Diphenylacetic acid

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Estimated data generated using the EPI Suite model developed by the USEPA and PBT profiler

Qualifier:

according to guideline

Guideline:

other: Modelling database

Principles of method if other than guideline:

Prediction done using BCFBAF (v3.00) model and PBT profiler

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report): Diphenylacetic acid
- Molecular formula (if other than submission substance): C14H12O2
- Molecular weight (if other than submission substance): 212.247 g/mol
- Smiles notation (if other than submission substance): C(c1ccccc1)(c1ccccc1)C(O)=O
- InChI: 1S/C14H12O2/c15-14(16)13(11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10,13H,(H,15,16)
- Substance type: Organic
- Physical state: solid

Radiolabelling:

not specified

Vehicle:

not specified

Test organisms (species):

other: Fish

Route of exposure:

aqueous

Test type:

not specified

Water / sediment media type:

natural water: freshwater

Test temperature:

25 deg.C

Reference substance (positive control):

not specified

Key result

Temp.:

25 °C

Type:

BCF

Value:

3.2 L/kg

Basis:

whole body w.w.

Calculation basis:

other: estimated

Remarks on result:

other: Non bioaccumulative

EPI SUITE prediction:

BCFBAF Program (v3.01) Results:

==============================

SMILES : O=C(O)C(c(cccc1)c1)c(cccc2)c2

CHEM : Benzeneacetic acid, .alpha.-phenyl-

MOL FOR: C14 H12 O2

MOL WT : 212.25

--------------------------------- BCFBAF v3.01 --------------------------------

Summary Results:

Log BCF (regression-based estimate): 0.50 (BCF = 3.16 L/kg wet-wt)

Biotransformation Half-Life (days) : 0.368 (normalized to 10 g fish)

Log BAF (Arnot-Gobas upper trophic): 1.84 (BAF = 69.9 L/kg wet-wt)

Log Kow (experimental): 3.09

Log Kow used by BCF estimates: 3.09

Equation Used to Make BCF estimate:

Log BCF = 0.50 (Ionic; Log Kow dependent)

Estimated Log BCF = 0.500 (BCF = 3.162 L/kg wet-wt)

Validity criteria fulfilled:

not specified

Conclusions:

From BCFBAF (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for 1,1-Diphenylacetic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 1,1-Diphenylacetic acid is not expected to bio accumulate in the aquatic environment.

Executive summary:

From BCFBAF (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for 1,1-Diphenylacetic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 1,1-Diphenylacetic acid is not expected to bio accumulate in the aquatic environment.

Description of key information

From BCFBAF (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for 1,1-Diphenylacetic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 1,1-Diphenylacetic acid is not expected to bio accumulate in the aquatic environment.

Key value for chemical safety assessment

BCF (aquatic species):

3.2 L/kg ww

Additional information

Four studies including predicted data from validated models and experimental data from authorative database for bioaccumulation (BCF) endpoint of target chemical 1,1-Diphenylacetic acid (Cas no. 117-34-0) with relevant read across which is structurally similar to target were summarized as follows: 

 

First study from prediction done using BCFBAF (v3.00) model and PBT profiler which indicate the estimated bio concentration factor (BCF) for 1,1-Diphenylacetic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 1,1-Diphenylacetic acid is not expected to bio accumulate in the aquatic environment.

 

Above prediction is supported by data Scifinder database which suggest the Bioconcentration factor (BCF) for target chemical 1,1-Diphenylacetic acid was predicted to be 66.9 at pH 1, 66.8 at pH 2, 65.7 at pH 3, 56.2 at pH 4, 23.0 at pH 5, 3.35 at pH 6, 1.0 at pH range 7-10 and temperature 25 deg.C.Based on the BCF concentration at all range of pH it is concluded that the test chemical 1,1-Diphenylacetic acid is non bioaccumulative in nature as it does not exceed the BCF criteria of 2000. 

Another estimation from Chemspider - ACD/PhysChem Suite indicate the Bioconcentration factor (BCF) for target chemical 1,1-Diphenylacetic acid was estimated to be 33.76 at pH 5.5 and 1.00 at pH 7.4 at temperature 25 deg.C.Based on the BCF concentration at two different pH concluded that the test chemical 1,1-Diphenylacetic acid is non bioaccumulative in nature as it does not exceed the BCF criteria of 2000. 

Above all results for target are further supported by experimental data of read across chemical nicotinic acid (Cas no. 59-67-6) which suggest an estimated BCF value of 3 was calculated in fish for nicotinic acid, using a log Kow of 0.36 and a recommended regression derived equation. This BCF value suggests that the potential for bioconcentration in aquatic organisms (fish) is low. (HSDB database by US EPA; 2017)

Thus based on all available studies for bioaccumulation endpoint concluded that the test substance 1,1-Diphenylacetic acid (Cas no. 117-34-0) is expected to be non Bioaccumulative in aquatic environment.