Most of the uranium used to build the atomic bombs were mined in Shinkolobwe in the Democratic Republic of the Congo. The Congolese people had to work in the uranium mines without protection. Exposure to uraniun could result in negative health impacts such as: renal failure, decreased bone formation, cancer, issues with fertility etc. The labor of the Congolese people for the Manhatten Project were kept secret until recently, and still no research has been conducted on the long-term consequences of uranium intake in the people at the extraction site in the Congo.
And this is why the narrative surrounding Oppenheimer (the man himself and the film) makes me angry. The atomic bombs are a product of colonialism. It was a bomb funded by a settler colony (USA), it's materials are dug from a colony (DRC) by colonized people (the Congolese) and tested on colonized lands (Hispanic village of Tularosa and Mescalero Apache Reservation). But, the narrative that always gets perpetuated is of the tragedy of a brillant White man and his deadly creation, the many Black and Brown people who became collateral damage of the creation are always erased. And it says A LOT about whose labor and pain matters.