London - As any detective will tell you, to solve a murder it is crucial to know the exact time of the victim’s death.
It can mean the difference between an alibi holding water or being discounted – and was previously only possible up to 36 hours after the unfortunate event.
But now Austrian scientists have come up with a method that allows calculation of the time of death even after ten days.
By looking at how proteins in pig muscles decay, they get an accurate guide as to when life ended. The process of the muscle tissue degrading is similar to what happens when steaks are aged – and researchers have now started experiments on human samples.
Dr Peter Steinbacher, who is leading the University of Salzburg study, said: “We were able to detect similar changes and exactly the same degradation products in human muscle tissue as we had in our pig study.” Benefits of the technique include the ease of collecting a tissue sample and the fact that relevant tests can be carried out in a day.
Some of the proteins analysed in the study – which was presented to the Society for Experimental Biology yesterday – had still not completely degraded until after the ten days were over, meaning that tests could become even more accurate in future.
Dr Steinbacher said: “It is highly likely that all muscle proteins undergo detectable changes at a certain point in time, and this would extend the currently analysed timeframe even further.” Pathologists are currently able to estimate the time someone died by measuring their body heat up to 36 hours after death. Normal body temperature is 37C (98.6F), with a cadaver cooling down by around 1.5C every hour before reaching room temperature.
Once 120 hours have elapsed, it becomes possible to use an approach that measures the number of insects that have grown.
The research is published in the International Journal of Legal Medicine.
Daily Mail