National Organic Standards Board

Handling Subcommittee

Petitioned Material Discussion Document

Magnesium Carbonate Hydroxide

August 1, 2023

Summary of Petition [Magnesium carbonate hydroxide petition]:

This document reviews the petitioned use and addition of magnesium carbonate hydroxide as a 

processing aid to the National List at §205.605(): Nonagricultural (non-organic) substances allowed as 

ingredients in or on processed products labeled as “organic” or “made with organic (specified 

ingredients or food group(s)).”

Introduction: 

In December 2022, Leroux petitioned the United States Department of Agriculture (USDA) National 

Organic Program (NOP) to add magnesium carbonate hydroxide as a processing aid to the National List 

at §205.605(b). The Handling Subcommittee requested a Technical Report (TR), which is still in process. 

Therefore, the information presented in this discussion document is solely from the petition.

Relevant Background: 

Magnesium carbonate hydroxide has never been petitioned or included on the National List.

However, Leroux has also petitioned magnesium carbonate for the same use. Magnesium carbonate 

was previously listed at § 205.605(b) with the following annotation: “for use only in agricultural products 

labeled “made with organic (specified ingredients or food group(s)),” prohibited in agricultural products 

labeled “organic”.” (65 FR 80547, page 1708) 

In 2005, magnesium carbonate was petitioned for inclusion to the National List as a filtering aid at §

205.606. The petition was rejected by the NOP because it was incomplete, and this substance was 

ineligible to be added at § 205.606 as it is not agricultural.

During the sunset review process in 2015, the Board voted to remove magnesium carbonate from the 

National List stating, “the material does not appear to be essential to organic handling.” Magnesium 

carbonate was removed from the National List effective August 7, 2017. The final rule stated, “AMS 

received no public comments concerning the proposed removal of...magnesium carbonate from the 

National List.” (82 FR 31241, page 14) 

Use: 

Magnesium carbonate hydroxide is used as a drying agent/anti-caking agent. The petitioned use is 

focused on organic chicory production, specifically organic instant chicory powder. The petitioner notes 

that during the final steps of atomization and packing that the instant chicory powder sticks to the walls 

of the installations, requiring several stops for cleaning which reduces the rate of production.

The petition states, “The use of magnesium hydroxide carbonate as a processing aid is intended for the 

manufacture of the instant extract of chicory obtained by atomization. The incorporation of E504(ii) is 

done in the crown of air at the bottom of the tower feeding the dryer in order to obtain re-aeration and 

very good homogeneity of the product (figures 1 and 2). The maximum amount used would be 0.05%.” 

The petition includes several diagrams to pictorially represent the use of magnesium carbonate 

hydroxide in the production of organic instant chicory powder.

National Organic Standards Board (NOSB) Proposals and Discussion Documents October 2023 121/196
The petitioner also petitioned magnesium carbonate. These appear to be used interchangeably.

Summary of Review:

The Handling Subcommittee is waiting to receive the TR to fully evaluate the manufacturing process and 

review criteria for addition to the National List. However, the Subcommittee members did discuss the 

history of the related petitioned substance magnesium carbonate along with current alternatives. 

It appears that silicon dioxide is currently used as an alternative. However, the petitioner states that 

there have been some questions raised regarding the presence of nanotechnology in silicon dioxide. The 

NOP prohibits the use of nanotechnology (NOP Policy Memo 15-2), therefore the Subcommittee is 

unsure of the merit of this argument.

Questions:

1. Why are other substances listed on the National List as drying agents/anti-caking agents not 

effective for organic instant chicory powder?

2. Are there other organic products that would benefit from the use of magnesium carbonate

hydroxide for this use as a processing aid or should use be restricted as an anticaking agent only 

in instant chicory powder?

3. When listed previously magnesium carbonate was restricted for use in “made with organic” 

products only. If the NOSB recommends listing, should it consider limiting magnesium carbonate 

hydroxide for use only in “made with organic” products?

Vote in Subcommittee:

Motion to accept the discussion document on magnesium carbonate hydroxide.

Motion by: Kyla Smith

Seconded by: Dilip Nandwani

Yes: 8 No: 0 Abstain: 0 Recuse: 0 Absent: 1

National Organic Standards Board (NOSB) Proposals and Discussion Documents October 2023 122/196