"The FDA collected 504 romaine samples for EHECs and Salmonella spp., with the testing performed by an independent laboratory on contract, as part of a pilot project. Each sample consisted of 10 subsamples, and each subsample was made up of at least 300 grams of romaine lettuce (whole heads, hearts or individual leaves)."
"During the assignment the FDA detected E. coli O130:H11 in one sample. The isolate was found to be moderate to high risk and could be capable of causing severe illness in humans, though it was not linked to any known human illnesses, and no product ever reached consumers. The owner of the product did not harvest the remaining crop from the field where it was grown."
"During the assignment the FDA detected E. coli O130:H11 in one sample. The isolate was found to be moderate to high risk and could be capable of causing severe illness in humans, though it was not linked to any known human illnesses, and no product ever reached consumers. The owner of the product did not harvest the remaining crop from the field where it was grown."
"In response to the finding, FDA conducted an investigation at the farm to identify possible sources and routes of contamination. The FDA was able to collect romaine lettuce from the field, multiple samples of soil, water, sediment, and animal fecal material. FDA also assessed farm equipment and other surfaces. Only one of the total 24 samples yielded STEC (specifically, E. coli O116:H-[which is different than the what was found in the initial sample]). This sample came from the outer leaves of romaine lettuce. The strain was further characterized as low risk to human health, and FDA’s analysis indicated the strain was not linked with any past known foodborne illness outbreaks."
This demonstrates the low level of pathogenic E. coli can be present and the difficulty in being able to find through sampling.
https://www.fda.gov/food/cfsan-constituent-updates/fda-releases-report-findings-sampling-romaine-lettuce-yuma-az
FDA Releases Report on Findings from Sampling of Romaine Lettuce in Yuma, AZ
Constituent Update
October 7, 2021
https://www.fda.gov/food/cfsan-constituent-updates/fda-releases-report-findings-sampling-romaine-lettuce-yuma-az
FDA Releases Report on Findings from Sampling of Romaine Lettuce in Yuma, AZ
Constituent Update
October 7, 2021