By Anna Edney | Updated on Jun 11, 2026 at 06:57 PM
Federal inspectors found no evidence that ByHeart Inc.’s infant formula production process caused a botulism outbreak that sickened dozens of babies, according to a new report that pointed to contaminated ingredients as a more likely culprit.
The inspection report posted Thursday by the US Food and Drug Administration examined the Iowa factory where ByHeart’s formula was made. The report said it’s more likely raw ingredients were the source of the outbreak than the manufacturing equipment and storage practices of the Blendhouse facility in Allerton, Iowa.
The outbreak discovered last year led to 48 babies hospitalized with confirmed or suspected botulism. None of the infants died, though botulism can lead to lasting complications. ByHeart recalled all of its formula in November and shut down production during the outbreak investigation. ByHeart, which said it makes formula with organic ingredients that closely mimic breast milk, made up about 1% of all infant formula sold in the US, the FDA has said.
The outbreak followed a 2022 shortage tied to Abbott Laboratories and shook confidence in the formula supply chain. Testing previously identified spores that can form botulism in a whole milk powder at a ByHeart supplier. The prior tests also found links between samples from one of the infants involved in the outbreak and the whole milk powder.
The new report detailed the findings of FDA inspectors from Nov. 11 to Jan. 22. Inspectors also visited Blendhouse’s Portland, Oregon, facility where the formula was canned and did not find any violations that might link it to the outbreak, according to a separate report.
ByHeart called the reports a milestone that will pave the way for restarting production “pending final alignment with the FDA,” a ByHeart representative said in an email.
The company has developed a new protocol to test for the spores that can form botulism “that will be applied to every dairy ingredient and to finished batches before they are released from our facilities,” according to the email.
“While we do not yet have a specific date for implementing this test we are working diligently toward that goal,” ByHeart said.