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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Hydrolysis studies show that isobutyric anhydride added to water rapidly converts to isobutyric acid. Thererfore, isobutyric acid data is being used by read across for most environmental fate and ecotox endpoints.

No data could be identified for the terrestrial toxicity of isobutyric acid.


Waiving argument:

In accordance with column 2 of REACH Annexes IX and X, terrestrial studies do not need to be conducted if direct and indirect exposure of the soil compartment is unlikely.

Direct exposure to soil is not likely, since the substance is not intentionally applied to soil. Indirect exposure to soil is also not likely since the substance is readily biodegradable and has a low adsorption potential (log Koc < 3).

In conclusion no testing is required.

The equilibrium partitioning method will be applied to assess the hazard to soil organisms. In accordance with

column 2 of REACH Annex X, any need for testing should be carefully considered taking into account the large

mammalian dataset that is usually available at this tonnage level.

Exposure of birds is generally only considered for the fish and earthworm food chains following the release of a

substance via a sewage treatment works. It is unlikely that a secondary poisoning risk will be identified for isobutyric

acid since it is readily biodegradable and has a low log Kow below 3.