As in the case of marie curie, prolonged exposure to radioactivity of any kind can lead to all but one of these results

Pneumonia is not a result of prolonged radioactivity exposure, most especially regarding the cause of death of Marie Curie. In fact, pneumonia is primarily caused by bacteria and viruses infecting our lungs most specifically the alveoli. This alveoli gets filled with fluid, like water, that would cause extreme coughs.

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because of