Childhood exposure to medical imaging radiation does not increase childhood or adult risk of developing cancer, according to a recent report in the Journal of Nuclear Medicine.

The belief that childhood exposure to medical imaging radiation results in increased risk of cancer is based on the linear no-threshold model of ionizing radiation exposure. This model, presented in the 1940s by Hermann Muller, postulates that the dose-response relationship is linear and that there is no threshold dose; in other words, according to this model, all radiation is harmful, even at low doses and dose rates.

This report assessed evidence refuting the linear no-threshold model and its consequent efforts to decrease radiation exposure from CT and nuclear medicine imaging, especially in children.

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Additionally, researchers presented evidence demonstrating that children are not more radiosensitive than adults in the radiologic imaging dose range. This supports dose reduction for children as both unjustifiable and counterproductive.

The authors suggest that adhering to the linear no-threshold model results in radiophobia, which is supported by futile efforts to decrease nonexistent risks. The authors state that radiophobia is detrimental to patients and their families, increases stress, and results in decreased quality of images and increased avoidance of imaging.

The researchers emphasized that these behavioral changes that accompany radiophobia can increase misdiagnoses and consequent harm while providing no benefits.


1. Siegel JA, Sacks B, Pennington CW, Welsh JS. Dose optimization to minimize radiation risk for children undergoing CT and nuclear medicine imaging is misguided and detrimental. J Nucl Med. 2017;58(6):865-868.