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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

 

 

Hydrolysis

Due to its chemical structure and reactivity, isobutyric anhydride will rapidly hydrolyze in contact with water to isobutyric acid. Thererfore, isobutyric acid data is being used by read across for many of the environmental fate and ecotox endpoints.

 

Biodegradation

 

Biodegradation in water: screening test

Isobutyric acid has been shown to be readily biodegradable as combined evidence from two biodegradation tests

1. - test similar to OECD TG 302 B (Hoechst AG, undated; RL2; KS)

2. - test similar to OECD TG 301 E (Henkel KGaA, 1983; RL3; WoE)

 

Biodegradation in water and sediment: simulation test

In accordance with column 2 of REACH Annex IX Nr. 9.2, the study does not need to be conducted as the substance is readily biodegradable.

 

Biodegradation in soil

In accordance with column 2 of REACH Annex IX Nr. 9.2, the study does not need to be conducted as the substance is readily biodegradable.

 

Bioaccumulation

 

Bioaccumulation: aquatic/sediment

In accordance with column 2 of Annex IX, the study does not need to be conducted if the substance has a low potential for bioaccumulation. The log Kow of 1.1 for isobutyric acid (OXEA, 2009) indicates a low potential for bioaccumulation. Therefore and for reasons of animal welfare a fish study is not performed.

Based on an experimental log Kow of 1.1, the log BCF of isobutyric acid was estimated to be 0.5 (BCF = 3.162). In addition, a log BAF (upper trophic) of 0.31 (BAF = 2.06) was calculated using the method of Arnot-Gobas (ECT, 2010). The low BCF/BAF values indicate a low potential of isobutyric acid for bioaccumulation in aquatic and benthic organisms.

 

Transport and Distribution

 

Adsorption/Desorption

In accordance with column 2 of REACH Annex IX Nr. 9.3.3, the study does not need to be conducted as the substance has a low potential for adsorption (log Kow < 3) and is readily biodegradable.

 

As additional information, the Koc of isobutyric acid was estimated to be 44.7 (log Koc = 1.65; charged molecule) (OXEA, 2010) indicating high mobility in soil.