10 Key Points from “LNT, LWT, SNT and the Radium Dial Painters”

  • The paper compares three radiation risk models: LNT (Linear No-Threshold), LWT (Linear With Threshold), and SNT (Sigmoidal No-Threshold).

  • LNT assumes any amount of radiation is harmful, with risk increasing linearly.

  • LWT assumes there is a safe threshold (~100 mSv over 3 days) below which no harm occurs.

  • SNT uses an S-shaped curve, suggesting gradual risk increases and allowing for natural biological repair.

  • Data from radium dial painters show that LNT overestimates cancer risk, while SNT matches real data better.

  • At low doses (<2 mSv/day), all models are similar, but LNT becomes overly pessimistic at higher exposures.

  • At high doses (40–80 mSv/day), cancer incidence increases but never exceeds 40%, contradicting LNT predictions.

  • Fukushima case study: LNT predicted 12% cancer mortality, SNT predicted 0.016%, and LWT predicted near zero.

  • LWT can produce unrealistic results above the threshold, sometimes exceeding 100% predicted incidence.

  • The author concludes SNT is the most accurate model and recommends shifting radiation regulations away from LNT-based policies.