α-bromo-m-toluonitrile

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species, other

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:

Data is from computational model developed by USEPA

Qualifier:

according to guideline

Guideline:

other: Modeling database

Principles of method if other than guideline:

Prediction done using BCFBAF (v3.01) model

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of the test material: α-bromo-m-toluonitrile
- IUPAC name: 3-(bromomethyl)benzonitrile
- Molecular formula: C8H6BrN
- Molecular weight: 196.046 g/mol
- Smiles: N#Cc1cc(CBr)ccc1
- Inchi: 1S/C8H6BrN/c9-5-7-2-1-3-8(4-7)6-10/h1-4H,5H2
- Substance type: Organic
- Physical state : Solid crystalline powder (Off white)

Radiolabelling:

not specified

Vehicle:

not specified

Test organisms (species):

other: Fish

Route of exposure:

aqueous

Test type:

other: estimation

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:

18.66 L/kg

Basis:

whole body w.w.

Calculation basis:

other: estimated

Remarks on result:

other: Non-bioaccumulative

BCFBAF Program (v3.01) Results:

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

SMILES : C(#N)c(cccc1CBr)c1

CHEM : Benzonitrile, 3-(bromomethyl)-

MOL FOR: C8 H6 Br1 N1

MOL WT : 196.05

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

Summary Results:

Log BCF (regression-based estimate): 1.27 (BCF = 18.7 L/kg wet-wt)

Biotransformation Half-Life (days) : 0.273 (normalized to 10 g fish)

Log BAF (Arnot-Gobas upper trophic): 1.35 (BAF = 22.4 L/kg wet-wt)

Log Kow (experimental): not available from database

Log Kow used by BCF estimates: 2.43

Equation Used to Make BCF estimate:

Log BCF = 0.6598 log Kow - 0.333 + Correction

Correction(s): Value

No Applicable Correction Factors

Estimated Log BCF = 1.271 (BCF = 18.66 L/kg wet-wt)

Validity criteria fulfilled:

not specified

Conclusions:

Using BCFBAF Program (v3.00) model of EPI suite 2017 the estimated bio concentration factor (BCF) for 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) is 18.66 L/kg wet-wt at 25 deg. c which does not exceed the bioconcentration threshold of 2000. Therefore it is concluded that test chemical 3-(bromomethyl)benzonitrile is non bioaccumulative in food chain.

Executive summary:

Using BCFBAF Program (v3.00) model of EPI suite 2017 the estimated bio concentration factor (BCF) for 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) is 18.66 L/kg wet-wt at 25 deg. c which does not exceed the bioconcentration threshold of 2000. Therefore it is concluded that test chemical 3-(bromomethyl)benzonitrile is non bioaccumulative in food chain.

Description of key information

Using BCFBAF Program (v3.00) model of EPI suite 2017 the estimated bio concentration factor (BCF) for 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) is 18.66 L/kg wet-wt at 25 deg. c which does not exceed the bioconcentration threshold of 2000. Therefore it is concluded that test chemical 3-(bromomethyl)benzonitrile is non bioaccumulative in food chain.

Key value for chemical safety assessment

BCF (aquatic species):

18.66 L/kg ww

Additional information

Various predicted data studies for target chemical and two different experimental studies for its structurally similar read across chemicals have been conducted to determine bioaccumulation factor are summarized below.

The first weight of evidence study was done by using BCFBAF Program (v3.00) model of Estimation Program Interface (EPI suite 2017) In this study the bio concentration factor (BCF) for target chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) was estimated to be 18.66 L/kg wet-wt at 25 deg. c.

 

Another weight of evidence study was done by using Bio-concentration Factor (v12.1.0.50374) module of Advanced Chemistry Development/I-lab predictive module (2017) in this study the Bio-concentration Factor at range pH 1-14  of the chemical 3-(bromomethyl)benzonitrile estimated to be 36.3 dimensionless.

Next weight of evidence study was done from SciFinder database of American Chemical Society (ACS, 2017) in this study the Bioconcentration factor (BCF) for test chemical 3-(bromomethyl)benzonitrile was predicted in aquatic organisms at pH 1-10 and temperature 25 °C .The Bioconcentration factor (BCF) of test substance 3-(bromomethyl)benzonitrile at pH 1-10 and temperature 25 °C was estimated to be 29.3 dimensionless.

 

Further the Bioconcentration factor (BCF) for test chemical 3-(bromomethyl)benzonitrile was predicted in aquatic organisms by Chemspider- ACD/PhysChem Suite of Royal Society of Chemistry (RCS, 2017) at pH 5.5 and pH 7.4.The Bioconcentration factor (BCF) of test substance 3-(bromomethyl)benzonitrile at pH 5.5 and pH 7.4 was estimated to be 46.82 dimensionless. 

Last predicted data study was done from CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application)  V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical)  the bioaccumulation i.e BCF for test substance 3-(bromomethyl)benzonitrile was estimated to be 7.73 dimensionless . The predicted BCF result was based on the 5 OECD principles.

 

Next weight of evidence study was experimental study done from authoritative database (HSDB, 2017) for structurally similar read across chemical. The BCF value of read across chemical 1-(bromomethyl)-3-methylbenzene (CAS no. 620-13-3) estimated was 85 dimensionless by using log Kow of 3.43 and regression derived equation and it is far less than 2000 criteria so it is concluded that read across chemical 1-(bromomethyl)-3-methylbenzene is non bioaccumulative.

 

Similarly one more experimental study has been conducted from same source as mentioned in above study for another read across chemical. In this study the BCF value of read across 2-phenylacetonitrile (CAS no. 140-29-4) estimated was 9.0 dimensionless by using log Kow of 1.56 and regression derived equation and it is far less than 2000 criteria so it is concluded that read cross chemical 2-phenylacetonitrile is non bioaccumulative.

On the basis of above results for target chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) (From EPI suite, ACD labs, Sci Finder database, CompTox Chemistry Dashboard and ChemSpider, 2017) it can be concluded that the BCF value of test substance 3-(bromomethyl)benzonitrile ranges from 7.73 to 46.82 dimensionless which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 3-(bromomethyl)benzonitrile is not expected to bioaccumulate in the food chain.