Giving terrorists ideas

Last December, I noted how the use of polonium in the Litvinenko murder in London had raised concerns about how this very dangerous substance could be used to create a really devastating dirty bomb.

Security experts are still worrying about this:

The authors call such methods I3, for inhalation, ingestion and immersion. One of the writers, Peter Zimmerman, a nuclear physicist, said yesterday that a well-planned radiological attack "would be capable of killing several hundred, maybe upwards of a thousand, and paralysing a city without any question at all."

The article does not provide details of the most devastating method of attack the authors have conceived, for security reasons, but Professor Zimmerman described one scenario using a water-soluble radioactive isotope widely used in hospitals and industry: "I can then tap into the anti-fire spray in a theatre, and if I can trigger the spray, I can soak everyone in the room."

Polonium-210, which was used in Mr Litvinenko's murder, is even more deadly because it emits alpha radiation, which is not picked up by radiation sensors.

It's a worry.