4-tert-butylbenzoic acid

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Persistence:

PTBBA is not readily biodegradable (Shell Research Limited, 1984a; cited in European Union Risk Assessment Report, 4-TERT-BUTYLBENZOIC ACID, RISK ASSESSMENT, July 2009, FINAL APPROVED VERSION, page 34), but other data available indicate that PTBBA might be inherently biodegradable (see chapter 3.1.3). As the present data cannot be used to judge whether the substance is inherently biodegradable or not, the screening P-criterion can be considered to be fulfilled.

Bioaccumulation:

For PTBBA, no experimental results on bioaccumulation are available. The octanol-water partitioning coefficient for the undissociated substance (logKow = 3.4) is below the screening criterion logKow of 4.5. As PTBBA is present in the environmentally relevant pH-range mainly in ionized form, bioaccumulation potential can be expected to be low. It can thus be concluded that PTBBA does not fulfil the screening B-criterion (cited in European Union Risk Assessment Report, 4-TERT-BUTYLBENZOIC ACID, RISK ASSESSMENT, July 2009, FINAL APPROVED VERSION, page 34).

Toxicity:

Only acute data on the aquatic ecotoxicity of PTBBA are available (see chapter 3.2.1 of the European Union Risk Assessment Report

). Information on the toxicity of organisms in other compartments has not been presented. The lowest acute effect value (for goldfish; 96h-LC50 = 4 mg l-1) is higher than the T-screening criterion of 0.1 mg l-1 (cited in European Union Risk Assessment Report, 4-TERT-BUTYLBENZOIC ACID, RISK ASSESSMENT, July 2009, FINAL APPROVED VERSION, page 34).

The substance PTBBA is classified in accordance to RAC (Opinion proposing harmonised classification and labelling at Community level of 4-tert-butylbenzoic acid, ECHA/RAC/CLH-O-0000001579-64-01/F, Adopted 21 February 2011) and Annex VI of the Regulation (EC) No 1272/2008 (3rd ATP) as Repr. 1B, STOT RE 1 and Acute Tox. 4 (H360F, H372, H302, respectively). According to the Guidance Document on PBT Assessment (R.11, Nov. 2012, chapter R.11.1.3.3

Toxicity assessment (T), p. 35) PTBBA fulfils the T criterion because of the classifications as Repr. 1B and STOT RE 1.

Overall result:

According to Annex XIII of the Regulation (EC) No 1907/2006 (REACH) a substance is PBT if the three criteria, i. e. persistence, bioaccumulative and toxic are fulfiled. For the substance PTBBA two of the three criteria are fulfiled (P, T), thus the substance can be considered as no PBT.