Loading...
HSChapter 39
U.S. imports of natural and modified natural polymers (nesoi), in primary forms (HS 391390) totaled $37.6M in April 2026, traded with 42 countries.
Importers of Natural and Modified Natural Polymers (NESOI), in Primary Forms paid $3.5M in duties in April 2026 — an effective duty rate of 10% on $34.0M in dutiable value, based on actual customs collections rather than the published tariff schedule. Natural and Modified Natural Polymers (NESOI), in Primary Forms imports of $37.6M in April 2026 ran 24% above the year-to-date monthly average of $30.2M.
Last updated: April 2026 dataA broad residual heading covering biopolymers and chemically modified natural polymers not classified elsewhere, including xanthan gum (3913902015), chemical derivatives of natural rubber (3913901000), and other polysaccharides and their derivatives (3913902090). Xanthan gum — a fermentation-derived thickener critical to food, oilfield drilling fluids, and personal care products — is among the most commercially significant lines, with China the leading supplier across most subheadings. Importers should note that food-grade xanthan gum and other edible polysaccharides are subject to FDA review, while industrial grades used in drilling or coatings face different compliance considerations. Classification disputes can arise at the boundary between this heading and Chapter 35 (modified starches) or Chapter 13 (natural gums), making precise product specification documentation essential.
AI-written summary of the official U.S. Census Bureau trade figures on this page — verify before relying on it.
Xanthan gum is specifically identified by its own 10-digit line (3913902015) and is classified there regardless of end use — food, oilfield, or cosmetic. Other microbial or plant-derived polysaccharides not specifically named fall under 3913902090. The key is confirming the chemical identity of the polymer; a technical data sheet or certificate of analysis identifying the substance as xanthan gum (produced by Xanthomonas campestris fermentation) supports the specific line.
Chapter 13 covers natural gums, resins, and vegetable saps in their unmodified state, while Chapter 39 applies once those substances have been chemically modified or processed into primary polymer forms. A certificate of analysis showing the degree of chemical modification (e.g., carboxymethylation, esterification) and a product specification sheet are the most effective documents for supporting a Chapter 39 classification and defending it during CBP review.
| Country | Imports | Exports | Balance |
|---|---|---|---|
| SWEDEN | $8.7M | $9K | -$8.7M |
| JAPAN | $553K | $7.2M | +$6.7M |
| CHINA | $5.8M | $1.6M | -$4.2M |
| AUSTRIA | $6.6M | $8K | -$6.6M |
| UNITED KINGDOM | $5.9M | $536K | -$5.4M |
Supplier Network
Get discovered by U.S. importers searching for HS 391390 — Natural and Modified Natural Polymers (NESOI), in Primary Forms. Be the first supplier listed.
Monthly import values over time
HS10 import codes under this HS6 parent. Source: U.S. Harmonized Tariff Schedule.
| Code | Description | Import Value | Effective Tariff % | Duty Collected |
|---|---|---|---|---|
| 3913902090 | POLYSACCHARIDES & THEIR DERIVATIVES, NESOI | $21.9M | 9.21% | $1.8M |
| 3913902015 | XANTHAN GUM | $10.1M | 12.75% | $1.3M |
| 3913905000 | NATURAL POLYMERS & MODIF NAT POLYMRS,PRIM FM,NESOI | $5.3M | 8.41% | $365K |
| 3913901000 | CHEMICAL DERIVATIVES OF NATURAL RUBBER | $337K | 10.05% | $23K |
POLYSACCHARIDES & THEIR DERIVATIVES, NESOI
XANTHAN GUM
NATURAL POLYMERS & MODIF NAT POLYMRS,PRIM FM,NESOI
CHEMICAL DERIVATIVES OF NATURAL RUBBER
HS10 export codes under this HS6 parent. Source: U.S. Schedule B export classification.
| Code | Description | Export Value |
|---|---|---|
| 3913908000 | NATURAL POLYMERS & MODIF NAT POLYMRS,PRIM FM,NESOI | $29.5M |
| 3913901000 | CHEMICAL DERIVATIVES OF NATURAL RUBBER | $1.5M |
NATURAL POLYMERS & MODIF NAT POLYMRS,PRIM FM,NESOI
3.0M kg
CHEMICAL DERIVATIVES OF NATURAL RUBBER
319.8K kg
ARTICLES OF PLASTICS, NESOI
HS 392690
FLOOR, WALL, ETC COVERS, VINYL CHLORIDE POLYMERS
HS 391810
TABLEWARE AND KITCHENWARE OF PLASTICS
HS 392410
SACKS & BAGS (INCL CONES) OF POLYMERS OF ETHYLENE
HS 392321
HOUSEHOLD AND TOILET ARTICLES NESOI OF PLASTICS
HS 392490
PLATES, SHEETS ETC, NON-CELL ETC, POLYMER
HS 392010
| Port | Imports | Exports | Balance |
|---|---|---|---|
| LOS ANGELES, CA | $2.6M | $8.6M | +$6.0M |
| NEWARK, NJ | $9.6M | $896K | -$8.7M |
| NORFOLK-NEWPORT NEWS, VA | $3.0M | $3.6M | +$643K |