HALIFAX — All four of Canada's newly leased submarines contain varying amounts of asbestos insulation, a fact that caused concern for the navy as it grappled with the fallout from the deadly fire aboard HMCS Chicoutimi.

A briefing note to the chief of defence staff, written five days after the fire and obtained under the Access to Information Act, says the navy was worried about the "toxicity levels of cables (and the) extent of asbestos onboard.''

As with any electrical fire, the accident that crippled the warship last fall produced a cocktail of noxious smoke and gases.

One crew member, 32-year-old Lieut. Chris Saunders, died of smoke inhalation following the Oct. 5 fire off the coast of Ireland. Eight others were injured.

However, a spokesman for the commander of the navy, said it was too early to draw any conclusions, given that a military board of inquiry has yet to complete its work.

"A lot of the stuff that's around us -- the plastics, the adhesives, the paint and asbestos -- present a risk to any vessel,'' Maj. Tony White said in an interview.

"To suggest that asbestos was one of the components that burned in the Chicoutimi fire is pure speculation until the board has presented its analysis.''

The navy has stressed there was no indication the fire-resistant material was disturbed by the fire, which broke out during the sub's maiden voyage to Halifax.

As well, the mere presence of asbestos is no cause for alarm because the material only becomes a threat to health when it is damaged and its fibres can be inhaled or ingested.

The once-popular insulation, which was largely phased out in the 1980s because of links to cancer, was installed on a variety of systems on the British-built submarines, said Elizabeth Hodges, a spokeswoman for the Defence Department.

As an example, Hodges said various gaskets are made from asbestos.

"It would be used in high temperatures areas, such as diesel exhaust,'' she said.

Asbestos was commonly used in ships and the submarines were already under construction in Britain when the material was deemed unsafe, said Hodges.

Asbestos insulation has been linked to several forms of cancer, including mesothelioma, according Health Canada.

Mesothelioma is cancer of the lining of the lungs and also the lining of the abdomen.

Exposure to the fibres can also lead to asbestosis -- a non-cancerous disease that may not produce symptoms for up to 30 years.

As part of its reaction to the fire, the navy drafted a medical plan for the crew, according to heavily censored documents obtained by The Canadian Press.

A medical specialist was made available to "address any lasting or new general medical concerns following their ordeal,'' said the navy's plan, written on Oct. 24, 2004.

It is widely believed the fire aboard Chicoutimi started when sea water entered two open hatches and splashed on some high-voltage lines, causing a short circuit and a shower of sparks.

Canada's entire, glitch-filled submarine program has ground a halt as a navy board conducts an investigation and the Commons defence committee reviews the controversial purchase of the used warships.

The asbestos was first discovered on a hazardous materials list prepared by the British Ministry of Defence when the first of the four mothballed submarines was reactivated, said Hodges.

As improvements were made to specific parts, the insulation was ripped out and replaced with a less harmful products, she said.

"And during any follow on work done in Canada, asbestos parts are being replaced with non-asbestos parts, as needed.''

Sailors who witnessed the refit in Britain said they were routinely "warned to stay away from the boats when the stuff'' was being ripped out.

"Crews would get dressed up in suits and most of it would be done at night,'' said one member of the navy who asked not to be named.

Among the Canadian navy members assisting in the handover of the boats, there was virtually no discussion about the insulation.

"It was kind of spooky because nobody talked about this as a health hazard,'' said the source.