Question

•Skeletal remains of the colonial era occupants of the Caribbean islands show high levels of lead, high enough that they should have been experiencing symptoms. The lead may have come from bottles used for rum, their leading cash crop. It may have come from glazes on their pottery used for food handling, especially acidic fruit. etc. We have found a very few of such bottles, sealed but empty. We believe they once held rum. The inside surface may house lead residues. We would like to know, but we mustn’t break or otherwise damage (e.g., scrape) the bottles. How could we get this information ? Explain in detail, showing numbers, not generalities.

Answer 1

We can use XRF (X ray Fourescence) or Radioactive Isotopes to detect the lead inside the bottles, without damaging them. Lead is known to be used in blocking radioactivity. Let us say that the Lead has a Half value layer of h meters, for the radioactive isotope we have in our radioactive device. Let us say that the amount of lead inside bottle has a thickness t, then we will allow the radiation to pass through and then detect this radiation. Let the source Intensity be I0 and the detected intensity be I, then we can write,

Here n is from the information about Half-value layer which is,

Therefore the final Intensity is,

Rearranging and applying log we can write,

Therefore by using the above formula we can find the content of lead in the bottles.