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They could do. You could pull the front brake and go over the handle bars, smash all your teeth out. Probably won’t though. I wouldn’t worry about it until it happens, it will be noticeable before anything bad happens. And to be honest, it will probably be really hard to get out anyway as most old bottom brackets usually are. Unless it’s loose I wouldn’t give yourself an extra job to do
I think it is french threaded and it can get loose according to what I read. But I will show it to a mechanic to hear an expert's opinion.