2-(4-aminoanilino)-5-nitrobenzenesulphonic 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:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3 with log kow as the primary discriptors.

GLP compliance:

not specified

Specific details on test material used for the study:

Name of test material: 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid
Molecular formula: C12H11N3O5S
Molecular weight: 309.301 g/mol
Physical Appearance: Solid
Smiles notation : O=S(=O)(O)c1c(Nc2ccc(N)cc2)ccc([N+]([O])=O)c1
InChl : GSITZZUEHIPPMH-UHFFFAOYSA-N

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

113.18 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" )  and ("d" and ( not "e") )  )  and "f" )  and ("g" and "h" )  )

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 SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Primary aromatic amine by DNA binding by OECD

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Strong binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OASIS v.1.3

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide Side Chain OR Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroaniline Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR SN1 OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroaniline Derivatives OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids by DNA binding by OASIS v.1.3

Domain logical expression index: "f"

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: "g"

Parametric boundary:The target chemical should have a value of log Kow which is >= -2.08

Domain logical expression index: "h"

Parametric boundary:The target chemical should have a value of log Kow which is <= 1.8

Validity criteria fulfilled:

not specified

Conclusions:

Using OECD QSAR toolbox version 3.3 the median Effective concentration (EC50) value for test chemical 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid on Desmodesmus subspicatus in a 72 hour study was estimated to be 113.18 mg/L on the basis of effects on growth rate.

Executive summary:

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic algae and cyanobacteria was predicted for target substance 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (CAS no. 91-29-2). EC50 value was estimated to be 113.18 mg/l for Desmodesmus subspicatus for 72 h duration. Based on this value it can be concluded that the substance -[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (CAS no. 91-29-2) is likely to be non toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Description of key information

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic algae and cyanobacteria was predicted for target substance 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (CAS no. 91-29-2). EC50 value was estimated to be 113.18 mg/l for Desmodesmus subspicatus for 72 h duration. Based on this value it can be concluded that the substance -[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (CAS no. 91-29-2) is considered to be non toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

113.18 mg/L

Additional information

Three studies including predicted data from validated tools and experimental data from authorative database for short term toxicity to aquatic algae endpoint of test chemical 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (Cas no. 91-29-2) with relevant read across which is close to target using log Kow as primary descriptor were summarised as follows:

 

First prediction using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, which indicate the short term toxicity on aquatic algae and cyanobacteria was predicted for target substance 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (Cas no. 91-29-2). EC50 value was estimated to be 113.18 mg/l for Desmodesmus subspicatus for 72 h duration. 

Similarly, prediction by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program suggest on the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 11619 mg/l for green algae for 96 h duration.

Both predicted results for target assist by experimental data of read across chemical 2-methoxyaniline (Cas no.90-04-0) from authorative database J-check;2017 which indicate Short term toxicity to green algae study was carried out for 72 hrs.The study was based on the effects of the test compound 2-methoxyaniline (CAS no. 90-04-0) on green algae in a static fresh water system. Based on areas under the growth curves effects the 72 hr NOEC value was determined to be 7.5 mg/l.

Thus based on the both predicted effect concentrations which is in the range 113.18 mg/l to 11619 and NOEC value of read across i.e 7.5 mg/l which come to the conclusion that test substance 2-[(4-aminophenyl) amino]-5-nitrobenzenesulfonic acid (Cas no. 91-29-2) was likely to be non toxic to aquatic algae as it not exceed the classification criteria of aquatic toxicity as per the CLP regulation.