No traces of the food poisoning bug Yersinia was found in Foodstuffs Living Foods property and processing plant.
Foodstuffs has released the results of testing carried out at the location where its pre-packaged Pams lettuce is grown and packed.
The results showed no Yersinia pseudotuberculosis was detected in any samples.
"Multiple soil samples were taken from the quarantined paddock and across the farm, all of which failed to detect an evidence of Yersinia pseudotuberculosis," said Foodstuffs NZ spokeswoman Antoinette Shallue.
"In addition, samples of irrigation and processing water, and swabs from the processing plant and final product tests also failed to detect any presence of Yersinia pseudotuberculosis."