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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Trimethylaluminium is classified as Pyr. Liquid 1, Water React. Flam. Gas 1 and Skin Corr. 1B. Therefore, the substance ignites upon exposure to air, reacts violently with water and causes severe burns to the skin and eyes. Consequently, it is not technically feasible to conduct toxicological studies with this substance.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Trimethylaluminium is classified as Pyr. Liquid 1, Water React. Flam. Gas 1 and Skin Corr. 1B. Therefore, the substance ignites upon exposure to air, reacts violently with water and causes severe burns to the skin and eyes. Consequently, it is not technically feasible to conduct toxicological studies with this substance.

Trimethylaluminium reacts spontaneously with water to produce aluminium hydroxide and methane or methanol and reacts spontaneously with air; the products of complete combustion being aluminium oxide, carbon dioxide and water. Therefore, the toxicological effects of aluminium oxide and aluminium hydroxide need to be considered when evaluating the effects of long-term exposure to trimethylaluminium.

Aluminium oxide and aluminium hydroxide are not classified for human health effects. These substances are of low acute oral toxicity with a very low oral bioavailability. Due to their insolubility in water, it is predicted that aluminium oxide and aluminium hydroxide will not be absorbed through the skin. Following inhalation exposure to aluminium oxide and aluminium hydroxide, the available data indicate that transfer of aluminium to the systemic circulation is low. There is no conclusive evidence that exposure to aluminium oxide or aluminium hydroxide leads to skin, eye or respiratory irritation effects. These aluminium salts also appear to have low sensitising potential. There are also no data to suggest that aluminium oxide and aluminium hydroxide are mutagenic or carcinogenic or that they have adverse reproductive/developmental effects.

Justification for classification or non-classification

TMA is not classified for acute toxicity as it rapidly converts to aluminium oxide or aluminium hydroxide; both these substances are not classified.