The LNT Model

This 4-minute youtube video [] is excellent. Very clear, lucid, crisp and brief — just what the busy scientist wants. The bottom line is that the Linear Non-Threshold (LNT) Model is not founded on scientific facts. Instead, wherever possible, we should base all governmental policies on scientific, evolutionary-based data.

Let’s hope that powerful leaders in the U.S. EPA, and other regulatory agencies are listening. ☹



Please watch this 4-minute video summary by John Cardarelli (President, Health Physics Society) on the LNT story. It is impressive and should be shared widely. Most people are more prone to watch a short (but powerful) conceptual summary than delving into many dozens or hundreds of pages of text, describing this fraud…

Ed Calabrese

[I always open “CC” (closed captions), if it’s available, to help me understand what speakers are saying.]

To refresh everyone’s memory about the “LNT Model,” recall that GEITP has discussed this topic at least a half-dozen times. Ed Calabrese, emeritus in environmental health sciences at University of Massachusetts Amherst, has authored and coauthored more than two dozen papers — starting about 2011 — on questioning the scientific conclusions of the fruit fly experiments leading up to the infamous Linear Non-Threshold (LNT) Model for risk assessment (originally) for ionizing radiation exposure. The LNT Model arose from the 1946 Nobel Prize awarded to Hermann Mueller — and was adopted by the U.S. Environmental Protection Agency (EPA) and many other agencies. And, by extrapolation from ionizing radiation, it was proposed that this same model likely holds true for most (if not all) chemical toxicants and carcinogens.

In his Nobel Prize Lecture on December 12, 1946, Hermann J. Muller argued that the dose-response for ionizing radiation-induced germ cell mutations was linear and that there was “no escape from the conclusion that there is no threshold.” However, a recently discovered (by Calabrese in 2015) commentary by Robert L. Brent indicated that Curt Stern, after reading a draft of part of Muller’s Nobel Prize Lecture, telephoned Muller — strongly advising him to remove reference to the flawed linear non-threshold (LNT)-supportive Ray-Chaudhuri findings and strongly encouraged him to be guided by the threshold supportive data of Ernst Caspari [who, incidentally, was DwN’s genetics mentor in college]. Brent wrote that Mueller refused to follow Stern’s advice, thereby proclaiming (during his Nobel Prize Lecture) support for the LNT dose-response, while withholding evidence that was contrary. This finding is of historical importance, because Muller’s Nobel Prize Lecture then gained considerable international attention in 1946 and was a turning point in acceptance of the linearity model for radiation and chemical hereditary and carcinogen risk assessment.

Ed asserts that the science used — to support the LNT model adopted by the NAS’s 1956 Biological Effects of Atomic Radiation (BEAR) I Genetics Panel — was also tainted by its leaders, who he says deliberately refused to include evidence from NAS’s own Atomic Bomb Casualty Commission (ABCC) human genetic study, also known as the Neel and Schull 1956a report.

Calabrese says Neel and Schull showed “an absence of genetic damage in offspring of atomic bomb survivors, which supports a threshold model (i.e. not the LNT model),” but this was not considered for evaluation by the genetics panel, “therefore, those data could not figure into its decision to recommend the erroneous LNT dose-response model for risk assessment.”

Calabrese suggests that the panel’s work was undermined by Hermann J. Muller and BEAR I chairman Warren Weaver, who “feared that human genetic studies would expose the limitations of extrapolating from animal, especially the fruit fly, Drosophila, to human responses, and admitting this would strongly shift research investments/academic grants from animal to human studies.”

Calabrese adds, “The country expects its scientists to be honest and to follow real data. The BEAR 1 Genetics Panel failed on both counts, being loyal only to their ideology, and then hiding it. They were hailed by many media outlets as the Genetics Dream Team — giving them ‘further cover’ so that their deceptions would never be known. They have gotten away with it, so far, for 68 years.” How much longer will we believe that “inaccurate scientific conclusions do not lead to bad government policy” — which continues to be practiced, today…??

“This history should represent a profound embarrassment to the U.S. NAS, regulatory agencies worldwide — and especially to the U.S. EPA and the risk-assessment community — whose founding principles were so ideologically determined and accepted with little, if any, critical reflection.”


Number of the Week: “100,000 times greater (than background).” According to Ed Calabrese, Hermann Mueller knew of Caspari’s University of Rochester study — before he gave his Nobel talk in December 1946.

“That [fruit fly] study had shown that at the ‘low’ chronic radiation dose rate (i.e., yet still about 100,000 times greater than background), no radiation-induced mutation effects were found. The Caspari study supported the threshold model, and not the LNT model.”

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