Australasian Science Magazine

By David Ranson

The remains of Yasser Arafat have been exhumed for “special testing” to determine whether he died from poisoning by a radioactive element or natural causes.

Investigators are looking for evidence of the presence of the radioactive element polonium-210, an alpha particle emitter that causes tissue damage if taken into the body. Polonium allegedly caused the agonised death of Alexander Litvinenko in London in 2006 and it’s been alleged that it was found on some of Arafat’s clothing after his death.

Polonium is notoriously difficult to detect and has a relatively short half-life of 138 days, which means that after eight years (Arafat died in November 2004), the search for it in human tissue will involve some complex chemistry. But apart from the analytical problems and forensic issues of sampling, the exhumation itself will be problematic – largely because of the likely state of Arafat’s remains.

Exhumation explained

A forensic exhumation is a painstaking process that involves far more than simply recovering and examining the body. And when there are allegations of poisoning, examining the material around the body – including the soil in the vicinity of the grave – is as important as the human remains.

The first task is to confirm the exact location of the body so that the physical approach to the remains follows a documented path from which samples of soil, casket material and body wrappings can be collected with minimal contamination from surrounding areas. The survey of the location must include analysis of soil type, ground water flows and identification of the nature of the original grave preparation.

Burials can take place in land that may have been previously exposed to chemicals so that water flows or seepage through soil can result in secondary contamination of a body after death. The details of the body embalming process undertaken before or around the time of the original internment and the chemicals used also need to be known.

Testing the right sample

Upon completion of meticulous sampling and examination of the region around the body, the exhumation proceeds to the recovery of the body itself. So what might the condition of Arafat’s body be after interment for eight years? The answer depends on two main factors.

First, the condition of the body prior to burial and second, the environment in which the body has been interred. Body factors include the presence and quality of any embalming processes as well as the physical and disease status of the body at the time of death. Environmental factors include temperature, soil microorganisms and other fauna, the chemical nature of the soil and its permeability to body fluids as well as any ground water flows through the grave site.

Even after eight years, it’s possible that, if an embalmed body has been lying in well-drained sandy soil, much of the soft tissue of the body might remain. But if the embalming process was poor or the body had started to decompose before embalming began, then there might be considerable soft tissue loss. The loss of body organs through decomposition will probably present an insurmountable problem to any examination of the body for natural disease related causes of death.

What the bones say

It’s likely that skeletal structures will be preserved after eight years but what can be found out will depend on the degree to which any poison was actively taken up by the bones during life. And the degree to which traces of the poison might be lost from the bones after death as a result of decomposition and grave conditions.

Even where poisons are not actively incorporated into bones, they may be present in the bone marrow. Sampling these tissues is more difficult than collecting body fluids or soft tissues but bone sampling and extraction of bone marrow may prove useful in revealing the presence of some poisons after death.

There are many factors that could make the recovery of alleged poisons in Yasser Arafat’s body very difficult. In particular, the characteristics of the grave site, the quality of embalming and the extent of decomposition all make predicting the outcome of forensic analyses almost impossible.

Even if adequate samples can be collected from the grave and the body, it will only be the start of the challenges facing forensic specialists, who will have to determine not only the presence of the radioactive element but whether Arafat was exposed to enough of it to kill him or whether there is evidence of other disease processes that might reflect a different cause of death.