Final answer:
Chronic doses of radiation are the health hazards that take years to develop, with cancer and genetic defects being the known long-term effects.
Step-by-step explanation:
The health hazards from radiation that take years to develop are associated with chronic doses of radiation. Unlike acute or lethal doses, chronic doses consist of exposure to radiation over a long period of time. The two known long-term effects of such exposure are cancer and genetic defects. Both of these effects result from the interference of radiation with cell reproduction. Studies from the atomic bomb survivors of Hiroshima and Nagasaki, occupational exposures, and the Chernobyl disaster have provided evidence that cancer can develop years after exposure to radiation. The linear hypothesis suggests that any dose of radiation has an associated risk to human health, no matter how small, and these long-term effects are cumulative with little self-repair capacity in the body.