1,4-bis[(2-methylphenyl)amino]anthraquinone

Endpoint summary

Description of key information

Acute oral toxicity: 

Acute oral toxicity dose (LD50) of 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) was predicted based on OECD QSAR toolbox 2953 mg/kg bw and different studies available on structurally similar read across substances sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate (CAS No: 4430-18-6) >2000 mg/kg bw and 1,4-Bis(p-tolylamino)anthraquinone (CAS no: 128-80-3) 3660 mg/kg bw. All these studies concluded that the LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 1,4-bis[(2-methylphenyl)amino]anthraquinone cannot be classified for acute oral toxicity.

Acute Inhalation toxicity: 

1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) has very low vapour pressure (3.02E-11 Pa at 25°C), so the potential for the generation of inhalable vapours is very low. Also the normal conditions of use of this substance will not result in aerosols, particles or droplets of an inhalable size, so exposure to humans via the inhalatory route will be highly unlikely and therefore this end point was considered for waiver.

Acute Dermal toxicity: 

Acute Dermal toxicity dose (LD50) for 1,4-bis[(2-methylphenyl)amino] anthraquinone (CAS no: 6737-68-4) was predicted based on OECD QSAR toolbox 5857 mg/kg bw and different studies available for the structurally similar read across substance sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate (CAS No: 4430-18-6) >2000 mg/kg bw and 1-(2-hydroxyethylamino)-4-(methylamino) anthracene-9,10-dione (CAS no: 2475-46-9) >2000 mg/kg bw. All these studies concluded that the LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 1,4-bis[(2-methylphenyl)amino] anthraquinone cannot be classified for acute dermal toxicity.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

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 predicted using OECD QSAR toolbox version 3.4 and the supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: estimated data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.4

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Specific details on test material used for the study:

Name: 1,4-bis[(2-methylphenyl)amino]anthraquinone
1S/C28H22N2O2/c1-17-9-3-7-13-21(17)29-23-15-16-24(30-22-14-8-4-10-18(22)2)26-25(23)27(31)19-11-5-6-12-20(19)28(26)32/h3-16,29-30H,1-2H3
SMILES:Cc1ccccc1Nc1ccc(Nc2ccccc2C)c2c1C(=O)c1ccccc1C2=O
Molecular Weight: 418.494 g/mole
Molecular Formula: C28H22N2O2

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

not specified

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

not specified

Doses:

2953 mg/kg bw

No. of animals per sex per dose:

10

Control animals:

not specified

Details on study design:

not specified

Statistics:

not specified

Preliminary study:

not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 953 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 50% mortality was observed

Mortality:

not specified

Clinical signs:

other: not specified

Gross pathology:

not specified

Other findings:

not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

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

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as AN2 AND AN2 >>  Michael-type addition, quinoid structures AND AN2 >>  Michael-type addition, quinoid structures >> Quinones and Trihydroxybenzenes AND Non-covalent interaction AND Non-covalent interaction >> DNA intercalation AND Non-covalent interaction >> DNA intercalation >> Quinones and Trihydroxybenzenes AND Radical AND Radical >> Radical mechanism via ROS formation (indirect) AND Radical >> Radical mechanism via ROS formation (indirect) >> Quinones and Trihydroxybenzenes by DNA binding by OASIS v.1.4

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 AN2 AND AN2 >>  Michael-type addition, quinoid structures AND AN2 >>  Michael-type addition, quinoid structures >> Quinones and Trihydroxybenzenes AND Non-covalent interaction AND Non-covalent interaction >> DNA intercalation AND Non-covalent interaction >> DNA intercalation >> Quinones and Trihydroxybenzenes AND Radical AND Radical >> Radical mechanism via ROS formation (indirect) AND Radical >> Radical mechanism via ROS formation (indirect) >> Quinones and Trihydroxybenzenes by DNA binding by OASIS v.1.4

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as AN2 >>  Michael-type addition, quinoid structures >> Flavonoids OR AN2 >>  Michael-type addition, quinoid structures >> Quinoneimines OR AN2 >> Carbamoylation after isocyanate formation OR AN2 >> Carbamoylation after isocyanate formation >> N-Hydroxylamines OR AN2 >> Nucleophilic addition reaction with cycloisomerization OR AN2 >> Nucleophilic addition reaction with cycloisomerization >> Hydrazine Derivatives OR AN2 >> Schiff base formation OR AN2 >> Schiff base formation >> Polarized Haloalkene Derivatives OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation >> Geminal Polyhaloalkane Derivatives OR AN2 >> Shiff base formation after aldehyde release OR AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Haloalkenes with Electron-Withdrawing Groups OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Polarized Haloalkene Derivatives OR No alert found OR Non-covalent interaction >> DNA intercalation >> Acridone, Thioxanthone, Xanthone and Phenazine Derivatives OR Non-covalent interaction >> DNA intercalation >> Amino Anthraquinones OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide and Aminoalkylamine Side Chain OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Nitroaromatics OR Non-specific OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    >> Specific Imine and Thione Derivatives OR Radical >> Generation of ROS by glutathione depletion (indirect) OR Radical >> Generation of ROS by glutathione depletion (indirect) >> Haloalkanes Containing Heteroatom OR Radical >> Radical mechanism via ROS formation (indirect) >> Acridone, Thioxanthone, Xanthone and Phenazine Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Amino Anthraquinones OR Radical >> Radical mechanism via ROS formation (indirect) >> C-Nitroso Compounds OR Radical >> Radical mechanism via ROS formation (indirect) >> Flavonoids OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Nitroaromatics OR Radical >> Radical mechanism via ROS formation (indirect) >> Geminal Polyhaloalkane Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Hydrazine Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> N-Hydroxylamines OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroaniline Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroarenes with Other Active Groups OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids OR Radical >> Radical mechanism via ROS formation (indirect) >> Polynitroarenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Specific Imine and Thione Derivatives OR Radical >> ROS formation after GSH depletion (indirect) OR Radical >> ROS formation after GSH depletion (indirect) >> Haloalcohols OR Radical >> ROS formation after GSH depletion (indirect) >> Quinoneimines OR SN1 OR SN1 >> Carbenium ion formation OR SN1 >> Carbenium ion formation >> Alpha-Haloethers OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> Acyclic Triazenes OR SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Amino Anthraquinones OR SN1 >> Nucleophilic attack after nitrenium ion formation OR SN1 >> Nucleophilic attack after nitrenium ion formation >> N-Hydroxylamines OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Fused-Ring Nitroaromatics OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroaniline Derivatives OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Polynitroarenes OR SN1 >> Nucleophilic substitution after glutathione-induced nitrenium ion formation OR SN1 >> Nucleophilic substitution after glutathione-induced nitrenium ion formation >> C-Nitroso Compounds OR SN1 >> Nucleophilic substitution on diazonium ion OR SN1 >> Nucleophilic substitution on diazonium ion >> Specific Imine and Thione Derivatives OR SN2 OR SN2 >> Acylation OR SN2 >> Acylation >> N-Hydroxylamines OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Acylation involving a leaving group after metabolic activation OR SN2 >> Acylation involving a leaving group after metabolic activation >> Geminal Polyhaloalkane Derivatives OR SN2 >> Alkylation by epoxide metabolically formed after E2 reaction OR SN2 >> Alkylation by epoxide metabolically formed after E2 reaction >> Haloalcohols OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> Alkylation, direct acting epoxides and related after cyclization OR SN2 >> Alkylation, direct acting epoxides and related after cyclization >> Nitrogen and Sulfur Mustards OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Haloalkenes with Electron-Withdrawing Groups OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Polarized Haloalkene Derivatives OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Direct acting epoxides formed after metabolic activation OR SN2 >> Direct acting epoxides formed after metabolic activation >> Quinoline Derivatives OR SN2 >> Direct nucleophilic attack on diazonium cation OR SN2 >> Direct nucleophilic attack on diazonium cation >> Hydrazine Derivatives OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation >> Geminal Polyhaloalkane Derivatives OR SN2 >> SN2 at an activated carbon atom OR SN2 >> SN2 at an activated carbon atom >> Quinoline Derivatives OR SN2 >> SN2 at sp3 and activated sp2 carbon atom OR SN2 >> SN2 at sp3 and activated sp2 carbon atom >> Polarized Haloalkene Derivatives OR SN2 >> SN2 at sp3-carbon atom OR SN2 >> SN2 at sp3-carbon atom >> Alpha-Haloethers OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 >> Nitroarenes with Other Active Groups by DNA binding by OASIS v.1.4

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OECD

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Michael addition OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Alkyl phenols OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Arenes OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Hydroquinones OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Methylenedioxyphenyl OR Michael addition >> Polarised Alkenes-Michael addition OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated amides OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated ketones OR Michael addition >> Quinones and Quinone-type Chemicals OR Michael addition >> Quinones and Quinone-type Chemicals >> Quinones OR SN1 OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion Formation >> Aliphatic tertiary amines OR SN1 >> Nitrenium Ion formation OR SN1 >> Nitrenium Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Secondary aromatic amine by DNA binding by OECD

Domain logical expression index: "g"

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

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Non binder, impaired OH or NH2 group OR Non binder, MW>500 OR Strong binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules (GSH) by Protein binding potency

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Extremely reactive (GSH) OR Extremely reactive (GSH) >> Benzoquinones (MA) by Protein binding potency

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Not bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of log Kow which is >= 5.73

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of log Kow which is <= 10.9

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 2953 mg/kg bw, when 10 male and female Fischer 344 rats were treated with 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) via oral gavage route.

Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4). The LD50 was estimated to be 2953 mg/kg bw, when 10 male and female Fischer 344 rats were treated with 1,4-bis[(2-methylphenyl)amino]anthraquinone via oral gavage route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 953 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from QSAR toolbox 3.4.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Quality of whole database:

Waiver

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

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 predicted using OECD QSAR toolbox version 3.4 and the supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: estimated data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.4

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Specific details on test material used for the study:

Name: 1,4-bis[(2-methylphenyl)amino]anthraquinone
1S/C28H22N2O2/c1-17-9-3-7-13-21(17)29-23-15-16-24(30-22-14-8-4-10-18(22)2)26-25(23)27(31)19-11-5-6-12-20(19)28(26)32/h3-16,29-30H,1-2H3
SMILES:Cc1ccccc1Nc1ccc(Nc2ccccc2C)c2c1C(=O)c1ccccc1C2=O
Molecular Weight: 418.494 g/mole
Molecular Formula: C28H22N2O2

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

not specified

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

not specified

Duration of exposure:

24 hours

Doses:

5857 mg/kg bw

No. of animals per sex per dose:

not specified

Control animals:

not specified

Details on study design:

not specified

Statistics:

not specified

Preliminary study:

not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

5 857 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 50% mortality was observed.

Mortality:

not specified

Clinical signs:

other: not specified

Gross pathology:

not specified

Other findings:

not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 7 nearest neighbours
Domain  logical expression:Result: In Domain

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

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as AN2 AND AN2 >>  Michael-type addition, quinoid structures AND AN2 >>  Michael-type addition, quinoid structures >> Quinones and Trihydroxybenzenes AND Non-covalent interaction AND Non-covalent interaction >> DNA intercalation AND Non-covalent interaction >> DNA intercalation >> Quinones and Trihydroxybenzenes AND Radical AND Radical >> Radical mechanism via ROS formation (indirect) AND Radical >> Radical mechanism via ROS formation (indirect) >> Quinones and Trihydroxybenzenes by DNA binding by OASIS v.1.4

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 Non binder, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "d"

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

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as (!Undefined)Group All Lipid Solubility < 0.01 g/kg AND (!Undefined)Group CN Lipid Solubility < 0.4 g/kg AND Group All Melting Point > 200 C AND Group CN Aqueous Solubility < 0.0001 g/L AND Group CN Aqueous Solubility < 0.1 g/L AND Group CN log Kow > 4.5 AND Group CN log Kow > 5.5 AND Group CN Melting Point > 180 C AND Group CN Molecular Weight > 290 g/mol AND Group CN Vapour Pressure < 0.001 Pa by Skin irritation/corrosion Exclusion rules by BfR

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as (!Undefined)Group C Surface Tension > 62 mN/m by Skin irritation/corrosion Exclusion rules by BfR

Domain logical expression index: "g"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 219 Da

Domain logical expression index: "h"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 596 Da

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 5857 mg/kg bw, when male and female New Zealand White rabbits were treated with 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) for 24 hours by dermal application occlusively.

Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for 1,4-bis[(2-methylphenyl)amino] anthraquinone (CAS no: 6737-68-4). The LD50 was estimated to be 5857 mg/kg bw, when male and female New Zealand White rabbits were treated with 1,4-bis[(2-methylphenyl)amino] anthraquinone for 24 hours by dermal application occlusively.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

5 857 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from QSAR toolbox 3.4.

Additional information

Acute oral toxicity:

In different studies, 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats for 1,4-bis[(2-methylphenyl)amino]anthraquinone along with the study available on structurally similar read across substances sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino] toluene-3-sulphonate (CAS No: 4430-18-6) and 1,4-Bis(p-tolylamino)anthraquinone (CAS no: 128-80-3). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4). The LD50 was estimated to be 2953 mg/kg bw, when 10 male and female Fischer 344 rats were treated with 1,4-bis[(2-methylphenyl)amino]anthraquinone via oral gavage route.

The above study is supported by Sustainability Support Services (Europe) AB (study no.18811, 2016) was designed and conducted for the structurally similar read across substance Sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate (CAS No: 4430-18-6) in Sprague Dawley rats. Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Step - I). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality at 24 hours after the dosing. As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Step - II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. No mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - I). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. As no mortality were observed at 24 hours after the dosing, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - II). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups. It was concluded that the acute oral median lethal dose (LD50) of Sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate supplied by Sustainability Support Services (Europe) AB, when administered to Sprague Dawley rats was found to be >2000 mg/kg body weight. Thus by considering the CLP criteria for acute toxicity rating for the chemicals, it infers that Sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate falls into the Category "Not classified”.

This study is further supported by Richard J. Lewis (Sax's Dangerous Properties of Industrial Materials, 12th Edition, 5 Volume Set, 2012) and U.S. National Library of

Medicine (ChemIDplus, 2017), for the structurally similar read across substance 1,4-Bis(p-tolylamino)anthraquinone (CAS no: 128-80-3). Acute oral toxicity study was conducted in rats at the concentration of 3660 mg/kg bw. 50% mortality was observed in treated rats at 3660 mg/kg bw. Therefore, LD50 was considered to be 3660 mg/kg bw, when rats were treated with1,4-Bis(p-tolylamino)anthraquinone (CAS no: 128-80-3) via oral route.

Thus, based on the above studies on 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 1,4-bis[(2-methylphenyl)amino]anthraquinone cannot be classified for acute oral toxicity.

Acute Inhalation toxicity: 

1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) has very low vapour pressure (3.02E-11 Pa at 25°C), so the potential for the generation of inhalable vapours is very low. Also the normal conditions of use of this substance will not result in aerosols, particles or droplets of an inhalable size, so exposure to humans via the inhalatory route will be highly unlikely and therefore this end point was considered for waiver.

Acute Dermal toxicity:

In different studies, 1,4-bis[(2-methylphenyl)amino] anthraquinone (CAS no: 6737-68-4) has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments in rodents, i.e. most commonly in rabbits and rats for 1,4-bis[(2-methylphenyl)amino] anthraquinone along with the study available on the structurally similar read across substance sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate (CAS No: 4430-18-6) and 1-(2-hydroxyethylamino)-4-(methylamino) anthracene-9,10-dione (CAS no: 2475-46-9). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for 1,4-bis[(2-methylphenyl)amino] anthraquinone (CAS no: 6737-68-4). The LD50 was estimated to be 5857 mg/kg bw, when male and female New Zealand White rabbits were treated with 1,4-bis[(2-methylphenyl)amino] anthraquinone for 24 hours by dermal application occlusively.

This study is supported by Sustainability Support Services (Europe) AB (study no.18812, 2016) was designed and conducted for the structurally similar read across substanceSodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl)amino]toluene-3-sulphonate (CAS No: 4430-18-6) in Sprague Dawley rats. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment. It was concluded that the acute dermal median lethal dose (LD50) of Sodium 4-[(9,10-dihydro-4-hydroxy-9,10-dioxo-1-anthryl) amino]toluene-3- sulphonate supplied by Sustainability Support Services (Europe) AB, when administered to male and female Sprague Dawley rats was found to be >2000 mg/kg body weight. Thus by considering the CLP criteria for acute toxicity rating for the chemicals, it infers that Sodium 4-[(9,10-dihydro-4- hydroxy-9,10-dioxo- 1-anthryl)amino]toluene-3-sulphonate does not exhibits acute toxicity by the dermal route. Classification - Not classified.

The above study is further supported by U.S. National Library of Medicine (ChemIDplus, 2017), for the functionally similar read across substance 1-(2-hydroxyethylamino)-4-(methylamino) anthracene-9,10-dione (CAS no: 2475-46-9). Acute Dermal toxicity study was conducted in rabbits at the concentration of 2000 mg/kg bw. No mortality was observed in treated rabbits at 2000 mg/kg bw. Therefore, LD50 was considered to be >2000 mg/kg bw, when rabbits were treated with1-(2-hydroxyethylamino)-4-(methylamino) anthracene-9,10-dione by dermal application to the skin.

Thus, based on the above studies on 1,4-bis[(2-methylphenyl)amino]anthraquinone (CAS no: 6737-68-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 1,4-bis[(2-methylphenyl)amino]anthraquinone cannot be classified for acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies and prediction on 1,4-bis[(2-methylphenyl)amino] anthraquinone (CAS no: 6737-68-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw for acute oral and dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, 1,4-bis[(2-methylphenyl)amino]anthraquinone cannot be classified for acute oral and dermal toxicity. For Acute Inhalation toxicity wavier was added so, not possible to classify.