Marine Magnesium Hydroxide With 5% Corn Starch Classifiable Under Tariff 28161010: CAAR Mumbai

In re Inhalation Health Private Limited (CAAR Mumbai)

Summary: The Customs Authority for Advance Rulings (CAAR), Mumbai, considered an application by Inhalation Health Private Limited concerning the customs classification of “Aquamin Mg TG”, a marine-derived magnesium hydroxide product proposed to be imported from Ireland. The applicant sought confirmation that the product was classifiable under Customs Tariff Item 28161010 of the First Schedule to the Customs Tariff Act, 1975. The ruling was delivered on 29 October 2026 after examining the applicant’s submissions, technical documents, manufacturing process and relevant tariff provisions.

The applicant explained that Aquamin Mg TG contained approximately 95% marine magnesium hydroxide and not more than 5% corn starch. Magnesium hydroxide was derived from seawater, while corn starch was introduced during manufacturing as an anti-caking agent to improve handling and powder flowability. The applicant maintained that the residual naturally occurring marine minerals were incidental constituents of the starting material rather than intentionally added ingredients. It submitted a safety data sheet, manufacturing-process flowchart and supplier’s composition statement to substantiate the product’s composition and manufacturing process.

The principal issue was whether the presence of corn starch and naturally occurring trace minerals prevented classification under Chapter 28, which generally covers separate chemically defined inorganic compounds. The Authority examined General Rule for Interpretation 1, Chapter Note 1(a) and 1(d) to Chapter 28, and the relevant HSN Explanatory Notes. It considered whether the residual minerals qualified as permissible impurities and whether the added corn starch was an acceptable anti-caking agent that preserved the product’s essential character as magnesium hydroxide.

The Authority found that the product’s principal constituent was magnesium hydroxide and that the naturally occurring trace minerals were residual constituents associated with its seawater-derived manufacturing process. It accepted that the corn starch served an anti-caking function related to physical handling and powder flow, without altering the essential chemical character of the product. On that basis, the Authority held that the product satisfied the relevant Chapter 28 conditions, including the treatment of permissible impurities and anti-caking agents under the applicable Chapter Notes and HSN Explanatory Notes.

The Authority ruled that Aquamin Mg TG is classifiable under Customs Tariff Item 28161010 (Hydroxide of Magnesium), subject to the imported product conforming to the composition, manufacturing process and functions of its constituents described in the application and supporting documents.

FULL TEXT OF THE ORDER OF CUSTOMS AUTHORITY OF ADVANCE RULING, MUMBAI

M/s Inhalation Health Private Limited (IEC: AAFCI2104K) (hereinafter referred to as “the applicant”) has filed an application in Form CAAR-1 before the Customs Authority for Advance Rulings, Mumbai (hereinafter referred to as “CAAR” or “the Authority”). The application, along with the prescribed fee and supporting documents, was received in the Secretariat of CAAR, Mumbai on 29.07.2026 in terms of Section 281-1 (1) of the Customs Act, 1962. The applicant has sought an advance ruling under Section 2814 (2) of the Customs Act, 1962 on question relating to the classification of the product described as “Aquamin Mg TG”.
2. Applicant’s eligibility for Advance Ruling:

The applicant holds a valid IEC No. AAFCI2104K and therefore qualifies as an “applicant” under Section 28E(c) of the Customs Act’ 1962. The question on which the advance ruling is sought is in respect of classification of goods under the Customs Tariff Act’ 1975 which is admissible under Section 28I 1(2)(a). The applicant has declared that the questions raised in the present application is not pending in the applicant’s own case before any officer of customs, the appellate tribunal, or any Court and is not a matter already decided by the appellate tribunal or any court. Accordingly, the application appears admissible under Section 28-1 of the Customs Act, 1962.

3. Ouestion(s) on which Advance Ruling is required:
Question 1. Whether the product i.e., “Aquamin Mg TG” in the present application is classification under Tariff Item 28161010 of the First Schedule to the Customs Tariff Act, 1975?

4. Submission by Applicant-
Statement of the relevant facts having a bearing on the question(s) on which the advance ruling is required

4.1 The Applicant is a private limited company and is engages in the activity of import and trading of various goods.

4.2 The Applicant proposes to import “Aquamin Mg TG” Manufactured by Superior Powders Ltd UK and supplied by Marigot Ltd — Ireland.

4.3 The said product has the following composition:

4.4 The Applicant has submitted the Safety Data Sheet of the subject product.

4.7 Magnesium Hydroxide is an Inorganic Compound, which is represented by the chemical formula — Mg(O1-I)2. Since Magnesium Hydroxide has a definite Chemical/Molecular Formula and can therefore be represented by a definitive structural diagram, it is a Separate chemically defined compound.

4.8 As is evident from the Process Flow Diagram, the starting material for the manufacture of Aquamin Mg TG is Magnesium Oxide derived from seawater. Such Magnesium Oxide is subjected to an exothermic reaction with water to obtain Magnesium hydroxide, which, as stated herein above, is a separate chemically defined compound. Thereafter, Corn Starch is incorporated during manufacture solely as a processing aid to improve the handling and powder flowability of the Magnesium I lydroxide.

4.9 Since the starting material is Magnesium Oxide derived from seawater, naturally occurring marine trace minerals present in the seawater remain in the final product and cannot he removed through the manufacturing process. Such trace minerals are neither intentionally added not deliberately retained, but remain present in the finished product only in trace quantities as naturally occurring residual constituents originating from the seawater derived starting material.

4.10 By the present Application, the Applicant seeks advance ruling on Customs Tariff classification of the said product, “Aquamin Mg TG” proposed to be imported by the applicant.

Statement containing the applicant’s interpretation of law and/or facts, as the case may be, in respect of the questions(s) on which advance ruling is required:

4.11 It is the Applicant’s interpretation that, as explained herein after, the said goods will fall under Heading 281610 under the description “Hydroxide and Peroxide of Magnesium”. Under Heading 281610, it will fall under Sub-heading 28161010 which covers “Hydroxide of Magnesium”.

4.12 Since Aquamin Mg TG consists of 95% or above of Marine Magnesium Hydroxide, it is appropriately classifiable under Sub-heading 28161010, which covers “Hydroxide of Magnesium”. Magnesium Hydroxide is an inorganic compound represented by the chemical formula Mg(0I1)2. Since Magnesium I-hydroxide has a definite chemical/molecular formula and can therefore be represented by a definitive structural diagram, it is a separate chemically defined compound’ and therefore satisfies the requirements of Note 1(a) of Chapter 28. The naturally occurring marine trace minerals present in the product originate from Magnesium Oxide derived from seawater, which is used as the starting material, and remain present only in trace quantities. Such trace minerals are neither intentionally added not deliberately retained during manufacture and cannot he removed through the normal manufacturing process. As evident from the HSN Explanatory Notes to Chapter 28, the presence of such naturally occurring residual constituents does not affect the classification of the product under Chapter 28. Further, Corn Starch (5% or less) is incorporated during manufacture solely as a processing aid to improve powder flowability and handling characteristics. The addition of such processing aid also does not affect the classification of the product under Chapter 28, as evident form the IISN Explanatory Notes.

4.13 The Applicant therefore prays for Advance ruling that the said product “Aquamin Mg TG” discussed herein above, is correctly classifiable under Customs Thrill Sub-heading 28161010.

5. Port of Import and reply from jurisdictional Commissionerate:

The applicant in their CAAR-1 indicated that they intend to import the subject goods at the jurisdiction of Office of the Commissioner of Customs, NS-I, .INCI I, Nhava Sheva, Uran, Raigad, Maharashtra – 400707. Accordingly, the application was forwarded to the concerned jurisdictional Commissionerate for furnishing their comments vide letter dated 17.08.2026. However, no comments have been received from the jurisdiction Commissionerate till dated.

6. Details of Personal Hearing: A personal hearing in the matter was held on 10.09.2026. The authorised representative/Advocate of the Applicant appeared and submitted that the product Aquamin Mg TG is basically a sea water extract consisting more than 5% Marine Magnesium Hydroxide and Corn starch, used as an anticaking agent, constituting less than 5% of the product. Therefore, they requested that the subject product to be classified under CTH 28161010.

6.1 Nobody appeared for the PI I from the Department.

7. Discussion and Findings
7.1 I have carefully examined the application filed by the Applicant, the statement of facts, the product composition, the Safety Data Sheet, the process flow diagram, the supplier’s statement and the submissions made during the personal hearing held on 10.09.2026. I have also examined the relevant provisions of the Customs Tariff Act, 1975, the General Rules for the Interpretation of the Import Tariff and the relevant Section Notes, Chapter Notes and I ISN Explanatory Notes. The issue for determination is whether the product “Aquamin Mg TG”, proposed to be imported by the Applicant, is correctly classification under Tariff item 28161010 of the First Schedule to the Customs Act, 1975.

7.2 The Applicant has stated that subject product i.e. Aquamin Mg ‘1’6 comprises of 95% or more marine magnesium hydroxide, while corn starch constitutes 5% or less of the product. According to the Applicant, magnesium hydroxide is manufactured from magnesium oxide derived from seawater by reacting it with water. Corn starch is subsequently incorporated during the wet granulation process to improve the handling and flow characteristics of the product. The Applicant has further stated that the corn starch functions as a binder during granulation and as an anti-caking agent in the finished product. It has also been submitted that trace minerals naturally present in the seawater-derived raw material remain in the finished product in residual quantities and are neither intentionally added nor deliberately retained to impart any particular characteristic to the product. On this basis, the Applicant has claimed classification of the subject goods under Tariff Item 28161010.

7.3 I find that the classification of imported goods is governed by the General Rules for the Interpretation of the Import Tariff (GIR), as provided in the First. Schedule to the Customs Tari Act, 1975. The relevant provision is reproduced below:

“Classification of goods in this Schedule shall be governed by the following principles:

1. The titles of Sections, Chapters and sub-Chapters are provided for ease of reference only; for legal purposes, classification shall be determined according to the terms of the headings and any relative Section or Chapter Notes and, provided such headings or Notes do not otherwise require, according to the following provisions.”

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GIR 1 requires classification to be determined primarily with reference to the terms of the relevant tariff headings and the applicable Section and Chapter Notes. Accordingly, the classification of Aquamin Mg TO is required to be examined with reference to Heading 2816 and Chapter Note 1 to Chapter 28, having regard to the composition, manufacturing process and functions of the constituents of the product in the form in which it is proposed to be imported.

7.4 Chapter 28 of the First Schedule to the Customs Tariff Act, 1975 covers inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements of Isotopes. However, the presence of an inorganic chemical compound in a product does not conclusively establish its classification under this Chapter. The product must satisfy the conditions prescribed under the relevant Chapter Notes. The relevant portion of Chapter Note 1 to Chapter 28 is reproduced below:

“1. Except where the context otherwise requires, the headings of this Chapter apply only to.

a. separate chemical elements and separate chemically defined compounds, whether or not containing impurities;

b. the products mentioned in (a) above dissolved in water;

c. the products mentioned in (a) or (b) above dissolved in other solvents provided that the solution constitutes a normal and necessary method of putting up these products adopted solely for reasons of safety or for transport and that the solvent does not render the product particularly suitable _.for specific use rather than for general use;

d. the products mentioned in (a), (b) or (c) above with au added stabiliser (including an anti-caking agent) necessary for their preservation or transport;

e. the products mentioned in (a), (b), (c) or (d) above with an added anti-dusting agent or a colouring substance added to facilitate their identification or for safety reasons, provided that the additions do not render the product particularly suitable for specific use rather than for general use.”

The above provision indicates that Chapter 28 covers separate chemically defined compounds, whether or not containing impurities, and permits certain specified additions subject to the conditions laid down therein. Consequently, where a product contains a chemically defined compound along with other constituents, it is necessary to examine the nature, purpose and function of those constituents to determine whether the product remains eligible for classification under Chapter 28.

7.5 I further find it necessary to consider the IISN Explanatory Notes to Chapter 28 which clarify the meaning of separate chemically defined compounds, the treatment of impurities and the conditions governing the addition of stabilisers and other substances. The relevant portions are reproduced below:

GENERAL

Unless the context otherwise requires, Chapter 28 is limited to separate chemical elements and separate chemically defined compounds.

A separate chemically defined compound is a substance which consists of one molecular species (e.g., covalent or ionic) whose composition is defined by a constant ratio of elements and can be represented by a definitive structural diagram. In a crystal lattice, the molecular species corresponds to the repeating unit cell.

The elements of a separate chemically defined compound combine in a specific characteristic proportion determined by the valency and the bonding requirements of the individual atoms. The proportion of each element is constant and specific to each compound and it is therefore said to be stoichiometric.

Small deviations in the stoichiometric ratios can occur because of gaps or insertions in the crystal lattice. These compounds are described as quasi-stoichiometric and are permitted as separate chemically defined compounds provided that the deviations have not been intentionally created.

(A) Chemically defined elements and compounds.
(Note 1)

Separate chemical elements and separate chemically defined compounds containing impurities, or dissolved in water, remain classified in Chapter 28.

The term “impurities” applies exclusively to substances whose presence in the single chemical compound results solely and directly from the manufacturing process (including purification). The substances may result from any of the factors involved in the process and are principally the following:

a. Unconverted starting materials.

b. Impurities present in the starting materials.

c. Reagents used in the manufacturing process (including purification).

d. By-products.

It should be noted, however, that such substances are not in all cases regarded as “impurities” permitted under Note 1 (a). When such substances are deliberately lefi in the product with a view to rendering it particularly suitable for specific use rather than for general use, they are not regarded as permissible impurities. 

Such elements and compounds are excluded from Chapter 28 when they are dissolved in solvents other than water, unless the solution constitutes a normal and necessary method ofputting up these products adopted solely_. for reasons ofsafety or for transport (in which case the solvent must not render the product particularly suitable for some types of use rather than for general use).

Thus, carbon chloride oxides dissolved in benzene; alcoholic solutions of ammonia and colloidal solutions of aluminium hydroxide are excluded from this Chapter and fall to be classified in heading 38.24. Generally speaking, colloidal dispersions fall in heading 38.24, unless covered by a more specific heading.

Separate chemically defined elements and compounds as described above, put up with an added stabiliser necessary for their preservation or transport, remain classified in this Chapter For example, hydrogen peroxide stabilised by addition of boric acid remains classified in heading 28.47; but sodium peroxide mixed with catalysts (for production of

hydrogen peroxide) is excluded from Chapter 28 and is classified in heading 3& 24. •

Products added to certain chemicals to keep them in their original physical state are also to he regarded as stabilisers, provided that the quantity added in no case exceeds that necessary to achieve the desired result and that the addition does not alter the character of the basic product and render it particularly suitable for specific use rather than for general use. By application of these provisions anti-caking agents may be added to the products of this Chapter. Such products with added water-repellents are, on the other hand, excluded since such agents modify the original characteristics of the products.

On the same condition that the additions do not render them particularly suitable_.for specific use rather than for general use, the products of Chapter may also contain:

a. Added anti-dusting agents (e.g., mineral oil added to certain poisonous chemicals to prevent dusting during handling).

b. Colouring substances added to facilitate identification or added for safety reasons to dangerous or poisonous chemicals (e.g.. lead arsenate of heading 28.42) as a “marker” or warning to those handling the products. Products to which colouring substances have been added for other reasons (e.g., silica gel with cobalt salts added for use as a humidity indicator (heading 38.24)) are, however excluded

The above Explanatory Notes clarify that impurities may be present in a separate chemically defined compound without necessarily excluding it from Chapter 28, provided that they arise solely and directly from the manufacturing process and are not deliberately retained to impart suitability for a particular use. They also clarify that an added stabiliser or anti-caking agent is permissible only when the prescribed conditions are satisfied, including that its quantity does not exceed what is necessary, the character of the basic product remains unaltered and the addition does not render the product particularly suitable for a specific use rather than for general use.

7.6 I find that the Applicant is relied upon the Supplier’s statement regarding composition to the subject product. The relevant portion is reproduced below:

“Hereby confirm that Marine Magnesium extracted fr-om Seawater naturally contains Trace Minerals from the sea. These trace minerals are part of the natural composition and cannot be segregated or removed livm Aquamin Mg TG, MgAG or Aquamin Mg Souble.

Corn Starch is required in Aquamn MgTG as a binder during the wet granulation process and as an anti-caking agent in the ,final product to help maintain the flow characteristics of^. the material.”

Applicability of Chapter Note 1(a): Separate chemical defined compound and impurities
7.7 I find that Chapter Note 1(a) to Chapter 28 covers separate chemically defined compounds, whether or not containing impurities. As explained in the FISN Explanatory Notes to Chapter 28, a separate chemically defined compound is a substance consisting of one molecular species having a composition defined by a constant ratio of elements and capable of being represented by a definitive structural diagram.

In the present case, the principal constituent of “Aquamin Mg TG” is marine magnesium hydroxide, constituting 95% or more of the product. Magnesium hydroxide, represented by the chemical formula Mg(OH)2, is a separate chemically defined inorganic compound. The Applicant has submitted that the product is manufactured by reacting magnesium oxide derived from seawater with water. The trace minerals naturally present in the seawater-derived starting material remain in the finished product as residual constituents and arc neither intentionally added nor deliberately retained to impart suitability for any specific use.

7.7 The HSN Explanatory Notes further clarify that impurities arising solely and directly from the manufacturing process, including impurities present in the starting materials and by­products, do not necessarily exclude a product from Chapter 28. In the present case, the Applicant has explained that the trace minerals originate naturally from the seawater-derived starting material. The Supplier has also confirmed that these trace minerals form part of the natural composition of the marine magnesium and cannot be segregated or removed from the product. In view of these submissions, the presence of such naturally occurring trace minerals does not preclude the application of Chapter Note 1(a), subject to their satisfying the conditions applicable to permissible impurities under the said Note and the relevant I ISN Explanatory Notes.

7.8 Accordingly, I find that the principal constituent of ^–Aquamin Mg TG” satisfies the requirement of a separate chemically defined compound under Chapter Note 1(a). The effect of the addition of corn starch is, therefore, required to be examined separately under Chapter Note 1(d).

Applicability of Chapter Note 1(d): Addition of Anti-Caking Agent
7.9 I find that Chapter Note 1(d) to Chapter 28 permits the products covered under Chapter Note 1(a), (b) or (c) to contain an added stabiliser, including an anti-caking agent, necessary for their preservation or transport. The relevant HSN Explanatory Notes further clarify that anti- caking agents may be added to the products of Chapter 28, provided that such addition does not alter the character of the basic product or render it particularly suitable for a specific use rather than for general use.

7.10 In the present case, the Applicant has submitted that corn starch is incorporated during the manufacturing process to improve the handling and flow characteristics of “Aquamin Mg TU^.‘ and functions as an anti-caking agent in the finished product. The Supplier has also confirmed that corn starch is used as a binder during the wet granulation process and as an anti-caking agent to help maintain the flow characteristics of the material. Thus, the submissions of both the Applicant and the Supplier identify the function of corn starch as being related to the physical handling and flow characteristics of the product.

7.11 I find that the addition of corn starch as an anti-caking agent is required to be examined in the light of Chapter Note 1(d) and the corresponding HSN Explanatory Notes. Where the addition serves the purpose of maintaining the physical condition of the product during handling or transport, without altering the character of the basic chemically defined compound or rendering it particularly suitable for a specific use rather than for general use, such addition does not exclude the product from Chapter 28.

7.12 Accordingly, the addition of corn starch as an anti-caking agent does not constitute a ground for excluding “Aquamin Mg TG” from Chapter 28, provided the conditions prescribed under Chapter Note 1(d) are satisfied. The classification of the subject goods is, therefore, required to be determined with reference to the relevant tariff heading and subheading, read with GIR 1 and the applicable Chapter Notes.

Determination of tariff classification

7.13 Having examined the subject goods with reference to Chapter Note 1(a), in respect of the separate chemically defined compound and the naturally occurring trace minerals, and Chapter Note 1(d), in respect of the addition of corn starch as an anti-caking agent, I find that the product, as described in the application and supported by the material placed on record, satisfies the relevant conditions for classification under Chapter 28. The relevant tariff heading and subheading are reproduced below:

I find that Heading 2816 specifically covers hydroxide of magnesium. Since magnesium hydroxide is the principal constituent of “Aquamin Mg TG” and the presence of naturally occurring trace minerals and the addition of corn starch, as examined above, do not, subject to the applicable conditions, preclude its classification under Chapter 28, the product merits classification under Tariff Item 28161010 of the First Schedule to the Customs Tariff Act, 1975, in accordance with GIR 1.

7.14 In view of the foregoing discussion and findings, I conclude that Aquamin Mg TG, as described in the application, is classifiable under Tariff Item 28161010 (Hydroxide of magnesium), subject to the product as imported conforming to the composition, manufacturing process and functions of the constituents described and evidenced in the present proceedings.

8. I rule accordingly.