Sodium 3-(p-anilinophenylazo)benzenesulphonate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

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 QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: predicted data

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 (as cited in study report): METANIL YELLOW (Sodium 3-(p-anilinophenylazo)benzenesulphonate)
- Molecular formula (if other than submission substance): C18 H14 N3 O3 S1 Na1
- Molecular weight (if other than submission substance): 375.38 mg/l
- Smiles notation (if other than submission substance): c1ccc(cc1)Nc2ccc(cc2)N=Nc3cccc(c3)S(=O)(=O)O([Na])
- InChl (if other than submission substance): NYGZLYXAPMMJTE-ANVLNOONSA-M
- Substance type: Organic
- Physical state: Solid

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

6.55 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

other: Intoxication

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" )  and "c" )  and "d" )  and "e" )  and ("f" and "g" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Aromatic azo by DNA binding by OECD

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as AN2 AND AN2 >> Michael-type addition to quinoid structures  AND AN2 >> Michael-type addition to quinoid structures  >> N-Substituted Aromatic Amines by Protein binding by OASIS v1.4

Domain logical expression index: "c"

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: "d"

Similarity boundary:Target: O=S(=O)(c1cccc(N=Nc2ccc(Nc3ccccc3)cc2)c1)O{-}.[Na]{+}
Threshold=40%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "e"

Similarity boundary:Target: O=S(=O)(c1cccc(N=Nc2ccc(Nc3ccccc3)cc2)c1)O{-}.[Na]{+}
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "f"

Parametric boundary:The target chemical should have a value of log Kow which is >= 0.137

Domain logical expression index: "g"

Parametric boundary:The target chemical should have a value of log Kow which is <= 2.84

Validity criteria fulfilled:

not specified

Conclusions:

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, the short term toxicity on aquatic invertebrates was predicted for Sodium 3-(p-anilinophenylazo)benzenesulphonate (Cas no. 587-98-4). Effect concentration i.e EC50 value was estimated to be 6.55 mg/l for Desmodesmus subspicatus for 72 hrs duration. It was concluded that the Sodium 3-(p-anilinophenylazo)benzenesulphonate (Cas no. 587-98-4) was likely to be toxic to aquatic invertebrates, hence it can be considered to be classified as per the CLP classification criteria for aquatic environment.

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, the short term toxicity on aquatic invertebrates was predicted for Sodium 3-(p-anilinophenylazo)benzenesulphonate (Cas no. 587-98-4). Effect concentration i.e EC50 value was estimated to be 6.55 mg/l for Desmodesmus subspicatus for 72 hrs duration. It was concluded that the Sodium 3-(p-anilinophenylazo)benzenesulphonate (Cas no. 587-98-4) was likely to be toxic to aquatic invertebrates, hence it can be considered to be classified as per the CLP classification criteria for aquatic environment.

Description of key information

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the 5 closest read across substances, the short term toxicity on aquatic invertebrates was predicted for Sodium 3-(p-anilinophenylazo)benzenesulphonate (CAS 587 -98 -4). Effect concentration i.e EC50 value was estimated to be 6.55 mg/l for Daphnia magna for 48 hrs duration. Based on the effect value, Sodium 3-(p-anilinophenylazo)benzenesulphonate (CAS 587 -98 -4) was likely to be toxic to aquatic invertebrates, hence it can be considered to be“aquatic chronic 2”as per the CLP classification criteria for aquatic environment.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

6.55 mg/L

Additional information

Four studies including predicted data from validated tools and experimental data from peer reviewed journal and authorative database for short term aquatic invertebrate’s endpoint of test chemical Sodium 3-(p-anilinophenylazo)benzenesulphonate (CAS 587 -98 -4) with relevant read across which is close to target using log Kow as primary descriptor were summarised as follows:

 

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the 5 closest read across substances, the short term toxicity on aquatic invertebrates was predicted for Sodium 3-(p-anilinophenylazo)benzenesulphonate (CAS 587 -98 -4). Effect concentration i.e EC50 value was estimated to be 6.55 mg/l for Daphnia magna for 48 hrs duration. Based on the effect value, Sodium 3-(p-anilinophenylazo)benzenesulphonate (CAS 587 -98 -4) was likely to be toxic to aquatic invertebrates.

 

Similar prediction by Using battery model of Danish QSAR, 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 the LC50 value for short term toxicity to aquatic invertebrates was predictedthe toxicity of Sodium 3-(p-anilinophenylazo)benzenesulphonate EC50 estimated to be 2.52 mg/l to Daphnia magna when exposed for 48h.

 

Above both predicted results of target assist by experimental result of read across chemical Fluometuron (Cas no.2164-17-2) fromsecondary source EPA Office of Pesticides Program Database which suggest the Short-term toxicity to aquatic invertebrates test was carried out to study the effects of Fluometuron on Americamysis bahia under flow through and saltwater conditions. Mortality effect were measured. The Lethal concentration (LC50) for Americamysis bahia when exposed to Fluometuron for 96 h is 6.8 mg/l.

Thus based on the all available effect concentrations which is in the range of 2.52 mg/l to 6.8 mg/l for target and read across chemicals and by applying weight of evidence approach it can be concluded that test substance Sodium 3-(p-anilinophenylazo)benzenesulphonate (Cas No. 587 -98 -4) is toxic to aquatic invertebrates, hence it can be considered classified under Aquatic chronic category 2 as per the CLP regulation.