Journal of Environmental Health Sciences (한국환경보건학회지)

Korean Society of Environmental Health (한국환경보건학회)
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The Linear No-Threshold Model in Epidemiological Studies: An Example of Radiation Exposure

역학연구에서의 비역치선형모델: 방사선 노출 사례

  • Won Jin Lee (Department of Preventive Medicine, Korea University College of Medicine)
  • 이원진 (고려대학교 의과대학 예방의학교실)
  • Received : 2024.08.03
  • Accepted : 2024.08.18
  • Published : 2024.08.31
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Abstract

The linear no-threshold (LNT) model is an assumption that explains the dose-response relationship for health risks, allowing for linear extrapolation from high doses to low doses without a threshold. The selection of an appropriate model for low-dose risk evaluation is a critical component in the risk assessment process for hazardous agents. This paper reviews the LNT model in light of epidemiological evidence from major international consortia studying ionizing radiation. From a scientific perspective, substantial evidence supporting the LNT model has been observed in epidemiological studies of low-dose ionizing radiation exposure, although some findings suggest non-linear dose relationships for certain cancer sites and variations across populations. From a practical standpoint, the LNT remains the most useful model for radiation protection purposes, with no alternative dose-response relationship proving more appropriate. It is important to note that the LNT model does not directly reflect the magnitude of risk at the population level, and this distinction should be clearly communicated to the public. While applying the LNT model as the principal basis for radiation protection, continuous research into various dose-response relationships is crucial for advancing our understanding.

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