# Safety and efficacy of a feed additive consisting of l‐threonine produced with Escherichia coli CCTCC M 2024477 for all animal species (Kempex Holland B.V.)

## TL;DR

This paper evaluates the safety and effectiveness of a genetically modified l-threonine feed additive for all animal species.

## Contribution

The study confirms the safety of a genetically modified E. coli-produced l-threonine additive for animal feed and consumer use.

## Key findings

- The l-threonine additive is safe for target species when used appropriately.
- The additive is effective as a source of l-threonine for non-ruminant animals.
- The additive is safe for consumers and the environment.

## Abstract

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of the feed additive consisting of l‐threonine produced by fermentation with Escherichia coli CCTCC M 2024477 when used as a nutritional additive in feed and water for drinking for all animal species and categories. The production strain is genetically modified. None of the genetic modifications raised a safety concern. Viable cells or DNA of the production strain were not detected in the final product. The use of l‐threonine produced with E. coli CCTCC M 2024477 in feed is safe for the target species when supplemented in appropriate amounts to the diet according to their nutritional needs. The FEEDAP Panel has concerns on the use of amino acids in water for drinking. The use of l‐threonine (≥ 98.0%) produced with E. coli CCTCC M 2024477 in animal nutrition is considered safe for the consumers and the environment. Regarding the user safety, the FEEDAP Panel cannot conclude on the potential of the additive to be irritant to skin and/or eyes and to be a potential skin sensitiser. The FEEDAP Panel considers that the exposure of the users to bacterial endotoxins should be minimised. Any exposure to the additive is a risk. The additive is regarded as an effective source of the amino acid l‐threonine for all non‐ruminant species. To be as efficacious in ruminants as in non‐ruminants, it should be protected from ruminal degradation.