Final answer:
The long-term effects of repeated radiation exposure can include cancer, cataracts, and a decrease in life expectancy, with the risk of cancer being proportional to radiation dose according to the linear hypothesis. The effects are cumulative, with limited self-repair capacity after exposure.
Step-by-step explanation:
The possible long-term effects of repeated exposure to radiation include cataracts, cancer, and a decrease in life expectancy. Repeated or chronic exposure to radiation can lead to genetic defects and is correlated with an increased risk of various types of cancer, as demonstrated by significant research involving survivors from atomic bombings and nuclear disasters such as Chernobyl. Notably, any level of radiation may pose a risk to human health, with evidence suggesting that long-term effects of radiation are cumulative and that self-repair mechanisms are limited.
Specifically, the risk of developing cancer such as childhood thyroid cancer, which has been observed to increase following radiation exposure, is usually assumed to be proportional to the risk at high doses - an assumption known as the linear hypothesis. Moreover, the onset of radiation-induced cancer has a latency period, indicating that the individual remains at risk for an extended period after initial exposure. All of these points underscore the importance of minimizing unnecessary exposure to radiation.