Heated Prose at Futility Closet.

Marie Curie’s laboratory papers are still so radioactive that they’re kept in lead-lined boxes.

Researchers who consult them must agree to work at their own risk.

I should point out that it’s unlikely to be because the papers were irradiated, but because they were contaminated. Neutron activation can result in a radioactive nucleus, but exposure to gammas and alphas generally does not. I think that “irradiated” is often misunderstood to mean “contaminated.” Irradiated means exposed to radiation. Contaminated means radioactive materials have become attached to the object.