Two large egg producers have received warning letters from the Food and Drug Administration, which said they violated a two-year-old rule aimed at preventing salmonella contamination.
During inspections conducted last summer, the F.D.A. found failures to prevent pests and wildlife from entering barns housing laying hens, poor record-keeping and other infractions that amounted to what it called “serious violations” of the rule.
The failures meant that eggs the companies produced “may have become contaminated with filth,” agency inspectors wrote in the letters, which were sent late last month and posted on the agency’s Web site on Thursday.
The letters offer a window into the way new regulations the agency proposed last week to enhance food safety might work. The proposed regulations, like the rule cited in the letters, aim to prevent food from being tainted rather than addressing contamination after it has occurred.