Silvercrest Foods, Ireland’s second largest producer of beef burgers, has recalled 10 million burgers following the discovery of varying levels of horse meat in the company’s patties. DNA testing by Ireland’s Food Safety Authority showed trace levels of horse meat in around one third of burgers, and turned up a surprising 29 percent horse meat in one burger out of 27. Tesco, the British supermarket that sold the burgers, apologized and said fraud or incompetence was to blame. Silvercrest said it suspects the contamination came via a powdered beef-protein additive used to fill out the cheaper burgers. Ireland’s DNA testing policy goes beyond most country’s food safety standards, and health authorities suggested that were such testing carried out worldwide, many more contaminated samples would be discovered.