A secret intelligence report distributed to key federal authorities by the Privy Council Office expresses concern that al-Qaida extremists could use lethal substances such as ricin and botulinum in a terrorist campaign.

A declassified version of the document was obtained by The Canadian Press under the Access to Information Act.

Toxins, some more powerful than the strongest nerve agents, can be made from a variety of readily available plants, fungus, bacteria or animals, the report says.

"They have considerable potential as terrorist weapons for isolated incidents causing small-scale casualties along with public panic and disruption."

The February 2003 report, Ricin and Botulinum: Terrorist Use of Toxins, was compiled by the PCO's intelligence assessment secretariat, a division bolstered following the Sept. 11, 2001, attacks on the United States by Osama bin Laden's al-Qaida network.

The study was prompted by the discovery last January of ricin, a plant toxin made from castor beans, in a London apartment, as well as the retrieval last year of al-Qaida training manuals on the production and use of toxins.

The report by PCO, the prime minister's top advisory body, was distributed to senior security officials at federal organizations including the RCMP, CSIS, Health, Defence, Immigration, Foreign Affairs and the Canadian Food Inspection Agency.

Several portions of the document, notably a section entitled Implications for Canada, were withheld under provisions of the access law pertaining to international affairs and security.

"Toxins are among the most poisonous substances known to man, and ricin and botulinum are among the most virulent toxins available to terrorists," the report says.

Toxins are not contagious, meaning potential victims must be directly exposed.

Terrorist attacks with ricin would likely involve contamination of food or water, or dissemination as an aerosol, says the report. Even small quantities of ricin powder can shut down protein synthesis in the body, causing death within days.

"Ricin is water-soluble, and water supplies can therefore remain contaminated for a considerable length of time," the report notes.

Ricin, first turned into a weapon by the U.S. during the Second World War, has been smeared on doorknobs - and in one case on the tip of an umbrella - in assassination attempts carried out by spies and extremists.

Iraq admitted manufacturing ricin and field-testing it in artillery shells before the Persian Gulf War, the document says.

Last April, the federal government hired Winnipeg-based Cangene Corp. and Twinstrand Therapeutics of Burnaby, B.C., to jointly develop antibody-based therapies for people exposed to ricin. Currently, there is no antidote.

The report notes highly toxic botulinum occurs naturally when food or other material is contaminated by the bacteria clostridia, "and like ricin it can be produced by terrorist organizations using relatively rudimentary techniques."

However, exposure can be treated.

Botulinum was used by Japan during the Second World War. In the 1990s, Japanese terrorist group Aum Shin Rikyo unleashed the deadly substance as a spray in at least four attacks.

According to a 1999 United Nations report, Iraq produced some 380,000 litres of botulinum before the Gulf War and acknowledged arming at least 100 warheads with it.

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