Radiation Risk

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Biological Effects of radiation: Stocastic (delayed) effects and Non-stocastic (deterministic) effects Stocastic (delayed) effects
- cancers in exposed individual: observed 3-20 years after exposure ;
- Mutations in offspring of exposed individual - observed in future generations
Probability of effect increases with dose, with no dose threshold, but the severity of the effect is not dose related. E.g. radiation induced cancer and genetic effects. Playing the Lottery game, more exposure, more chances of effect.
Cancer risk: average risk for radiation induced cancer in general population is 5% per Sievert (Sv); Children are 2-3 times at higher risk then adults (as high as 15% per Sv); for persons aged >50 yars risk is 1/5 to 1/10 of the for younger adults

Non-stocastic (deterministic) effects:
- direct damage to tissue due to local cell death;
- observable within days to weeks
Threshold dose; >2 Grey of radiation 

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