Uranyl acetate for staining is typically depleted and unless you have regulatory issues I don't think the radiation is a big concern, especially when you compare to the very serious toxicity of OsO4 (vapors can react with your eyes and blind you).
Interesting and makes sense! I know nothing but what I read from the stain description haha. OsO4 seems incredibly nasty. So do a few other of the stains!
