Don't you worry about the residual RADIUM
from the luminous dials?
The Big Bang Theory Season 2, Episode 1
Madam Curie's discovery of RADIUM
turned out to have great potential...
The Big Bang Theory Season 1, Episode 2
♪ Six times ten to the eighth
atoms of RADIUM ♪
The Big Bang Theory Season 12, Episode 23
bathed in the glow of their love
and the RADIUM
The Big Bang Theory Season 5, Episode 16
♪ Of a RADIUM in a lead jar
The Big Bang Theory Season 12, Episode 23