And not just before 1945: lead is used for radiation shielding, but freshly-mined lead is slightly radioactive itself... shipments of lead that were mined 2000

And not just before 1945: lead is used for radiation shielding, but freshly-mined lead is slightly radioactive itself... shipments of lead that were mined 2000 years ago and sitting at the bottom of the Mediterranean since then, much less so: https://www.nature.com/news/2010/100415/full/news.2010.186.html https://www.nature.com/news/2010/100415/full/news.2010.186.h...