Ricin bomb: al-Qaeda’s revenge for bin Laden?

According to 'unnamed sources' leaking to the New York Times, which is close to the Obama administration, al-Qaeda in the Arabian Peninsula (AQAP) is currently trying to develop a 'dirty bomb', with a twist, from its mountain fastness in Yemen. 

Packed around the explosives would be quantities of the poison ricin, made from the widely available castor oil plant. The president has apparently been briefed on a number of occasions about the threat, thought to be a work in progress rather than imminent.

They are right to be worried. Ricin is nasty stuff. A dose as small as a few grains of salt or sugar, if inhaled or injected, leads to a horrible and drawn out death by suffocation or organ failure. If swallowed, a bigger dose is needed and you are in with more of a chance - but not much more. It takes three to five days to die. There is no antidote.  

The bad news is that there isn't much the doctors can do except put you on life support and hope for the best. The good news is that if you are not dead by the fifth day, you will probably make it.

The even worse news is that the chemistry behind it is simple. If you know how to mash an avocado and dry herbs in the sun you can make ricin from castor oil beans.

The most famous victim of the poison was the Bulgarian dissident Georgi Markov murdered in 1978 on Waterloo Bridge by Bulgarian secret policemen.

They shot a tiny ricin pellet into his leg using an air gun concealed in an umbrella. He hardly felt it, but died in distressing circumstances in hospital a few days later. It was nearly the perfect murder, but Markov's family became suspicious, as did Scotland Yard, who called in scientists from the chemical weapons establishment at Porton Down in Wiltshire. A painstaking post mortem revealed the tiny pellet. 

It later emerged that another Bulgarian dissident avoided a similar fate in Paris a few weeks earlier when a similar ricin pellet shattered while passing through his very chunky woollen jumper.  

Strangely, ricin has in various guises been a part of American life for nearly a century. US scientists considered using it in munitions in both the First and Second World Wars, ultimately in the late 1940s opting for the nerve gas sarin instead.

It also crops up from time to time in American detective fiction, most famously in one of Margaret Truman's excellent novels, set against the background of official Washington. Brought up in the White House when her father Harry Truman was president, her books have an extraordinarily authentic feel as a result. Although she was stretching it with Murder on Embassy Row in which the British ambassador of the day dies after a late night snack of Ricin-laced... caviar. 

In the real world of today the American intelligence establishment has been worried ever since they killed Osama Bin Laden on May 2 that al-Qaeda or one of its off-shoots would try to organise a spectacular revenge on American soil. The Taliban in Afghanistan have already got lucky by shooting down a Chinook helicopter ferrying US special forces to a remote valley north of Kabul.

AQAP in Yemen are resourceful, imaginative and determined. They were the brains behind the Christmas Day 2009 'underpants' bomb on Northwest Airlines Flight 253 to Detroit, and the October 2010 cargo plane bomb plot. The CIA believes that the AQ banner has now been passed to them and regards them as more of a threat to the US homeland than their parent organisation. US military and intelligence resources, operating from carriers at sea and French bases in nearby Djibouti, are being poured into the area.

Sadly, it's not just an American problem. At least 20 British Islamists, probably more, are believed to have travelled to Yemen in the last year alone for training and indoctrination. Which would account for the strong rumours that the SAS have returned to the Yemeni mountains where they last operated in the 1970s. ·