DMSO HS Code, ICH Limits & Import/Export Guide for B2B Buyers
Customs classification, residual-solvent limits, documentation, and a multilingual buyer FAQ for international DMSO trade.
Importing dimethyl sulfoxide (DMSO, CAS 67-68-5) is, on paper, one of the more straightforward chemical procurements. DMSO classifies under HS heading 2930.90 (organo-sulfur compounds), is not regulated as Dangerous Goods for international transport, and sits in ICH Q3C Class 3 for pharmaceutical residual-solvent purposes - all of which simplify clearance and lower freight cost compared to flammable or DG-classified solvents.
But "straightforward" still requires the correct paperwork: the right HS / HSN code for your country, a batch COA, the SDS, a certificate of origin, packing list, and confirmation of the chemical-inventory listing for your destination. This guide walks through the customs classification, the ICH limits buyers ask about, the full documentation checklist, and a multilingual buyer FAQ. For market context, pair it with our global DMSO market 2026 article.
01. HS Code for DMSO 📦
DMSO is classified under the World Customs Organization Harmonized System at the 6-digit level as:
Heading 2930 covers organo-sulfur compounds; subheading 2930.90 is the "other" basket for organo-sulfur compounds not given their own specific subheading. DMSO - a sulfoxide with sulfur directly bonded to carbon - falls squarely here, as confirmed by customs rulings (e.g., US CBP ruling NY N091622 classifying bulk DMSO under HTSUS 2930.90.9190).
02. HSN Code & Country Variations 🌐
"HSN code" (Harmonized System of Nomenclature) is the term used in India and several other countries for the same classification system. The full national codes for DMSO in major markets:
| Country / Region | Full Code for DMSO |
|---|---|
| WCO (international 6-digit) | 2930.90 |
| India (HSN, 8-digit) | 2930.90.99 (29309099) - most commonly used |
| USA (HTSUS, 10-digit) | 2930.90.9190 (per CBP ruling) |
| EU (CN, 8-digit) | 2930.90.98 (subject to current CN refinements) |
| GCC (12-digit, from 2025) | Extended from 2930.90 - confirm current GCC tariff |
Important: these codes are indicative and subject to periodic revision (the HS nomenclature is updated by the WCO roughly every five years, and national tariffs change more often). Always verify the current code with your customs broker or the destination country's tariff portal before shipment.
03. ICH Q3C Residual-Solvent Limit 💊
Buyers in the pharmaceutical supply chain frequently ask about the "DMSO ICH limit." Here is the precise answer:
DMSO is an ICH Q3C Class 3 residual solvent - the lowest-risk category. Class 3 solvents are regarded as having low toxic potential to humans; no health-based exposure limit is needed, and residual DMSO up to 0.5 % (5,000 ppm) in a finished drug product is generally acceptable without further toxicological justification. This is far more permissive than the Class 2 amide solvents (DMF, NMP, DMAc), which require strict PDE-based limits.
For the full pharmaceutical-sourcing picture - USP / EP / JP monographs, COA requirements, packaging compatibility - see our pharmaceutical DMSO sourcing guide and DMSO grades explained article.
04. Customs Documentation Checklist 📋
A typical DMSO import shipment should arrive with the following documents. Missing paperwork is the most common cause of customs delays:
- ✅ Commercial Invoice - value, Incoterms, HS code, buyer/seller details
- ✅ Packing List - number and type of containers (drums / IBCs / ISO tank), net & gross weight
- ✅ Certificate of Analysis (COA) - batch-specific, with GC purity, water, color, and grade-relevant tests
- ✅ Safety Data Sheet (SDS) - 16-section GHS-compliant (see our DMSO SDS article)
- ✅ Certificate of Origin (COO) - for preferential duty under trade agreements where applicable
- ✅ Bill of Lading / Air Waybill - transport document
- ✅ Non-DG declaration - confirming DMSO is not classified as Dangerous Goods
- ✅ Import license / registration - where the destination country requires it for chemicals
- ✅ For pharma grade: additional GMP statement, residual-solvent panel, and any required drug-master-file reference
05. Transport Classification (Non-DG) 🚚
One of DMSO's biggest logistical advantages: it is not regulated as Dangerous Goods by any major transport authority. Its flash point (87–95 °C) is above the 60 °C threshold for UN Class 3 flammable liquids, and its toxicity is below the Class 6.1 threshold.
- UN number: none assigned (not a listed dangerous good)
- IATA / ICAO (air): not regulated
- IMDG (sea): not regulated
- ADR (EU road) / US DOT: not regulated
This means DMSO ships as ordinary cargo in standard packaging - 250 kg drums, 1100 kg IBCs, or ISO tanks - without the surcharges, restricted-route requirements, or specialized documentation that DG-classified solvents incur. For storage and handling once it arrives, see our DMSO storage & handling guide.
06. Chemical-Inventory Listings by Country 🗂️
Before importing DMSO into a regulated market, confirm it is listed on (or compliant with) the destination country's chemical inventory. DMSO is a well-established commodity and is listed on all major inventories:
| Region | Inventory / Requirement |
|---|---|
| EU / UK | REACH registered (EC 200-664-3); UK REACH for GB imports |
| USA | TSCA inventory listed |
| Canada | DSL (Domestic Substances List) |
| China | IECSC listed |
| Australia | AICS listed |
| Japan / Korea | ENCS (JP) / KECI (KR) listed |
A reputable supplier states inventory listings in Section 15 of the SDS. Always verify the listing relevant to your import country before placing a bulk order.
07. Multilingual Buyer FAQ 🌐
DMSO is traded globally, and buyers search for it in many languages. Quick answers to the most common multilingual queries (all referring to the same compound, CAS 67-68-5):
El dimetil sulfóxido (DMSO) es un disolvente aprótico polar de baja toxicidad, usado como disolvente industrial, portador farmacéutico, crioprotector celular y potenciador de penetración cutánea. (DMSO is a low-toxicity polar aprotic solvent used as an industrial solvent, pharmaceutical carrier, cell cryoprotectant, and skin penetration enhancer.)
Dimetil sülfoksit (DMSO), endüstriyel çözücü, farmasötik taşıyıcı, hücre kriyoprezervasyonu ve cilt penetrasyon artırıcı olarak kullanılan düşük toksisiteli polar aprotik bir çözücüdür. (DMSO is a low-toxicity polar aprotic solvent used as an industrial solvent, pharmaceutical carrier, for cell cryopreservation, and as a skin penetration enhancer.)
DMSO içeren onaylı ilaçlar arasında Pennsaid (topikal diklofenak, %45,5 DMSO), RIMSO-50 (intravezikal %50 DMSO) ve Onyx sıvı embolik sistemi bulunur. (Approved drugs containing DMSO include Pennsaid, RIMSO-50, and the Onyx liquid embolic system.)
Dimetylosulfotlenek (DMSO) to organiczny związek siarki, polarny rozpuszczalnik aprotonowy o niskiej toksyczności, mieszający się z wodą. (DMSO is an organosulfur compound, a low-toxicity, water-miscible polar aprotic solvent.)
"Dimetil sulfóxido" es el nombre en español del DMSO (CAS 67-68-5). También conocido como metilsulfinilmetano. ("Dimetil sulfóxido" is the Spanish name for DMSO, CAS 67-68-5, also called methylsulfinylmethane.)
08. Tips for First-Time Importers 🧭
- Confirm the full national HS code with your customs broker before shipment - the WCO 2930.90 is just the starting point.
- Verify inventory listing (REACH / TSCA / DSL / AICS etc.) for your country - DMSO is listed everywhere, but you must reference the right one.
- Insist on a manufacturer (not trader) relationship for traceability, especially for pharma / cosmetic grade. (See our note on this in the global DMSO market article.)
- Use the non-DG status to your advantage - DMSO ships as ordinary cargo, so you can consolidate it with other non-DG freight and avoid DG surcharges.
- Order a sample first to qualify the grade and supplier before committing to a full container.
- Plan for DMSO's freezing point (18.5 °C) - in winter shipping, the material may solidify in transit. It re-liquefies cleanly on gentle warming with no quality loss (covered in our storage & handling guide).
Frequently Asked Questions
DMSO classifies under HS heading 2930.90 (organo-sulfur compounds, other) at the international 6-digit WCO level. National codes extend this: India uses HSN 29309099, the USA uses HTSUS 2930.90.9190, the EU uses CN 2930.90.98. Always confirm the full national code with your customs broker, as it sets the duty rate.
The most commonly used HSN code for DMSO in India is 29309099 (organo-sulfur compounds - other). This 8-digit code determines the import duty, GST rate, and any duty-drawback eligibility. Verify with your Indian customs agent, as classification choice affects duty and export benefits.
DMSO is an ICH Q3C Class 3 residual solvent (low toxic potential), with a permitted daily exposure of ≥ 50 mg/day. Residual DMSO up to 0.5 % (5,000 ppm) in a finished drug is generally acceptable without further justification - much more permissive than Class 2 solvents like DMF or NMP.
No. DMSO is not classified as Dangerous Goods by IATA, IMDG, US DOT, or ADR. Its flash point (87–95 °C) is above the UN Class 3 flammable threshold and its toxicity is below the Class 6.1 threshold. It ships as ordinary cargo, which simplifies logistics and lowers freight cost.
Standard set: commercial invoice, packing list, batch COA, SDS, certificate of origin, bill of lading / air waybill, and a non-DG declaration. For pharmaceutical grade, add a GMP statement and residual-solvent panel. Confirm any import license and the chemical-inventory listing (REACH / TSCA / DSL etc.) required for your country.
📚 Authoritative References
- World Customs Organization - HS Nomenclature 2022 Edition
- ICH - Q3C(R8) Residual Solvents Guideline
- US CBP - Customs Rulings Online Search (CROSS) - DMSO classification
- ECHA - DMSO Substance Info Card (EC 200-664-3)
- PubChem - Dimethyl Sulfoxide (CID 679)
🔗 Continue Reading - DMSO Knowledge Hub
Export-Ready DMSO with Complete Documentation
Sinolook Chemical Co., Ltd. supplies dimethyl sulfoxide (CAS 67-68-5) export-ready with batch COA, SDS, certificate of origin, and non-DG declaration - correctly classified under HS 2930.90, shipped in drums, IBCs, and ISO tanks to 50+ countries.
