Sodium hydroxide

In the current application authorisation is sought under articles 4(1) and 10(2) for sodium hydroxide (E524) under the category/functional group 1(j) 'technological additives' / 'acidity regulators: substances which adjust the pH of feedingstuffs', according to the classification system of Annex I of Regulation (EC) No 1831/2003. Specifically, the authorisation is sought for the use of the feed additive for cats, dogs and ornamental fish.

The feed additive is a white solid substance, containing a minimum of 98% of sodium hydroxide. The Applicant states that the purity criteria set in Commission Directive 2008/84/EC and in Commission Regulation EU/231/2012 for the food additive are applicable for the feed additive. 

The feed additive is intended to be incorporated to feedingstuffs through premixtures, with no recommended minimum or maximum concentration levels. However, the Applicant suggested a typical inclusion level varying from 50 to 1000 mg sodium /kg feedingstuffs.

For the determination of sodium hydroxide in the feed additive, the Applicant proposed the internationally recognised FAO JECFA monographs for food additives, where: identification is based on the following tests: alkalinity, sodium and solubility in water/ethanol, while quantification is based on a titrimetric method. Even though no performance characteristics are provided, the EURL recommends for official control the methods described in the FAO JECFA monographs - as recommended by Commission Directive 2008/84/EC and by Commission Regulation EU/231/2012 - to determine sodium hydroxide in the feed additive. 

The Applicant did not provide any analytical method for the determination of sodium hydroxide in premixtures and feedingstuffs as the unambiguous determination of sodium hydroxide in these matrices is not achievable experimentally. Therefore, the EURL could not evaluate nor recommend any method for official control to determine sodium hydroxide in premixtures and feedingstuffs.

Further testing or validation of the methods to be performed through the consortium of National Reference Laboratories as specified by article 10 (Commission Regulation (EC) No 378/2005) is not considered necessary.

Recommended Method

as of:

- Commission Implementing Regulation (EU) 2024/1193

Determination of sodium hydroxide in feed additive: 

• Titrimetry — FAO JECFA Combined Compendium for Food Additive Specifications, Monograph No 1 (2006) ‘sodium hydroxide’