Case Report

Time to Terminate LNT: Radiation Regulators Should Adopt LT

Jeffry A Siegel*, Bill Sacks and James S Welsh3

Published: 26 June, 2017 | Volume 1 - Issue 2 | Pages: 049-053

The linear no-threshold hypothesis (LNT)-the basis of radiation regulatory policy-extrapolates from observed high-dose harm to assumed low-dose harm, entailing that all ionizing radiation is harmful, by denying any biological response to damage and asserting cumulative lifetime harm, regardless of dose or dose rate. All aspects of LNT are demonstrably false. There are evolved biological responses that repair or remove radiogenic damage from low doses and dose rates, thereby averting acute harm and precluding the alleged cumulative damage. LNT and its offspring, the “as low as reasonably achievable” principle, do not err on the side of caution; neither is truly conservative. The public needs protection from radiophobia, rather than from low-dose radiation exposure. Neither radiation regulations nor medical practice should be based on LNT, but rather, at least as a first step, on a linear (down to a) threshold (LT) model.

Read Full Article HTML DOI: 10.29328/journal.jro.1001007 Cite this Article Read Full Article PDF


Linear No-Threshold (LNT) model; ALARA; Low-dose radiation risk; Adaptive response; Radiation protection; Radiation carcinogenesis


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