HS code · 6-digit subheading
HS Code 3913.90 – Polymers, natural and modified natural; in primary forms (excluding alginic acid, its salts and esters)
HS code 3913.90 is the 6-digit subheading for polymers, natural and modified natural, in primary forms (excluding alginic acid, its salts and esters). It is used for chitosan, dextran, gellan gum, xanthan gum and guar gum (modified).
What HS 3913.90 covers
This HS code encompasses a broad array of natural and modified natural polymers in primary forms, excluding alginates. This category includes substances like chitosan, dextran, natural rubber (if not covered by specific rubber codes), and various other polysaccharides and biopolymers. These materials are traded globally for their diverse applications in pharmaceuticals, cosmetics, food, textiles, and industrial uses. Major importers are countries with advanced manufacturing and research sectors, such as the USA, Japan, and Germany, seeking specialized functional ingredients. Exporters often come from regions rich in natural resources or with strong biotechnology industries. The trade involves a wide range of products, each with unique properties and applications, requiring careful specification and quality control. The increasing focus on sustainable and bio-based materials is a significant driver for this segment of the polymer market.
- Covers
- Chitosan
- Dextran
- Gellan gum
- Xanthan gum
- Guar gum (modified)
- Gum arabic (modified)
- Pectin (modified)
- Examples
- Kitozyme Chitosan
- Pharmacosmos Dextran
- CP Kelco Gellan Gum
- Cargill Xanthan Gum
- Ingredion Modified Starch
Codes often confused with 3913.90
Common mistake. This is a broad "other" category for natural polymers and can be easily confused with 391310 (alginates) or even specific cellulose derivatives under 3912 if the natural origin and specific chemical structure are not clearly defined.
Top exporters and importers of HS code 391390, 2025
In 2025, the largest exporter of HS code 391390 in UN Comtrade data was Sweden, with 32% of world exports; the largest importer in UN Comtrade data was South Korea, with 12% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Top exporters 2025 · share of world exports
- 1 Sweden $1.1B 32% of world exports
- 2 China $803M 23% of world exports
- 3 United States $344M 9.8% of world exports
World total: $3.5B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 South Korea $412M 12% of world imports
- 2 United States $388M 11% of world imports
- 3 Japan $240M 6.7% of world imports
World total: $3.6B Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM codes for 3913.90 9
Brazil splits HS 3913.90 into 9 NCM codes, Mercosur's 8-digit tariff lines.
- 3913.90.1 Chemical derivatives of natural rubberDerivados químicos da borracha natural Group
- 3913.90.11 Chlorinated/hydrochlorinated rubber, bulk formsBorracha clorada ou cloridratada, nas formas previstas na Nota 6 b) deste Capítulo
- 3913.90.12 Chlorinated rubber in other formsBorracha clorada, noutras formas
- 3913.90.19 Other chemical derivatives of natural rubberOutros
- 3913.90.20 Xanthan gumGoma xantana
- 3913.90.30 DextranDextrana
- 3913.90.40 Hardened proteinsProteínas endurecidas
- 3913.90.50 Chitosan, its salts or derivativesQuitosana, seus sais ou seus derivados
- 3913.90.60 Chondroitin sulphateSulfato de condroitina
- 3913.90.90 Other natural or modified natural polymersOutros
All Brazil NCM codes in heading 39.13 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 3913.90
What is HS code 391390?
HS code 391390 is a 6-digit subheading in the Harmonized System that covers: Polymers, natural and modified natural; in primary forms (excluding alginic acid, its salts and esters). This HS code encompasses a broad array of natural and modified natural polymers in primary forms, excluding alginates. This category includes substances like chitosan, dextran, natural rubber (if not covered by specific rubber codes), and various other polysaccharides and biopolymers. These materials are traded globally for their diverse applications in pharmaceuticals, cosmetics, food, textiles, and industrial uses. Major importers are countries with advanced manufacturing and research sectors, such as the USA, Japan, and Germany, seeking specialized functional ingredients. Exporters often come from regions rich in natural resources or with strong biotechnology industries. The trade involves a wide range of products, each with unique properties and applications, requiring careful specification and quality control. The increasing focus on sustainable and bio-based materials is a significant driver for this segment of the polymer market.
What products fall under HS code 391390?
Chitosan, Dextran, Gellan gum, Xanthan gum, Guar gum (modified), Gum arabic (modified), Pectin (modified)
What are common misclassifications for HS code 391390?
This is a broad "other" category for natural polymers and can be easily confused with 391310 (alginates) or even specific cellulose derivatives under 3912 if the natural origin and specific chemical structure are not clearly defined.
Which countries are the top exporters of goods under HS code 391390?
In 2025, the top exporters of HS code 391390 in UN Comtrade data were Sweden ($1.1B, 32% of world exports), China ($803M) and the United States ($344M). World exports came to about $3.5B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of goods under HS code 391390?
In 2025, the top importers of HS code 391390 in UN Comtrade data were South Korea ($412M, 12% of world imports), the United States ($388M) and Japan ($240M). World imports came to about $3.6B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
How is HS code 391390 structured?
HS code 391390 is a 6-digit subheading under the Harmonized System. The first 2 digits (39) identify the chapter, digits 3-4 (13) identify the heading, and digits 5-6 (90) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 391390?
Brazil splits HS code 391390 into 9 NCM codes: 3913.90.11 (Chlorinated/hydrochlorinated rubber, bulk forms), 3913.90.12 (Chlorinated rubber in other forms), 3913.90.19 (Other chemical derivatives of natural rubber), 3913.90.20 (Xanthan gum), 3913.90.30 (Dextran), 3913.90.40 (Hardened proteins), 3913.90.50 (Chitosan, its salts or derivatives), 3913.90.60 (Chondroitin sulphate), and more listed on this page. The first 6 digits of each match the HS code.