True crime meets forensic science in the What Remains podcast
Oct. 26, 2022

Isotope Analysis: A Roadmap Through Someone’s Past

At first, Professor Glen Jackson, who teaches Forensic and Investigative Science at West Virginia University, had a hard time explaining to me what isotopes are. He told me he is used to speaking with chemists, not lay people like myself. In fact, he said, it was unusual for lay people to be interested in his work. But he had me hooked from the moment he explained how isotopes were like a roadmap of our geographical lives. 

I told him to break it down for me like I know nothing about the science, which is pretty close to the truth. And so he did. He told me that isotopes are in our bodies are formed and changed by the water we drink and the food we eat that either ingests water or is cooked in water. Plainly speaking, the water in Toledo, Ohio is not the same at the water in Portland, Maine. 

The key to isotopes is in the water we consume 

He explained how our teeth, and some bones, hold onto the isotopes of the region where we were born and raised. Later, isotopes in our hair, for example, can show scientists where we moved to or where we traveled. This kind of information is invaluable to forensic genealogists in cold cases who are trying to create a family tree of a victim, but don’t know where to begin. 

How isotope analysis is used in forensic science 

Professor Jackson explained how isotope testing in combination with DNA testing can help solve cold cases at a much higher rate. He dove into the “Scissor Sisters” case in Ireland where a man was found dismembered in the Royal Canal in Dublin. Isotopes helped tell investigators he was from Africa, and had spent many years there before moving to Ireland.  

The professor believes the sky is the limit when it comes to isotopes, that someday, they will be able to reveal other characteristics with even more with certainty like age, sex, and even medical conditions.  

In episode 16 of the What Remains podcast, we explore the growing field of isotope analysis and how it may just be better than a GPS at telling scientists where someone has been in the world.