From international organizations to local police forces, a lot of time and effort goes into preventing nuclear or radioactive materials from falling into the hands of terrorist organizations. But should the worst come to pass and either a nuclear device or a radioactive dirty bomb detonate, nuclear detectives would play a vital role in determining the nature of the incident and narrowing down its possible origins. In this respect, the investigation would resemble a traditional crime scene investigation, asking what the murder weapon was, where it came from and who the perpetrator might have been.
Nuclear forensics specialists would first have to determine whether the attack involved radioactive materials. If so, the next step would be to determine whether uranium or plutonium was used and how sophisticated the device was. By studying trace materials left over from the explosion, scientists would be able to study the isotopes and impurities in a sample of uranium or the enrichment level of plutonium to home in on its origins. The presence of high-energy neutrons or tritium would signify that the device was thermonuclear in nature. By comparing the blast site to recorded nuclear weapons tests, investigators could further narrow in on the device design used.
The actual groups responsible for investigating such incidents varies from country to country. In the United States, domestic nuclear forensics experts would turn over all information to the FBI. Other countries or international groups such as the IAEA would only become involved if asked to participate.
But not every event would necessarily transpire on an epic scale. For instance, nuclear forensics played a role in helping British authorities investigate the 2006 death of writer Alexander Litvinenko in London. The former KGB agent became sick following lunch with Russian Andrei Lugovoi. Three weeks later, Litvinenko died of radiation poisoning due to significant amounts of polonium-210 in his system. Investigators were able to follow a trail of polonium-210 back to a hotel room Lugovoi occupied in the weeks leading up to the meeting [source: BBC].
The Litvinenko case stands out as a rare case of suspected homicide by radiation poisoning. But the case also underlines that, despite all the security measures in place, individuals can acquire radioactive materials and use them as a weapon. Some advocates argue that more funding should go to promote the study of nuclear forensics, so as to better prepare the world for possible attacks in the future.
Explore the links on the next page to learn more about radiation, forensics and nuclear weapons.