What is LNT model?
- The Linear no-threshold model (LNT) is the most commonly used model to estimate the biological risks from ionizing radiation.
- The LNT model states that biological effects such as cancer and hereditary effects due to exposure to ionising radiation increase as a linear function of dose, without threshold.
- The linear no-threshold model is based on biological responses at high radiation doses and dose rates.
- The higher the dose and dose rate, the higher the biological response; the lower the dose and dose rate, the lower the response.
- This model assumes the simplest possible relationship, a straight line (hence linear no-threshold model).
Uses of LNT Model
- The LNT model helps agencies to regulate radiation exposures to diverse categories of licensees, from commercial nuclear power plants to individual industrial radiographers and nuclear medical practices.
What is ionizing radiation
- Ionizing radiation is a type of energy released by atoms in the form of electromagnetic waves or particles.
- People are exposed to natural sources of ionizing radiation, such as in soil, water, and vegetation, as well as in human-made sources, such as x-rays and medical devices.
- Ionizing radiation has many beneficial applications, including uses in medicine, industry, agriculture and research.
- As the use of ionizing radiation increases, so does the potential for health hazards if not properly used or contained.
- Acute health effects such as skin burns or acute radiation syndrome can occur when doses of radiation exceed certain levels.
- Low doses of ionizing radiation can increase the risk of longer term effects such as cancer.
Why in News:
- The U.S. Nuclear Regulatory Commission (NRC) upheld the Linear No-Threshold model to prescribe radiation safety standards.
- Petitioners’ proposed substantial increase in dose limits to workers; raise the public dose limits to be the same as the worker doses; end differential doses to pregnant women, embryos and fetuses, and children less than 18 years of age.
- Convincing evidence has not yet demonstrated the existence of a threshold below which there would be no stochastic effects from exposure to low radiation doses. As such, the NRC’s view is that the LNT model continues to provide a sound basis for a conservative radiation protection regulatory framework that protects both the public and occupational workers.