FDA testing identified botulism bacteria in an organic whole milk powder sample that matches the strain from a finished ByHeart formula and from a sick baby, though investigators are still tracing the exact contamination source.

Dairy Farmers of America runs a Fallon plant that processes about 1.5 million pounds of raw milk daily into 250,000 pounds of whole milk powder, with Organic West supplying milk from 55 farmers.

Dairy Farmers of America confirmed Organic West as the source of the milk for the positive powder and said the powder met all required tests, while Organic West halted sales of milk powder intended for babies and children pending investigation.

Authorities stress ongoing cooperation to pinpoint the contamination pathway and to ensure product safety.

This outbreak is the first large-scale botulism incident linked to infant formula, though botulism spores have appeared in infant formula before and routine botulism testing in formula is not mandatory.

Officials note botulism in infant formula is rare, but this event has intensified scrutiny of formula safety and supply-chain handling as the first major outbreak tied to the product.

Experts explain that botulism spores are common in the environment and can be present in milk, with pasteurization not killing spores, making infants particularly vulnerable due to immature gut flora.

Botulism spores can be present in the environment and milk; pasteurization does not kill spores, and contamination can occur in the processing environment or during production of powder used for infant formula.

Health experts emphasize that pasteurization does not eliminate spores and that babies are especially at risk because their gut flora are immature, which can allow spores to germinate and produce toxin.

Given the environment and milk source risks, spores can be present in products used for infant formula, underscoring why contamination is a critical concern for makers and regulators.