All of the Fluffy homes would be contaminated with loose-fill asbestos, ranging from higher-than-background levels to extreme in some cases, the taskforce said. Loose-fill was a particularly dangerous form, and the situation was even worse for homes containing loss-fill crocidolite.

The asbestos was not only in roof spaces, wall cavities and subfloors, but was consistently penetrating living areas, with clear entry points even in homes in good condition.

In the most extreme cases, asbestos, including the even more dangerous crocidolite, had been found in visible quantities in cupboards, on top of refrigerators or microwaves, in heating and cooling systems and in bedding.

Tests had found the sealant used in the 1980s clean-up to bond fibres to roofs and trusses was deteriorating. Subfloor contamination was worse where there was a garage or storage area, and a number of families had remarked that they used the spaces "to store the Christmas tree, camping gear and the roll-away bed for guests". Contamination of soil was a significant concern.

There was no safe level of exposure to the carcinogen and the risk of disease increased with the intensity and time of exposure, the taskforce said. While asbestos diseases were rare even with significant exposure, if large numbers of people were exposed even to a low risk of disease, the risk increased that "one or more people will be affected".

"Perhaps the most telling response of all from licensed assessors to the current and future risks faced by residents in affected homes has been the numbers who have indicated they would not live in an affected house, nor raise their children in one," the report said.

The report, from taskforce head Andrew Kefford, will do little to allay the concerns of homeowners about whether they can keep belongings in the mass demolition. At the least, carpets and curtains should be disposed of as contaminated waste, he recommended. He was still developing an approach to deal with other contents, but it was impossible to rule out the presence of fibres in soft furnishings, linen and clothes, he said. Although clothing could be washed, there was no way to ensure it was free of fibres.

He raised the possibility that "all porous items such as carpets, and soft furnishings such as curtains, lounges, bedding and clothing may have to be removed and disposed of as asbestos contaminated waste", but also said that while furniture and other items were probably contaminated, the extent of contamination was likely to be low if they had not been stored in the roof or subfloor.

"Considerable distress could be caused by home occupants not being able to take potentially contaminated personal possessions when vacating a home," his report said, promising an approach that "focuses on safety but also practicality".

"Requiring destruction of all items would be distressing and potentially wasteful, but it is also possible that professional cleaning is not likely to be cost effective in some cases," he said.

Personal items with hard, wettable surfaces could be decontaminated by an asbestos removalist. But soft furnishings, toys, line and clothing could not be conclusively decontaminated in that way. Vacuum cleaners, washing machines and dryers could not be remediated.

Mr Kefford said demolition of homes was the only lasting solution. Any attempt to clean or make homes safe would leave fibres behind, risking the health of residents, tradespeople and visitors, and would also leave a stigma attached to the houses. While houses could with considerable effort be made safe to live in in the short to medium term, it would "require a level of restriction of the normal use of a property, vigilance and ongoing assessment and remediation that would be economically and socially unsustainable".

Doing nothing was not an option, and demolition while "a very significant, costly, logistically challenging and emotionally traumatic approach", was the only enduring solution.

Mr Kefford's report acknowledged the "enormous reluctance and sadness" with which owners would receive the news, but said "with eyes wide open about how hard that will be for affected families and for the broader community, it is time to move on".