Fox Sports |
Newspapers |
CareerOne |
carsguide |
TrueLocal |
Real Estate |
MySpace AU
The Daily Telegraph - Home

Innocent chemical a killer

Article from: The Daily Telegraph

By Jeremy Manier

December 04, 2006 12:00am

THE suspected murder weapon is a substance found in nature and normally harmless, yet so toxic if swallowed that it can kill in doses smaller than a speck of dust.

The radiation it emits can't penetrate skin or paper, making it relatively safe to deal with and relatively easy to conceal.

Yet it can leave traces on surfaces it touches.

Eventually, the unusual properties of the radioactive element polonium-210 may be what allows authorities to trace the perpetrator of the lethal attack on a Russian ex-spy who died on November 23.

Amid international intrigue over the death of Alexander Litvinenko, the oddest factor may be the substance that killed him.

It has brought a reaction from the British Health Protection Agency that one paper has described as similar to the planned protocols for dealing with a "dirty bomb".

Polonium occurs naturally at low levels in ordinary soil and can be found in water, cigarettes and some vegetables. It has been used commercially in devices to eliminate static electricity. Most experts say it would take a nuclear reactor or particle accelerator to make significant quantities of the material.

The threat comes from alpha particles produced by radioactive decay. Polonium-210 decays rapidly; the isotope has a half-life of just 138 days.

Its decay also releases intense heat if the substance is present in large amounts. One gram can reach more than 900C, which is why the Russians used it as an energy source for space probes.

The alpha particles that polonium releases cannot penetrate a sheet of paper, but if ingested they can kill cells by breaking strands of DNA, said Albert Wiley, director of a radiation emergency response centre within the National Nuclear Security Administration.

"Before this incident I had never heard of polonium being used in a poisoning," he said.

One of the only previously suspected victims of polonium was scientist Irene Joliot-Curie, the daughter of researchers Marie and Pierre Curie, the co-discoverers of polonium. Joliot-Curie, a Nobel Prize winner like both of her parents, died of leukaemia 10 years after an accidental exposure to the substance.

When ingested, polonium-210 can damage the digestive tract and enter the bloodstream, where it can devastate bone marrow and vital organs. The isotope also can cause baldness because it damages hair follicles and any other tissue that undergoes a rapid turnover of cells, Wiley said.

Just one-millionth of a gram of polonium-210 could be a fatal dose, according to a fact sheet released by the Health Physics Society.

Choose your news

Have Your Say

We welcome your comments on this story. Comments are submitted for possible publication on the condition that they may be edited. Please provide your full name. We also require a working email address - not for publication, but for verification. The location field is optional. Read our publication guidelines.

Submit your feedback here:

right panel test

Take 40 music player
Tune in to the official Top 40 music videos and tracks. Take me there
Sydney Confidential
Join Australia's most renowned gossip columnists. Celeb news
Whether you follow NRL, Super 14, AFL or A-League, it's all here
The latest on banking, investments and super. Guides and tools
How much is your home worth? Check our Property Price Guide

Your say