In an August 3, 2013, Washington Post article, writer Kimberly Kindy suggested that some of the chemicals—notably cetylpyridinium chloride (CPC), a purportedly common finishing rinse—used in U.S. poultry processing plants may be masking the presence of Salmonella and other pathogens that remain on the birds that are sold to consumers. Titled “USDA Reviews Whether Bacteria-Killing Chemicals are Masking Salmonella,” Kindy reports that academic researchers agree that “the chemicals could be overwhelming an antiquated testing process,” and she states that several of the scientists have been enlisted by U.S. Department of Agriculture food safety experts to investigate the matter.

At issue, Kindy contends, is whether CPC, or other antimicrobials, might remain on the samples collected for pathogen testing at a high enough concentration to kill the bacteria on the way to the lab. If so, Food Safety and Inspection Service experts could perceive a false negative test result when the chicken may actually be contaminated. This could explain why government data show significant reductions in Salmonella rates in poultry plants while the number of people getting sick from Salmonella in poultry appears to have stayed the same.