A new way to calculate time of death

Researchers from the University of Salzburg have developed a new method for reliably calculating time of death at least 10 days post-mortem — a substantial increase from the current timeframe of 36 hours.

The scientists observed how muscle proteins and enzymes degrade in pigs, finding that some of the proteins analysed (eg, tropomyosin and actinin) showed no form of degradation until after 240 hours. Specific degradation products of proteins appear at a specific time after death; therefore, by studying the timing of their appearance, the researchers were able to calculate time since death.

“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,” said Dr Peter Steinbacher, the leader of the research.

The use of muscle tissue in a post-mortem presents several advantages. Firstly, muscle tissue is the most abundant tissue of the human body and can therefore be sampled easily. Secondly, proteins in muscle tissue are well known. Thirdly, the method is simple and can deliver results within a day.

The researchers have already started running experiments on human samples and initial results are 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,” said Steinbacher.