(3-aminophenyl)urea

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:

The supporting QMRF report has been attached

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: 1-(3-aminophenyl)urea
- Molecular formula: C7 H9 N3 O
- Molecular weight: 151.168 g/mol
- Smiles notation: O=C(Nc1cccc(N)c1)N
- InChl: 1S/C7H9N3O/c8-5-2-1-3-6(4-5)10-7(9)11/h1-4H,8H2,(H3,9,10,11)
- Substance type: Organic
- Physical state: Solid

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

184.58 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: Out of Domain

((((((((((("a" or "b" or "c" )  and "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and ("m" and ( not "n") )  )  and ("o" and ( not "p") )  )  and ("q" and ( not "r") )  )  and ("s" and ( not "t") )  )  and ("u" and "v" )  )

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 Radical AND Radical >> Radical mechanism via ROS formation (indirect) AND Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines AND SN1 AND SN1 >> Nucleophilic attack after metabolic nitrenium ion formation AND SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines by DNA binding by OASIS v.1.3

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as SN1 OR SN1 >> Nitrenium Ion formation OR SN1 >> Nitrenium Ion formation >> Aromatic phenylureas OR SN1 >> Nitrenium Ion formation >> Primary aromatic amine by DNA binding by OECD ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Aromatic phenylureas AND SN1 >> Nitrenium Ion formation >> Primary aromatic amine by DNA binding by OECD ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules by DPRA Cysteine peptide depletion

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as High reactive OR High reactive >> Activated haloarenes OR Low reactive OR Low reactive >> N-substituted aromatic amides by DPRA Cysteine peptide depletion

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No alert found by Protein binding by OASIS v1.3

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Direct acylation involving a leaving group OR Acylation >> Direct acylation involving a leaving group >> N-Acylsulfonamides  OR SNAr OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds >> Activated aryl and heteroaryl compounds by Protein binding by OASIS v1.3

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as No Data by Ultimate biodeg

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as > 100 days OR 1 to 10 days OR 10 to 100 days by Ultimate biodeg

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as No alert found by DNA alerts for AMES, MN and CA by OASIS v.1.3

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Radical OR Radical >> Radical mechanism by ROS formation OR Radical >> Radical mechanism by ROS formation >> Polynitroarenes 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) >> 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 >> Polynitroarenes by DNA alerts for AMES, MN and CA by OASIS v.1.3

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as H-acceptor-path3-H-acceptor AND Primary aromatic amine, hydroxyl amine and its derived esters by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as 1,3-dialkoxy-benzene OR 1-phenoxy-benzene by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as 4,4'-Methylenedianilines/benzidines (Hepatobiliary toxicity) Rank B  OR Anilines (Hemolytic anemia with methemoglobinemia) Rank A OR Anilines (Hepatotoxicity) Rank C OR Thiocarbamates/Sulfides (Hepatotoxicity) No rank by Repeated dose (HESS)

Domain logical expression index: "q"

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

Domain logical expression index: "r"

Referential boundary: The target chemical should be classified as Esters (Acute toxicity) OR Not categorized OR Phenols (Acute toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as Acidic [0,10) AND Basic [0,10) by Ionization at pH = 7.4

Domain logical expression index: "t"

Referential boundary: The target chemical should be classified as Acidic [0,10) by Ionization at pH = 7.4

Domain logical expression index: "u"

Parametric boundary:The target chemical should have a value of log Kow which is >= -0.881

Domain logical expression index: "v"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.311

Validity criteria fulfilled:

not specified

Conclusions:

The short term toxicity on aquatic invertebrates was predicted for 1-(3-aminophenyl)urea (25711-72-2). EC50 value was estimated to be 184.58 mg/l for Daphnia magna for 48 hrs duration. Based on the value, the substance was considered to be non-toxic to aquatic invertebrates and can be considered as not classified as per the CLP regulations.

Executive summary:

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the eight closest read across substances, the short term toxicity on aquatic invertebrates was predicted for 1-(3-aminophenyl)urea (25711-72-2). EC50 value was estimated to be 184.58 mg/l for Daphnia magna for 48 hrs duration. Based on the value, the substance was considered to be non-toxic to aquatic invertebrates and can be considered as not classified as per the CLP regulations.

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 invertebrates was predicted for 1-(3-aminophenyl)urea (25711-72-2). EC50 value was estimated to be 184.58 mg/l for Daphnia magna for 48 hrs duration.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

184.58 mg/L

Additional information

Short term toxicity to aquatic invertebrates for 1-(3-aminophenyl)urea (25711-72-2) was summarised with predicted data for target and by using structural read across studies as follows:

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 invertebrates was predicted for 1-(3-aminophenyl)urea (25711-72-2). EC50 value was estimated to be 184.58 mg/l for Daphnia magna for 48 hrs duration.

In another prediction done 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, the LC 50 value for short term toxicity to aquatic invertebrates was predicted. On the basis of this program, the LC 50 value for short term toxicity to aquatic invertebrates was predicted to be 16472.984 mg/l for 1-(3-aminophenyl)urea in 48 hrs.

Short term toxicity to aquatic invertebrates (Ecotox database, 2017) for read across 4-amino-N-(4-methylpyrimidin-2-yl)benzene sulfonamide(127-79-7) was performed in Daphnia magna for 48 hrs at concentration range from 241-323 mg/l. The test was performed in static fresh water system using < 24 hrs daphnia magna. The hardness and temperature of the experiment was kept at 193 mg/L CaCO3 and 20 degree C. After 48 hrs, the EC 50 value for 4-amino-N-(4-methylpyrimidin-2-yl)benzene sulfonamide(127-79-7) was determined to be 277 mg/l.

From same reference (Ecotox database, 2017) for another read across ammonium 3-amino-2,5-dichlorobenzoate(1076-46-6), short term toxicity to aquatic invertebrates was performed in Daphnia magna for 48 hrs. The test was performed in static fresh water system using < 24 hrs daphnia magna. After 48 hrs, the EC 50 value for ammonium 3-amino-2,5-dichlorobenzoate(1076-46-6) was determined to be >1000 mg/l.

Based on the all the weight of evidences, it was considered that 1-(3-aminophenyl)urea (25711-72-2) was likely to be non-toxic to aquatic organism and can be considered to be not classified for short term toxicity to aquatic invertebrates as per the CLP regulations.