Hair-raising forensic breakthrough hailed

Scientists are developing ways to search for clues from radioactive elements in bones and hair that can help police solve crimes. A method of determining when murder victims were killed by analysing radioactive isotopes in their bones is already being used by police forces. The same researchers who developed that technique are now investigating ways of checking isotopes of oxygen and hydrogen in hair that can indicate where a person has been living. Water in different regions of the world produces subtly different isotopic signatures. By checking suspects' hair it may be possible in future for police to determine whether they have been honest about their whereabouts. The scientists' work suggests that a bald-headed individual with no body hair might in future be regarded as a suspicious character. Until now, establishing when murder victims have died from their decomposed remains has proved surprisingly difficult. "There are lots of different methods ranging from visual appearance right the way through to looking at insects and larvae," said Black, a professor from the University of Reading and one of the scientists developing the technique. The problem with those methods is that they are very temperature dependent, whereas the isotopic method is unaffected by temperature. Professor Black's team has now embarked on long term studies asking people about their diets and analysing the isotopic content of their hair. The results are expected in the next year or two.