29332900
ORGANIC CHEMICALS›Heterocyclic compounds with nitrogen hetero-atom(s) only
Other
Subcodes (2)
Scope and main substances of subheading 293329
CN subheading 293329 covers other heterocyclic compounds containing an unfused imidazole ring, not classified in more specific subheadings 293321 to 293328. The imidazole ring (1,3-diazole) is a five-membered aromatic system with two nitrogen atoms characterised by amphoteric properties - the ability to act as both an acid and a base. Key substances classified here include: imidazole (CAS 288-32-4) - a pharmaceutical building block and catalyst in organic synthesis; histamine (CAS 51-45-6) - an endogenous biogenic amine that mediates allergic responses, gastric acid secretion and inflammatory processes; clotrimazole (CAS 23593-75-1) - a synthetic imidazole antifungal agent used to treat skin and mucosal infections; as well as bifonazole, fenticonazole and other azole active substances. Imidazole is an important structural unit in drug discovery, agrochemicals, surfactants and polymers. Histamine is produced by bacterial decarboxylation of histidine in food and serves as a spoilage indicator in fishery products. Clotrimazole is the active ingredient in widely used over-the-counter dermatological and gynaecological preparations. Classification under subheading 293329 requires the imidazole ring to be present in an unfused form as the essential structural feature. Mixtures of several imidazole substances are not classified under Chapter 29.
REACH and CLP obligations for imidazole compounds imported into the EU
Substances classified under subheading 293329 are subject to REACH Regulation (EC) No 1907/2006. Imidazole imported above one tonne per year must be registered with ECHA; an active registration exists within the relevant Substance Information Exchange Forum (SIEF). Under CLP Regulation (EC) No 1272/2008, imidazole is classified as toxic for reproduction category 1B (H360D) - may damage the unborn child - harmful if swallowed (H302) and as a flammable solid (H228). It has been added to the SVHC Candidate List by ECHA on grounds of reproductive toxicity and may in future require authorisation under REACH Annex XIV, which importers should monitor proactively. Clotrimazole, as a pharmaceutical active substance, may only be imported by entities holding appropriate pharmaceutical manufacturing or wholesale distribution authorisations under Directive 2001/83/EC and Regulation (EC) No 726/2004. Histamine for diagnostic or research use is subject to standard REACH registration and requires appropriate toxicological documentation. Safety Data Sheets for all substances must be prepared in accordance with Annex II of Regulation (EU) 2020/878 and delivered to professional recipients before first supply.
Customs documentation and import requirements for CN 293329
Importing goods under subheading 293329 requires a correct customs declaration with the 8-digit TARIC code. Documentation should include a commercial invoice stating the full chemical name (IUPAC or common name), CAS and EC numbers, a technical specification or certificate of analysis (CoA) with declared purity, a Safety Data Sheet (SDS) in the language of the importing country, a transport document and a packing list. Imidazole is flammable and irritating, requiring classification as dangerous goods under ADR Class 4.1 or 6.1 depending on the physical form and physicochemical parameters. Clotrimazole and other active substances with pharmacological activity may be subject to additional border inspection by the pharmaceutical inspectorate or food safety authority. Current MFN tariff rates, any anti-dumping measures and preferential rates under EU free trade agreements must be verified in the TARIC database before lodging the customs declaration. For preferential tariff rates, an EUR.1 movement certificate or supplier declaration on the invoice is required. The SVHC status of imidazole requires importers of articles containing it above 0.1% to communicate safe use information to recipients on request, and REACH registration documentation must be retained throughout the period of import activity.
Chemical safety and SDS requirements
Organic substances under CN code 2933 29 (Other compounds with unfused imidazole ring) require detailed chemical documentation for customs clearance. The Safety Data Sheet must comply with REACH Annex II. Substances classified as hazardous under CLP require GHS pictogram labelling. Transport follows ADR (road) or IMDG (maritime) regulations. Some organic substances may be subject to export controls as dual-use goods. Importers should verify whether the substance requires REACH authorisation (Annex XIV) or is subject to restrictions (Annex XVII).
Frequently asked questions
Is imidazole an SVHC substance and what obligations does this create?
Yes. Imidazole (CAS 288-32-4) has been added to the ECHA SVHC Candidate List as a reproductive toxicant category 1B (H360D). Importers of articles containing imidazole above 0.1% must provide safe use information to recipients or consumers upon request. Manufacturers and importers of substances or mixtures containing imidazole must comply with REACH registration requirements above one tonne per year and provide an SDS with extended exposure scenarios. Additionally, importers should monitor ECHA updates as imidazole may in future be included in REACH Annex XIV, which would trigger a mandatory authorisation obligation before the substance could continue to be placed on the EU market.
What requirements apply when importing clotrimazole as a pharmaceutical substance?
Clotrimazole (CAS 23593-75-1) imported as an active pharmaceutical ingredient is subject to both REACH and EU pharmaceutical legislation. The importer must hold a Good Manufacturing Practice (GMP) certificate or engage an entity holding one. The active substance may only be imported by registered pharmaceutical importers in accordance with Directive 2001/83/EC and Delegated Regulation (EU) 2017/1569. Quality documentation - a certificate of analysis compliant with European Pharmacopoeia specifications - is required at each import shipment. Customs authorities may verify GMP documentation during border checks, and any discrepancy between the declared use and the regulatory status of the substance may result in the consignment being held for further inspection.
Why is histamine classified under CN 293329 relevant to fishery product trade?
Histamine (CAS 51-45-6) is a biogenic amine formed through bacterial decarboxylation of histidine in fish tissues stored under inadequate temperature conditions. Regulation (EC) No 2073/2005 on microbiological criteria sets maximum permitted histamine levels in fishery products - generally 100 to 200 mg/kg depending on species and processing method. Importation of histamine as a pure chemical substance for diagnostic use or as a calibration standard follows a separate customs procedure under CN 293329, distinct from fishery product controls under food safety legislation. Importers of the pure substance must nonetheless clearly declare the intended use in the customs declaration to avoid confusion with food safety enforcement checks.
How to classify Other compounds with unfused imidazole ring in customs tariff 2933 29?
Classification of Other compounds with unfused imidazole ring under CN code 2933 29 is based on chemical structure and functional groups. If in doubt, you can apply for Binding Tariff Information (BTI) from the national customs authority.
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