Some people have suffered burns from the fungicide
The UK's largest group action for consumer injury is to be brought for people who claim they have been burnt by toxic sofas, their lawyers said.
More than 5,000 people have reported skin, chest and eye problems after buying leather sofas sold by Land of Leather, Walmsleys and Argos.
The furniture, from China, is thought to contain a chemical which can cause burns and may be linked to some deaths.
Argos said it made recalls, Walmsleys and Land of Leather gave refunds.
As well as recalling about 30,000 sofas they had sold, Argos also said it had refunded customers.
Walmsleys and Land of Leather said they gave refunds to those who had complained but had not recalled their stock.
A hearing will be held at the High Court in February to establish which sofas were faulty and what level of damages should be awarded to victims.
Lawyer Richard Langton, from Russell, Jones and Walker, said his firm was initially only dealing with around 2,000 customers, but after a media appeal, a further 3,000 people came forward who had not known of a possible link between their injuries and their sofa.
People say they have developed blisters on their legs and back
The firm said liability under the Consumer Protection Act and Sale of Goods Act had been accepted for dozens of models sold by the three outlets.
The furniture was made by Chinese companies Linkwise and Eurosofa and other manufacturers' products are now being tested for fungicide Dimethyl Fumarate (DMF).
Authorities in France banned products containing DMF following a similar outbreak and the group's law firm are calling on the British government to follow suit.
Mr Langton said: "Thousands of people have already suffered a painful allergic reaction to their sofa because of inadequate safeguards.
"The warning issued by BERR [department of Business, Enterprise, and Regulatory Reform] in October 2007... was inadequate as it didn't name the manufacturer and there has been absolutely no action to investigate the problem further or stop imports of contaminated goods to the UK.
"In France, within weeks of the outbreak being identified, all imports have been banned.
Nothing we were doing was making her batter
Mel Hackworth, mother
"A voluntary system is clearly not enough because it is impossible to tell whether a product has been treated with DMF until the user develops a painful dermatitis."
Trading Standards said they had not ordered a recall because they could not gather enough evidence from scientists to prove the sofas were the source of the rashes.
Mel Hackworth's one-year-old daughter developed a painful rash on her legs at the same time as the family's new sofa arrived, and doctors were at a loss over what to do.
Mrs Hackworth told the BBC: "It was just awful. You try to protect your children, you try to make your children better and nothing we were doing was making her better."
Dr Sandra Winhoven told the BBC: "The substance that's causing the sofa dermatitis outbreak is a fungicide and the fungicide has a very low vapour point, which means it goes into the air at a low temperature.
"There is a worry that with the summer months we will see an increased number of people with the problem."
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