5-amino-2-anilinobenzenesulphonic acid

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:

The supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Prediction is done using QSAR Toolbox version 3.4

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.4

GLP compliance:

no

Specific details on test material used for the study:

- Name of test material (as cited in study report): Benzenesulfonic acid, 5-amino-2-(phenylamino)-
- Molecular formula: C12 H12 N2 O3 S
- Molecular weight : 264.304 g/mol
- Smiles notation: O=S(=O)(O)c1c(Nc2ccccc2)ccc(N)c1
- InChl: 1S/C12H12N2O3S/c13-9-6-7-11(12(8-9)18(15,16)17)14-10-4-2-1-3-5-10/h1-8,14H,13H2,(H,15,16,17)
- Substance type: Organic
- Physical state: solid

Analytical monitoring:

not specified

Details on sampling:

not specified

Vehicle:

not specified

Details on test solutions:

not specified

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

not specified

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Hardness:

not specified

Test temperature:

22.3-24°C

pH:

7.36-7.93

Dissolved oxygen:

not specified

Salinity:

not specified

Conductivity:

not specified

Nominal and measured concentrations:

not specified

Details on test conditions:

not specified

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

138.006 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

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" or "e") and("f" and(not "g")) ) and "h") and "i") and("j" and "k") )

Domain logical expression index: "a"

Referential boundary:The target chemical should be classified as Anilines (Acute toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "b"

Referential boundary:The target chemical should be classified as Aniline AND Aryl AND Sulfonic acid by Organic Functional groups

Domain logical expression index: "c"

Referential boundary:The target chemical should be classified as Aniline AND Aryl AND Overlapping groups AND Sulfonic acid by Organic Functional groups (nested)

Domain logical expression index: "d"

Referential boundary:The target chemical should be classified as Aliphatic Nitrogen, one aromatic attach [-N] AND Aliphatic Nitrogen, two aromatic attach [-N-] AND Aromatic Carbon [C] AND Hydroxy, sulfur attach [-OH] AND Miscellaneous sulfide (=S) or oxide (=O) AND Nitrogen, two or tree olefinic attach [>N-] AND Olefinic carbon [=CH- or =C<] AND Suflur {v+4} or {v+6} AND Sulfinic acid [-S(=O)OH] AND Sulfonate, aromatic attach [-SO2-O] by Organic functional groups (US EPA)

Domain logical expression index: "e"

Referential boundary:The target chemical should be classified as Amine AND Aromatic compound AND Primary amine AND Primary aromatic amine AND Secondary amine AND Secondary aromatic amine AND Sulfonic acid AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "f"

Referential boundary:The target chemical should be classified as No alert found by Protein binding alerts for Chromosomal aberration by OASIS v.1.2

Domain logical expression index: "g"

Referential boundary:The target chemical should be classified as Acylation OR Acylation >> Acylation involving an activated (glucuronidated) carboxamide group OR Acylation >> Acylation involving an activated (glucuronidated) carboxamide group >> Carboxylic Acid Amides OR Acylation >> Direct acylation involving a leaving group OR Acylation >> Direct acylation involving a leaving group >> Carboxylic Acid Amides OR AN2 OR AN2 >> Michael addition to the quinoid type structures OR AN2 >> Michael addition to the quinoid type structures >> Carboxylic Acid Amides OR AN2 >> Michael addition to the quinoid type structures >> Substituted Anilines by Protein binding alerts for Chromosomal aberration by OASIS v.1.2

Domain logical expression index: "h"

Referential boundary:The target chemical should be classified as Class 5 (Not possible to classify according to these rules) by Acute aquatic toxicity classification by Verhaar (Modified) ONLY

Domain logical expression index: "i"

Referential boundary:The target chemical should be classified as Very fast by Bioaccumulation - metabolism half-lives ONLY

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of log Kow which is >= -3

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.423

Validity criteria fulfilled:

not specified

Conclusions:

The median Effective concentration (EC50) value for Benzenesulfonic acid, 5-amino-2-(phenylamino)- on Desmodesmus subspicatus in a 72 hour study was estimated to be 138.0 mg/L on the basis of effects on growth rate.

Executive summary:

72 hrs aquatic toxicity study was predicted to assess toxic effects of the test compound Benzenesulfonic acid, 5-amino-2-(phenylamino)-(CAS no. 91 -30 -5) and the result were predicted. The study was based on the effects of the test compound on Desmodesmus subspicatus in a static fresh watersystem. The predicted data suggests the effective concentration (EC50) for thetest compound Benzenesulfonic acid, 5-amino-2- (phenylamino)-(CAS no. 91 -30 -5) was estimated to be 138.0 mg/l on the basis of growth rate. Thus, based on this value, it can be concluded that the test chemical Benzenesulfonic acid, 5-amino-2-(phenylamino)- can be considered asnon-toxic to aquatic organismsand thus cannot be classified as hazardousas per the CLP criteria.

Description of key information

72 hrs aquatic toxicity study was predicted to assess toxic effects of the test compound Benzenesulfonic acid, 5-amino-2-(phenylamino)- (CAS no. 91 -30 -5) and the result were predicted (SSS QSAR Prediction Model, 2016). The study was based on the effects of the test compound on Desmodesmus subspicatus in a static fresh watersystem. The predicted data suggests the effective concentration (EC50) for the test compound Benzenesulfonic acid, 5-amino-2- (phenylamino)- (CAS no. 91 -30 -5) was estimated to be 138.0 mg/l on the basis of growth rate.

Key value for chemical safety assessment

EC50 for freshwater algae:

138 mg/L

Additional information

Various predicted data for the target chemical Benzenesulfonic acid, 5-amino-2-(phenylamino)- (CAS No. 91-30-5) and the study for its read across substancewere reviewed to summarize the following information:

 

72 hrs aquatic toxicity study was predicted to assess toxic effects of the test compound Benzenesulfonic acid, 5-amino-2-(phenylamino)- (CAS no. 91 -30 -5) and the result were predicted (SSS QSAR Prediction Model, 2016). The study was based on the effects of the test compound on Desmodesmus subspicatus in a static fresh watersystem. The predicted data suggests the effective concentration (EC50) for the test compound Benzenesulfonic acid, 5-amino-2- (phenylamino)- (CAS no. 91 -30 -5) was estimated to be 138.0 mg/l on the basis of growth rate.

 

Based on the QSAR prediction done using the EPI Suite ECOSAR version 1.10 (EPI Suite, 2016), the 96 hours EC50 was estimated to be 18645.9 mg/l on green algae for substance Benzenesulfonic acid, 5-amino-2-(phenylamino)- (CAS no. 91 -30 -5) with growth inhibition effects.

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the read across substance Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (CAS no. 3567-66-6) according to OECD Guideline 201 (ABITEC study report, Sustainability Support Services (Europe) AB, Report no. 452/16, 2016). The stock solution (200 mg/L) was prepared by dissolving dark red powder in OECD growth medium. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Conc. of read across chemical used for the study was 12.5, 25, 50, 100, and 200 mg/L, respectively. The test was performed under static conditions in a static fresh water system at a temp. of 23±2°C. Initial cell density of test organism used was 5x10(3) cells/ml. Determination of cell counting involve the use of microscope with counting chamber Cyrus I or electronic particle counter. ErC50 was calculated using non-linear regression by the software Prism 4.0. The median effective concentration (EC50) for the read across substance Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate in Desmodesmus subspicatus was determined to be 330.2 mg/L on the basis of effects on growth rate in a 72 hour study.

Based on the overall reported results for target and its read across substance, it can be concluded that the test substance Benzenesulfonic acid, 5-amino-2-(phenylamino)- can be considered asnon-toxic to aquatic organisms and thus cannot be classified as hazardous as per the CLP criteria.