A former employee of the soft drinks giant, Coca-Cola, has filed a US$44.4m lawsuit against the company, alleging that it failed to act on claims of product contamination.

Matthew Whitley, who was a member of the company's internal auditing team, has alleged that he was laid off for being a "whistle-blower".

Coca-Cola has dismissed the suit, filed in Atlanta's Fulton County Superior Court, as the act of a "disgruntled former employee", but said an external audit was being carried out by Deloitte & Touche into the allegations. The company would not comment of the details of the allegations. "Until the investigation is complete, we cannot have a basis to respond to these allegations," the company said.

Whitley said he had brought to the company's attention certain problems, including the contamination of a Coca-Cola's frozen ice drinks with metal residue but the company had taken no action. Whitley said six weeks later he received his worst ever performance review and was subsequently laid off as part of a larger redundancy programme.

Whitley is also alleging that Coke engaged in deceptive marketing and accounting practices.