Health risks kept under wraps in rush to transfer

They include a warren of 171 drift mines dug a century before homes were built, widespread tipping of asbestos waste slurry, old and unmarked rubbish dumps, and 300-year-old plague pits.

A paint factory next door to one transfer was found to have been a former 19th century tannery, which included a burial pit for animal carcasses with the consequent risk of deadly anthrax disease.

A new report by the Housing Corporation says problems like these often do not emerge until the last minute, as both landlords concentrate on meeting tight government deadlines.

It also suggests that housing associations and lenders are kept in the dark about the risks posed by potential hazards, no matter how slight, in case they jeopardise the transfer's value.

The corporation intends all future transfers to be subject to tight warranties, under which the council guarantees the transfer association and the lender that all information is about the property is correct.

National Housing Federation head of housing finance and new initiatives Stephen Duckworth said the revelations were particularly timely given the growing number of urban transfer proposals, which could involve properties originally built on brownfield sites.