Compliance for monoethanolamine (MEA) in the European market is defined by the MEA REACH & CLP Compliance: Classification, SDS and Labelling Checklist. The substance is identified as 2-aminoethanol, CAS 141-43-5, EC 205-483-3 and Annex VI index number 603-030-00-8. It is registered under Regulation (EC) No 1907/2006 as a full joint submission with a registered tonnage band of 100 000–1 000 000 tonnes per annum; since the substance is classified as hazardous and is not an isolated intermediate, the registration dossier includes a chemical safety report and exposure scenarios. The SDS format in force is REACH Annex II as amended by Commission Regulation (EU) 2020/878, applicable from 1 January 2021. For MEA, the decisive compliance issues are not physical property data but the two Annex VI concentration boundaries at 5% and 1%, which alter mixture-level classification, packaging duties and the content of the extended SDS.

Does the Harmonised Annex VI Entry for MEA Differ from the C&L Inventory Self-Classifications?

Under CLP Annex VI Part 3 Table 3.1, the harmonised classification for MEA is Acute Tox. 4 H302, Acute Tox. 4 H312, Acute Tox. 4 H332, Skin Corr. 1B H314, Eye Dam. 1 H318 and STOT SE 3 H335. This set activates two hazard pictograms: GHS05 from the skin corrosion/eye damage classes and GHS07 from the acute toxicity and specific target organ toxicity single exposure classes. The assigned signal word is Danger. Annex VI includes specific concentration limits that override the generic concentration thresholds: at ≥5% MEA, the mixture must be classified Skin Corr. 1B H314; at 1% to <5%, the mixture must be classified Eye Irrit. 2 H319. This is a critical threshold set because many mild alkaline formulations sit in the 3%–5% window. The CLP C&L inventory additionally contains self-classifications, frequently Aquatic Chronic 3 H412, but that environmental classification is not harmonised and therefore cannot be transferred automatically to a mixture without either the mixture supplier’s own assessment or a decision to adopt the notifier classification under CLP Article 9. For a compliant SDS, Section 2 must state the harmonised classification and the SCLs; failure to reproduce the 1% Eye Irrit. 2 boundary is a recurring audit deficiency.

The acute toxicity endpoints behind the harmonised classification are supported by REACH registration data. Published registration summaries for ethanolamine report an oral LD50 in the rat near 1 720 mg/kg bw, a dermal LD50 in the rabbit near 1 000 mg/kg bw and an inhalation LC50 consistent with harmful classification. The corrosive action is not a dilute-solution artefact; aqueous MEA is strongly alkaline, and short-contact skin damage drives the Skin Corr. 1B assignment. For SDS Section 11, the most operationally relevant statements are route-specific: ingestion may produce oral burns, skin contact requires immediate washing, and inhalation of mists or vapours must be terminated by moving the exposed person to fresh air. Section 2.3 must also confirm that current registration data do not identify MEA as an endocrine disruptor; REACH Annex II as amended by 2020/878 requires this content to be addressed even when the outcome is negative.

CLP label elements are not generated by direct copying of Annex VI alone. The supplier must select the precautionary statement set from Annex IV based on the exposure routes and use conditions. The minimum practical P-statement set for a pure MEA label is P260, P264, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P363, P405 and P501. P312 is added where the supplier chooses to include route-specific medical advice; it is not optional in the SDS hazard communication logic where Acute Tox. 4 routes are present. The label must be written in the official language or languages of the Member State of placement under CLP Article 17(2), and the SDS must be supplied free of charge under REACH Article 31(8).

SDS Section 3 Composition, DNEL Metrics and Transport Benchmarks

A MEA SDS is judged not only by hazard statements but also by the completeness of Sections 3, 8, 9 and 14. Section 3 must identify the product as 2-aminoethanol with CAS 141-43-5, EC 205-483-3 and index 603-030-00-8; typical commercial specification is ≥99.0% by mass MEA. No M-factor is assigned in the harmonised entry. Section 8 must carry the worker DNELs from the lead registrant’s chemical safety report. Registered representative values are a long-term inhalation DNEL of 3.3 mg/m³ as an 8-hour time-weighted average and a dermal long-term DNEL of 0.24 mg/kg bw/day. An SDS that lists only national OELs without these DNELs does not support REACH exposure-scenario verification. Section 9 should contain the transport-relevant physical property set: boiling point 170.5 °C at 101.3 kPa, closed-cup flash point 93 °C by ASTM D93, density 1.016 g/cm³ at 20 °C by ASTM D4052, and vapour pressure 0.4 hPa at 20 °C. Section 14 must classify the pure material as UN 2491, ethanolamine, Class 8, Packing Group III, a corrosive liquid according to ADR/RID. Section 15 must state that MEA is not listed in REACH Annex XIV and is not subject to a specific Annex XVII restriction entry; it must also reference the harmonised Annex VI entry. Table 1 provides the SDS verification matrix.

When 5% MEA Becomes the Decision Boundary for Consumer Packaging

The 5% SCL is not merely a label issue; it is a packaging and notification switch. A formulated hard-surface cleaner containing 4.8% MEA may fall below the corrosive threshold but above the 1% threshold, producing Eye Irrit. 2 H319 and no child-resistant fastening obligation. The same batch adjusted to 5.2% MEA becomes Skin Corr. 1B H314, triggering the GHS05 pictogram, the Danger signal word and the packaging duties of CLP Article 35(2) when the product is supplied to the general public. Child-resistant fastening must be verified to ISO 8317; the tactile warning of danger must comply with EN ISO 11683. In gas-treating operations, aqueous MEA is typically handled at amine strengths of 15%–30% by mass, so the circulating solution and any shipped premix are already deeply above the corrosive SCL. The transport classification of such a mixture, however, is determined by the full formulation and not by the MEA SCL alone; a mixture that is not Class 8 under ADR cannot be labelled as corrosive for transport simply because the CLP SCL is exceeded. This separation between CLP labels and transport labels must be maintained in Sections 2 and 14.

For mixtures containing MEA that are classified on the basis of health or physical hazards, the poison-centre notification obligation under CLP Article 45 and Annex VIII applies. The UFI must be placed on the mixture label; pure MEA as a registered substance is outside the Annex VIII mixture notification format. Downstream formulators selling MEA-containing cleaners or water-treatment products must generate the UFI and submit the formulation file through the ECHA submission portal. The UFI is a 16-character alphanumeric code and cannot be replaced by the CAS number of MEA on a mixture label.

MEA is hygroscopic and readily absorbs carbon dioxide, forming amine carbamate and carbonate species that increase viscosity and modify pH; closed storage under a nitrogen blanket is required where product colour and water content must remain within specification. The substance is corrosive to copper, zinc, aluminium and galvanised steel under moist conditions; carbon steel may be acceptable for anhydrous product but Type 316L stainless steel is preferred for long-term storage and piping. These incompatibilities must appear in SDS Sections 7.2 and 10.4, not as optional guidance. In external audits, a common failure is the absence of specific metal incompatibility data in Section 10.4 or the omission of carbon dioxide absorption as a condition to avoid in Section 10.3. The SDS must also state in Section 6.1 that spills should be contained and neutralised only after a written procedure; direct water jet application to a large MEA spill can generate an alkaline aerosol and should be avoided. The exposure scenarios attached to the SDS for gas sweetening and water treatment should include maintenance operations such as filter change-out, pump seal replacement and vessel entry, because these tasks generate dermal and inhalation exposure patterns that differ from continuous closed-loop operation.

REACH compliance for MEA extends beyond the label and the 16-section SDS. A downstream user receiving MEA with exposure scenarios must verify that its use is covered. If the use is not covered, the downstream user must either arrange coverage through the supplier under REACH Article 37(2) or prepare a downstream user chemical safety report under Article 37(4) where the use is not exempt. SDS version control must be traceable; under REACH Article 31(9), suppliers must update without delay when new hazard information, changed classification, authorisation or restriction data, or formulation composition changes affect the required content. Section 16 should identify the previous revision date and the nature of the changes in a reversible audit trail. The MEA REACH & CLP Compliance: Classification, SDS and Labelling Checklist therefore functions as an incoming-material audit and an outgoing-document audit: the substance identifiers, harmonised classification set, 5% and 1% SCLs, DNEL figures, transport classification, UFI logic and Article 35 packaging duties all appear in the verification record.