The Clock Is Ticking: New Test Can Determine Time of Death Up To 10 Days
Determining the exact hour at which someone passed away is a morbid, but necessary, scientific endeavor. Calculating the time of death has been imperative to solving murders, and to recreating the scenes of accidents to understand how events unfolded. The second a person dies, though, their body begins to change in ways that make calculating the time of death an urgent matter. If forensic specialists don’t figure it out before time is up, the knowledge will be lost forever.
A new, unorthodox method for determining the time of death may be the key to extending this crucial window of time. It seems researchers at the University of Salzburg have unlocked the secret to revealing the exact time of death, and they did it using pigs.
By observing the way certain muscle proteins and enzymes degraded in pigs, the scientists developed a new way to calculate time of death, up to almost 200 hours longer than had previously been possible. The researchers saw that some proteins analyzed (including tropomysin and actnin) did not degrade until after 240 hours.
"It is highly likely that all muscle proteins undergo detectable changes at a certain point in time, and this would extend the currently analyzed timeframe even further," said Dr. Peter Steinbacher, the lead researcher of the study, in a press release.
Knowing that specific proteins degrade at specific times after death — and becoming familiar with the timing of their degradation — would allow researchers to determine the exact amount of time since death.
Current methods of calculating the time of death include measuring body temperature, Rigor Mortis and decomposition, and these only allow us to determine the time of death prior to 36 hours. This new enzyme method would extend the period to 10 days, and initial experiments on human tissues look promising.
"We were able to detect similar changes and exactly the same degradation products in human muscle tissue as we had in our pig study," Steinbacher said.
Using muscle tissue in post-mortem studies is a somewhat novel approach, but offers several valuable advantages. Muscle is the most plentiful tissue in the human body, so finding a sample for testing would never be a problem. The proteins in muscle are well known to scientists, and the methods they use to sample them are relatively simple. Results can be delivered within a day.
Dr. Stuart Hamilton, a forensic pathologist from the University of Leicester, commented on the research saying it was interesting and valuable, but it will take time before becoming a commonly used method.
He told BBC: "There is so much riding on the time of death in many murders that we will all as a forensic and legal community have to be very convinced that there are no confounding factors before we start relying on this to convict someone."