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What are the biological effects of ionizing radiation?


One characteristic of ionizing radiation on human body is that the energy absorbed is low but the biological effects are serious. For example after receiving a lethal dose of 10 Gy, the body temperature will only increase by 0.02 oC but the dose may lead to death of all the exposed entities.

The second characteristic is the latent biological effects of radiation. Acute biological effects can occur within several hours to several days while the long term effects usually appear several years after the exposure.

Type of effects

Generally speaking, the biological effects of ionizing radiation can be classified according to the characteristics of effects, occurring times and the object that shows the effects.

Characteristic of effects Occurring time Object Effects on organs
Deterministic Effects Acute Effects Somatic Effects

Skin damage
Damage of reproductive system
Damage of blood forming system
Damage of digestive system
Damage of central nervous system

Latent Effects


Damage of immunization system

Stochastic Effects


Genetic Effects Heredity effects


The effects of critical organs

Different organs have different sensitivity to ionizing radiation. For example, gonad and bone marrows are more sensitive organs, but the bones are less sensitive. For more information on organ sensitivity please press here.



The above information is provided by RHD of DH
Department of Health

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Last revision date: <01 Oct 2019>