for sure. But guess what: it addressed two ways in which red bloodstains on the TS had been (erroneously) linked to bilirubin, but then proceeded to dismiss both!

You’ve resurrected the mistaken link with bilirubin Dan, when it was dismissed in 2020 and indeed much earlier (by myself and others).

Are you going to insert a correction or not Dan? If not, you’re guilty of reviving what should have been cleared out of the TS literature a long time ago (indeed, should never have been proposed by Adler in the first place, given that bilirubin is not, repeat NOT red!



In an ideal world, bilirubin as an explanation for the old blood’s red color might well have been dismissed — cleared out of the TS literature, so to speak — on the basis of what Colin and others had to say. But it’s not an ideal world. It’s messy. There are dozens upon dozens of books, many still in print, and many perpetually available as eBooks or print-on-demand paper editions from Amazon. Many, perhaps most still, claim as a fact or likely explanation what Al Adler suggested as a possibility: the blood remained red in appearance because of bilirubin. And it is not just books: papers, articles, interviews, podcasts, blog posts, and other forms of social media say the same thing: bilirubin. Countless papers on Academia are largely undated as are many papers in other repositories such as shroud.com. When articles are dated, readers don’t always notice and wonder about newer information. They may not scrutinize an article’s publication date against benchmark dates for newer information. Google the subject and you are likely to get — it’s red because of 1) hemolytic substances, 2) bilirubin, 3) paint pigment or 4) and/or radiation.

As an example consider this mid-year 2018 article in Aleteia: New study on Holy Shroud confirms: “It’s the blood of a tortured man.” Aleteia is a publication primarily for Catholics. This quote is from the English edition, which alone has 1.6 million readers (unique visitors per month on average).  Excuse the longish (fair use) quote:

A new four-year study, published in the scientific periodical Applied Optics, focuses on the Shroud, returning to the discussion of the authenticity of the Holy Shroud and questions raised by an examination of the blood conducted by Borrini and Garlaschelli. One of the objections raised concerned the color of the coagulated blood — rather than appear brown like normal coagulated blood, in the case of the Shroud, the color appears to be “too red.”

Those shades of red—explains Vatican Insider—were studied after the exposition of the Shroud in 2015, with lasers and optical instruments that also were used to determine if the image of the man has deteriorated (regarding the latter question: no).

The results: “The blood remains red if struck by ultraviolet rays of the same kind as those of sunlight,” explains Paolo Di Lazzaro, Enea researcher and vice-director of the International Center for Shroud Studies, which underwrote the study together with Inrim and Car researchers.

But, be careful—the devil is in the details—the phenomenon only happens with one particular kind of blood: “That of a person suffering from jaundice, or of someone who has been tortured.” The study was carried out on a sick person, “since we couldn’t torture anyone,” jokes Di Lazzaro. The hypothesis had already been formulated, and “we verified it, and we showed that the stains are true blood, there is ancient hemoglobin, not ochre or something else, although there are some people, such as the Cicap, who continue to say the opposite.”

“The purpose,” explains Gian Maria Zaccone, director of the Center for Shroud Studies, “was to understand the reason for the red color of the bloodstains on the Shroud of Turin, a question much debated and about which many hypotheses have been made over time; regarding these, the study has made it possible to verify to what extent some of them are well-founded.” The work was carried out “using colorimetric measurements acquired in the past using non-invasive techniques that do not require physical contact.” Without entering into technical details which “I has a historian leave to experts in the matter, we can however say that there is an ulterior experimental explanation able to justify the particular color; moreover, it is also present in many ancient findings of people whose blood presents a very high amount of bilirubin, as well as elements that make it apparent that we are dealing with ancient blood.” The article “therefore introduces further elements into the recently-raised question regarding the authenticity and the characteristics of the blood present in the Shroud’s image.”

Are we to imagine that among these scientists, just two years later, truth triumphed and they were convinced from what Colin and others said and wrote, particularly, perhaps, by what Kelly Kearse wrote in his 2020 paper. Kelly wrapped it up thus:

In conclusion, the current study has evaluated two major hypotheses related to the reddish color of the bloodstains on the archaeological textile, the Shroud of Turin. By several measures, these data indicate that the reddish color does not result from hemolysis (the hemolytic or Saponaria hypothesis) or is due to increased levels of bilirubin in various forms (the bilirubin hypothesis).

Or, should we think, that truth triumphed among readers of popular press and social media outlets? No! We, untrained as scientists, unlike Colin and Kelly, are poorly equipped to be careful discerners. The massive inertia of the bilirubin speculation by Al Adler has not quite budged in the public mind. It’s the rubber tree and I and my postings are but the nudges of an ant with high hopes. But I get Colin’s point. It should be as he says. But it’s not.

To shamelessly repeat myself: My excuse for mentioning Kelly’s paper, if I needed one, was that the paper was interesting and informative about bilirubin, which, like it or not, will be part of the scientific lore of the Shroud for a long time. I didn’t say so when I should have, so now I’ve said it twice.

I don’t think I have resurrected bilirubin — it lives on still. Max Planck is right.