It concluded that the tone of media reports on the subject underwent a "fundamental shift" in response to a high-profile incident in which Dr. Arpad Pusztai, a researcher for Rowett Research Institute, was fired after making a televised claim about detrimental health effects in lab rats fed a diet of genetically modified potatoes (see the Pusztai affair). Subsequent peer review and testimony by Dr. Pusztai led the House Science and Technology Select Committee to conclude that his initial claim was "contradicted by his own evidence." In the intervening period, Sainsbury's and Safeway both pledged that none of their house brand products would contain genetically modified ingredients.[7]