Mr Alexander Litvinenko - Health Protection Agency Statement

Main Category: Radiology / Nuclear Medicine
Also Included In: Bio-terrorism / Terrorism
Article Date: 27 Nov 2006 - 0:00 PDT

email to a friend   printer friendly   opinions  

The Health Protection Agency (UK) can confirm that it is providing expert advice as part of the Metropolitan Police investigations into the death of Alexander Litvinenko.

Tests have established that Mr Litvinenko had a significant quantity of the radioactive isotope Polonium-210 (Po-210) in his body. It is not yet clear how this entered his body. Police are investigating this.

Po-210 occurs naturally and is present in the environment and in people at very low concentrations. As it emits alpha particles, Po-210 can represent a radiation hazard if it is taken into the body - by breathing it in, by eating it, or if it gets into a wound. It is not a radiological hazard as long as it remains outside the body.

The Agency is providing radiological protection advice to staff at the two hospitals which treated Mr Litvinenko and specialist monitoring teams will also d etermine whether any radioactive polonium-210 contamination has spread in the hospital areas he was cared for. Other specialist monitoring teams will examine other locations, including Mr Litvinenko's home.

Agency staff will be contacting heath care workers involved in the direct care of Mr Litvinenko, as well as those who may have had very close contact with him when he was ill - including his family. This will involve a simple questionnaire and the provision of a urine sample if appropriate.

Professor Pat Troop , Chief Executive of the Health Protection Agency, said: "Normal hygiene and cleanliness practices in hospitals should have reduced the likelihood of any significant intake by NHS staff and others and therefore any radiation hazard.

"Nevertheless it is prudent to monitor as a precaution those people who came into direct and close contact with Mr Litvinenko to ensure there has been no cross contamination - Agency staff are meeting with these people urgently.

"Other people would not be exposed to radiation simply through being near to Mr Litvinenko. There would be a potential radiological hazard to people who could have ingested or breathed in the contaminated body fluids, but this hazard is likely to be restricted to those who have had very close contact with Mr Litvinenko."

1. What is polonium 210?

Polonium-210 (Po-210) is a radioactive material. It occurs naturally and is present in the environment and in people at very low concentrations. It can also be made by irradiation of other materials. Polonium-210 has a half-life of 138 days. It undergoes decay by emitting alpha particles, accompanied by very low intensity gamma rays. Alpha particles do not travel very far -- no more than a few centimetres in air. They are stopped by a sheet of paper or by the dead layer of outer skin on our bodies.

Polonium-210 is used industrially, for example in anti-static devices in factories.

Because polonium-210 is a naturally occurring radionuclide, we all have a very small amount in our bodies. This contributes to the natural radiation dose we all get every year.

2. How can polonium-210 harm people?

Because it emits alpha particles, Po-210 represents a radiation hazard if it is taken into the body - by inhalation, ingestion or through wound entry.

Since Po-210 only emits gamma rays very weakly, it is not a radiological hazard as long as it remains outside the body. If taken into the body, Po-210 is subsequently excreted, mostly through faeces but some is excreted through urine and other pathways. After uptake to blood, Po-210 is widely distributed though soft body tissues including bone marrow. The greatest amounts of polonium-210 are excreted in the first few days after intake.

The biological half-time (the time for the level of Po-210 in the body to fall by half) is approximately 50 days. Radiation doses, including those from polonium-210, are assumed to give rise to an increase in lifetime cancer risk. The larger the dose, the larger the risk. Very high radiation doses can cause damage to body tissues and organs and in the extreme can be fatal.

If anyone has been internally contaminated by inadvertently ingesting or inhaling polonium-210, it is most unlikely that they would receive a radiation dose high enough to give rise to medical symptoms.

3. The Health Protection Agency (HPA) is an independent body that protects the health and well-being of the population. The Agency plays a critical role in protecting people from infectious diseases and in preventing harm when hazards involving chemicals, poisons or radiation occur. We also prepare for new and emerging threats, such as a bio-terrorist attack or virulent new strain of disease.

4. Part of the Centre for Radiation, Chemical and Environmental Hazards, the Radiation Protection Division carries out the Health Protection Agency's work on ionising and non-ionising radiations. It undertakes research to advance knowledge about protection from the risks of these radiations; provides laboratory and technical services; runs training courses; provides expert information and has a significant advisory role in the UK .

http://www.hpa.org.uk

• Additional
• References
• Citations