The episode also pays tribute to geochemist Clair Patterson (voiced by Richard Gere) in his quest to remove the neurotoxin lead, from gasoline.
[1] The episode's title alludes to Patterson's attempts in sterilizing his lab after realizing that the inconsistent results in his experiments were due to lead contamination.
[2] The episode describes how science, in particular the work of Clair Patterson (voiced in animated sequences by Richard Gere) in the middle of the 20th century, has been able to determine the age of the Earth.
Tyson then outlines the work Patterson did as a graduate under his adviser Harrison Brown to provide an accurate count of lead in zircon particles from Meteor Crater, and to work with similar results being collected by George Tilton on uranium counts; with the established half-life of uranium's radioactive decay to lead, this would be used to estimate the age of the Earth.
Tyson ends by noting that similar work by scientists continues to be used to help alert mankind to other fateful issues that can be identified by the study of nature.