Both the Construction Confederation and the Construction Industry Council have responded to the London mayor's comments on the health and safety and environmental records of contractors Balfour Beatty, Jarvis and Mowlem.
Construction Confederation chief executive Jennie Price described his claims as extreme and inaccurate.
She said: "It's a great shame that Ken has chosen to condemn out of hand companies that have played such a vital role in the capital's infrastructure."
Construction Industry Council chief executive Graham Watts said Livingstone's comments were "completely over the top" and questioned his attack on Mowlem's record of roadbuilding.
He said: "If contractors are scum for building roads, then what are Prescott and Brown for introducing a 10-year plan to build more roads?
"Livingstone is hardly going to endear himself to Londoners that work in the industry. We're not above criticism in some of these areas but he has gone completely over the top. Does parliamentary immunity extend to the office of London mayor?"
A spokesperson for construction minister Nick Raynsford said he could not comment on the speech while the Tube bidding process was still in progress.
Construction Confederation president and Mowlem chief executive John Gains was not available for comment. However, a Mowlem spokesperson pointed to the company's record in completing London's Docklands Light Railway extension two months early.
He said: "That's an example of Mowlem offering infrastructure solutions to London and London benefiting from them. Who could claim any more than that?"
Livingstone made his comments at a rally of Transport & General Workers Union members. He singled out Jarvis because of its allegedly poor health and safety record and Balfour Beatty and Mowlem for their environmental records.
A spokesperson for the Greater London Authority said it had asked a Manchester company, Ethical Consumer Research Association, to look into the backgrounds of the firms involved in the Tube bids.
The spokesperson said: "We stand by everything the mayor said.
The GLA is opposed to the part-privatisation on the grounds of safety and cost. We are not part of the selection process for the Tube bids and as such we are keen to find out as much information about the companies and contractors involved as we can."
The spokesperson added that Livingstone was not available for comment and would be on holiday for the next fortnight.
