Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

The substance analogue TMAH has been established to be corrosive, category 1B. In view of the high pH of TEAH aqueous solutions due to the hydroxide ion, a similar effect on skin is expected, thus TEAH, as well as the registered substance (TEAH 35% in water), are also considered to be corrosive to skin, category 1B.
Any eye irritation study is waived as the registered substance, as well as TEAH, are classified as corrosive to skin. Both are also classified as irritating to eyes with risk of serious damage to eyes, in accordance with the CLP Regulation.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Skin irritation/corrosion

Two acute dermal toxicity tests are performed with the registered substance. In both studies, necrosis of the skin was observed.

The substance analogue TMAH has been established to be corrosive, category 1B. An acute dermal irritation /corrosion test according to OECD 404 with 2.38% TMAH in water was performed under GLP circumstances and an in vitro study according to OECD 435 with tetramethylammonium hydroxide pentahydrate.

In view of the high pH of TEAH aqueous solutions due to the hydroxide ion, a similar effect on skin is expected, thus TEAH, as well as the registered substance (TEAH 35% in water), are also considered to be corrosive to skin, category 1B.

Eye irritation/corrosion

Any eye irritation study is waived based on the corrosiveness of the registered substance to the skin and based on the strong alkalinity of the substance.


Justification for selection of skin irritation / corrosion endpoint:
No key study was selected, the endpoint conclusion is derived by weight of evidence.

Justification for selection of eye irritation endpoint:
The study is waived, based on the corrosive properties of the substance.

Effects on skin irritation/corrosion: corrosive

Effects on eye irritation: corrosive

Justification for classification or non-classification

The substance analogue TMAH has been established to be corrosive, category 1B. In view of the high pH of TEAH aqueous solutions due to the hydroxide ion, a similar effect on skin is expected, thus TEAH, as well as the registered substance (TEAH 35% in water), are also considered to be corrosive to skin, category 1B.

In accordance with section 3.3.2.3 of Annex 1 of the CLP Regulation, the registered substance, as well as TEAH, are also classified as irritating to eyes with risk of serious damage to eyes.