Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability:

Hydrolysis: One study (Harlan 2010), scored as reliability 1 according to Klimisch and selected as a key study, was performed according to OECD guideline n°111. 4 -tert-butylpyrocatechol (4 -TBC) was found to be stable at pH 4.0 at 25°C (t1/2 > 1 year). The half-life time of the degradation of 4 -TBC at 25°C was calculated to be 141 hours (6 days) at pH 7.0. And, 4 -TBC at pH 9.0 is not stable because the half-life was about 3.5 days at 40°C.

Biodegradation:

Ready biodegradability: One study (Tecnologia America Latina, 2002), scored as reliability 2 according to Klimisch and selected as a key study, was performed according to ISO 14593 (similar to OECD guideline n°301). After 28 days, the percentage of degradation was 24.7% based on CO2 evolution. On the basis of this study, 4 -tert-butylpyrocatechol is not readily biodegradable.

Inherent biodegradability: One study in aerobic conditions (Harlan, 2010), scored as reliability 2 according to Klimisch and selected as a key study, was performed according to OECD guideline 302B (Zahn-Wellens test). The biodegradability after 28 days was 91% based on DOC removal. Under the test conditions, 4 -tert-butylpyrocatechol is considered as inherent ultimately biodegradable.

Bioaccumulation:

As no data is available on the bioaccumulation potential of 4 -tert-butylpyrocatechol, the assessment has to be performed based on data on n-octanol/water partition coefficient. The partition coefficient was determined in one experimental study (Processium, 2010), and was given a value of 1.98. Based on this data, 4 -tert-butylpyrocatechol has a low potential for bioaccumulation.

Transport and Distribution:

Adsorption: Two studies are available (Harlan, 2010; Hemwall, 1965). The first of them, scored as reliability 1 according to Klimisch, was selected as a key study. The adsorption coefficient in soil and sewage sludge of 4 -tert-butylpyrocatechol was determined by HPLC method according to OECD guideline n°121. The log Koc of 4 -TBC in soil was found to be 1.37, which is equal to a Koc value of 23.73. The log Koc in sewage sludge could not be determined. 4 -TBC is highly mobile in soils.

The second study, scored as reliability 2 according to Klimisch and selected as supporting study, investigated the possible adsorption of 4 -TBC on various clay minerals. The adsorption of 4 -TBC by clay minerals is initially quite rapid, and then continue for an extended period of time at a relatively slow rate. The adsorption of 4 -TBC by clay from water is quite strong.