She worked for 4 years grinding up several tonnes of radioactive pitchblende to separate the Polonium and Radium from it. She developed the X-Ray machine.
And it was another 30 years before she died and it was not even from radioactive poisoning.
FEAR is a good way to suppress Science
Marie Curie the scientist
https://www.mariecurie.org.uk/who/our-history/marie-curie-the-scientist
When the Curies investigated further, they found that the liquid left behind after they had extracted polonium was still extremely radioactive. They realised that pitchblende contained another new element, far more radioactive than polonium, but present in even smaller quantities.
In 1898, the Curies published strong evidence supporting the existence of the new element – which they called radium – but they still had no sample of it. Pitchblende is an expensive mineral, because it contains valuable uranium, and Marie needed a lot of it.
She got in touch with a factory in Austria that removed the uranium from pitchblende for industrial use and bought several tonnes of the worthless waste product, which was even more radioactive than the original pitchblende, and was much cheaper. Marie set about processing the pitchblende to extract the tiny quantities of radium. This involved working on a much larger scale than before, with 20kg batches of the mineral – grinding, dissolving, filtering, precipitating, collecting, redissolving, crystallising and recrystallising.
The work was heavy and physically demanding – and involved dangers the Curies did not appreciate. During this time they began to feel sick and physically exhausted; today we can attribute their ill-health to the early symptoms of radiation sickness. At the time they persevered in ignorance of the risks, often with raw and inflamed hands because they were continually handling highly radioactive material.
In 1902 Marie eventually isolated radium (as radium chloride), determining its atomic weight as 225.93. The journey to the discovery had been long and arduous.