Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Reliable studies investigating the acute toxicity of sodium 2-biphenylate (CAS 132-27-4) are available for several freshwater as well as marine organisms. Reliable data on the acute toxicity to freshwater invertebrates and microorganisms as well as chronic toxicity studies are not available. To fulfil the information requirements read-across to the structurally related substance 2-phenylphenol (CAS 90-43-7) was conducted in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006. In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular for aquatic toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across). According to Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 substances can be considered similar if their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity.

The source substance 2-phenylphenol (CAS 90-43-7) is the conjugate acid of sodium 2-biphenylate. Under environmentally relevant conditions sodium 2-biphenylate will dissociate on contact with water forming NaOH and 2-phenylphenol. Consequently dissociation of sodium 2-biphenylate to 2-phenylphenol is also relevant for aquatic toxicity testing. Testing of sodium 2-biphenylate will include the formation of 2-phenylphenol and a differentiation between the effect of the substances is not feasible. The target and the source substance are expected to have a similar environmental fate and ecotoxicity profile due to the comparable physico-chemical properties of both substances. The target and the source substance are characterised by a low vapour pressure (1.2 and 0.474 Pa at 20 °C respectively) and low adsorption potential (log Koc <3). The water solubility of the source substance Sodium 2-biphenylate is > 1000 g/L at pH 13.6 and 20 °C. However, as indicated by the measured dissociation constant for the substance (pKa(2-phenylphenol) = 9.5) Sodium 2-biphenylate will dissociate forming 2-phenylphenol under environmental relevant pH (pH 5 - 9). The measured water solubility of 2-phenylphenol ranged from 0.53 – 0.64 mg/L (pH 5-9 at 20°C).

Studies on the acute toxicity of sodium 2-biphenylate (CAS 132-27-4) are available for the freshwater fish species Oncorhynchus mykiss and Lepomis macrochirus, as well as for the non-standard freshwater organisms Anabaena flos-aquae (blue-green algae)and Navicula pelliculosa (diatom)Data on marine organisms are available for the saltwater fish species Cyprinodon variegatus, the marine invertebrate Americamysis bahia and the marine diatom Skeletonema costatum.

The key information for evaluation of acute freshwater toxicity was obtained from an acute toxicity test with the target substance sodium 2-biphenylate (CAS 132-27-4) determining a LC50 (96 h) of 2.6 mg a.i./L (arith. mean meas.) for Oncorhynchus mykiss.

Acute toxicity testing with the target substance sodium 2-biphenylate on marine organisms determined a LC50 (96 h) of 5.1 mg a.i./L (arith.mean meas.) for Cyprinodon variegatus. A LC50 (96 h) of 0.32 mg a.i./L (arith.mean meas.) was determined for Americamysis bahia. Based on the growth rate an EC50 (72 h) of 7.4 mg a.i./L (arith.mean meas.) was determined for Skeletonema costatum (NOErC (72 h): 2.4 mg a.i./L (arith.mean meas.)).

The assessment of the acute toxicity to aquatic invertebrates and algae was based on data available for the source substance 2-phenylphenol. Data on the chronic toxicity of the source substance 2-phenylphenol were assessed to allow a more realistic PNEC calculation.

The assessment of short-term toxicity to aquatic invertebrates is based on a LC50 of 2.7 mg a.i./L (nominal) for Daphnia magna. The assessment of toxicity to algae is based on a study on Pseudokirchneriella subcapitata. Based on growth rate an EC50 (72 h) of 3.57 mg a.i./L(arith.mean meas.)was determined (corresponding NOEC (72 h) = 0.468 mg a.i./L(arith.mean meas.)).

The evaluation of long-term toxicity is based on a chronic toxicity study on Daphnia magna. A NOEC (21 d) of 0.006 mg a.i./L (geom. mean) based on the reproduction of D. magna was observed.  In a long-term toxicity study on Pimephales promelasan overall NOEC (21 d) of 0.036 mg a.i./L(arith.mean meas.)was reported. 

The evaluation of the toxicity to STP organisms is based on data available for the source substance 2-phenylphenol. An inhibition of microbial activity was determined resulting in an EC50 (3 h) of 62.2 mg/L.

Based on the available data the target substance sodium 2-biphenylate is considered as acutely and chronically toxic to aquatic organisms.