N,N-diethyl-p-(phenylazo)aniline

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

Data is from OECD QSAR toolbox version 3.3 and the QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: Estimated data

Version / remarks:

No data

Deviations:

not specified

Principles of method if other than guideline:

Prediction was done using the OECD QSAR toolbox version 3.3.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: 4-(Diethylamino)azobenzene
- Molecular formula: C16H19N3
- Molecular weight: 253.347 g/mol
- Smiles notation: c1(N(CC)CC)ccc(\N=N\c2ccccc2)cc1
- InChl: 1S/C16H19N3/c1-3-19(4-2)16-12-10-15(11-13-16)18-17-14-8-6-5-7-9-14/h5-13H,3-4H2,1-2H3/b18-17+
- Substance type: Organic
- Physical state: Solid

Analytical monitoring:

not specified

Details on sampling:

No data available

Vehicle:

not specified

Details on test solutions:

No data available

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

No data available

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

No data available

Post exposure observation period:

No data available

Hardness:

No data available

Test temperature:

24±2°C

pH:

7.8-8.8

Dissolved oxygen:

No data available

Salinity:

No data available

Conductivity:

No data available

Nominal and measured concentrations:

Nominal

Details on test conditions:

No data available

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

11.093 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: toxic

Details on results:

No data available

Results with reference substance (positive control):

No data available

Reported statistics and error estimates:

No data available

The prediction was based on dataset comprised from the following descriptors: EC50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

(((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and "j" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo OR Overlapping groups by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aliphatic Nitrogen, one aromatic attach [-N] OR Amino, aliphatic attach [-N<] OR Aromatic Carbon [C] OR Azo [-N=N-] OR Olefinic carbon [=CH- or =C<] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Amine OR Aromatic compound OR Azo compound OR Tertiary amine OR Tertiary mixed amine by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non binder, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Non binder, MW>500 OR Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Group 14 - Carbon C AND Group 15 - Nitrogen N by Chemical elements

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Group 16 - Oxygen O OR Group 16 - Sulfur S by Chemical elements

Domain logical expression index: "i"

Parametric boundary:The target chemical should have a value of log Kow which is >= 3.18

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of log Kow which is <= 7.38

Validity criteria fulfilled:

not specified

Conclusions:

The EC50 value was estimated to be 11.092mg/l when 4-(Diethylamino)azobenzene exposed to Desmodesmus subspicatus for 48hrs.

Executive summary:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)was predicted for 4-(Diethylamino)azobenzene (2481 -94 -9). The EC50 value was estimated to be 11.092mg/l when  4-(Diethylamino)azobenzene exposed to Desmodesmus subspicatus for 48hrs.

Description of key information

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)was predicted for 4-(Diethylamino)azobenzene (2481 -94 -9). The EC50 value was estimated to be 11.092mg/l when  4-(Diethylamino)azobenzene exposed to Desmodesmus subspicatus for 48hrs.

Key value for chemical safety assessment

EC50 for freshwater algae:

11.092 mg/L

Additional information

Based on the various experimental data and prediction data for the target chemical and read across chemicals have been reviewed to determine the toxic nature of target chemical 4-(Diethylamino)azobenzene (2481 -94 -9). The studies are as mention below:

In the first weight of evidence study for 4-(Diethylamino)azobenzene (2481 -94 -9), Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)was predicted for 4-(Diethylamino)azobenzene (2481 -94 -9). The EC50 value was estimated to be 11.092mg/l when  4-(Diethylamino)azobenzene exposed to Desmodesmus subspicatus for 48hrs.

Similarly in the second weight of evidence study for the RA chemical (119 -64 -2) tetralin, from OECD SIDS report and IUCLID dataset 2000.Toxicity of tetralin on the growth of freshwater algae Scenedesmus subspicatus for 72hrs was syudied. Test was performed in Erlenmeyer flasks in static system. 1 g test substance/l was stirred in deionized water for 18 hours and filtered. The resulting concentration was 63 mg/l. The maximum concentration tested was 17 mg/l. No vehicle or solvent was used. Toxicity was checked in the interval of 24 hrs, at Six different concentration 1.20; 2.0; 3.6; 6.0; 10.0; 17.0 mg/l (nominal) and 0 mg/l for control.Based on the growth rate of Scenedesmus subspicatus (Algae) due to the 1,2,3,4-Tetrahydronaphthalene the EC10, EC50, EC90 was 5.3 mg/l, 11 mg/l and 25 mg/l. But on the basis of of biomass the EC10, EC50, EC90 was 3.8 mg/l, 7mg/l, 13mg/l. and the NOEC was 3.6mg/l. Based on the EC50 (11 mg/l) growth rate of Scenedesmus subspicatus (Algae) due to the 1, 2, 3, 4-Tetrahydronaphthalene, chemical was toxic and can be consider in chronic category 3 as per the CLP classification criteria.

Based on the various experimental data and prediction data for the target chemical and read across chemicals 1, 2, 3, 4-Tetrahydronaphthalene, chemical was toxic

and can be consider in chronic category 3 as per the CLP classification criteria.