2-hydroxy-p-toluic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Gene mutation in vitro:

Ames test:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 2-hydroxy-p-toluic acid. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Chromosome aberration study:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, chromosomal aberration was predicted for 2-hydroxy-p-toluic acid. The study assumed the use of Chinese hamster ovary (CHO) cell line with and without S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce chromosomal aberrations in Chinese hamster ovary (CHO) cell line in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

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 the supporting QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

Prediction is done using OECD QSAR Toolbox version 3.3, 2017

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Name of test material : 2-hydroxy-p-toluic acid (m cresotic acid)
- Molecular formula :C8H8O3
- Molecular weight :152.148 g/mol
- Smiles notation :Cc1ccc(c(c1)O)C(=O)O
- InChl :1S/C8H8O3/c1-5-2-3-6(8(10)11)7(9)4-5/h2-4,9H,1H3,(H,10,11)
- Substance Type: Organic
- Physical State: Solid

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Details on mammalian cell type (if applicable):

Not applicable.

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

not specified

Metabolic activation:

with

Metabolic activation system:

S9 metabolic activation

Test concentrations with justification for top dose:

not specified

Vehicle / solvent:

not specified

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Details on test system and experimental conditions:

not specified

Rationale for test conditions:

not specified

Evaluation criteria:

Prediction was done considering a dose dependent increase in the number of revertants/plate.

Statistics:

not specified

Species / strain:

S. typhimurium, other: TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

Not specified

Remarks on result:

other: No mutagenic effect were observed.

The prediction was based on dataset comprised from the following descriptors: "Gene mutation"
Estimation method: Takes highest mode 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 ( not "i") )  )  and ("j" and ( not "k") )  )  and ("l" and ( not "m") )  )  and "n" )  and "o" )  and "p" )  and ("q" and ( not "r") )  )  and ("s" and ( not "t") )  )  and ("u" and ( not "v") )  )  and ("w" and ( not "x") )  )  and ("y" and ( not "z") )  )  and ("aa" and ( not "ab") )  )  and ("ac" and "ad" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as m,p - Cresols by OECD HPV Chemical Categories

Domain logical expression index: "b"

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

Domain logical expression index: "c"

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

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Class 2 (less inert compounds) by Acute aquatic toxicity classification by Verhaar (Modified)

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Acid moiety AND Phenols by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "f"

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

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >>  Michael-type addition, quinoid structures OR AN2 >>  Michael-type addition, quinoid structures >> Flavonoids OR AN2 >>  Michael-type addition, quinoid structures >> Quinoneimines OR AN2 >>  Michael-type addition, quinoid structures >> Quinones OR AN2 >> Carbamoylation after isocyanate formation OR AN2 >> Carbamoylation after isocyanate formation >> Hydroxamic Acids OR AN2 >> Carbamoylation after isocyanate formation >> N-Hydroxylamines OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds >> Four- and Five-Membered Lactones 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 >> Shiff base formation for aldehydes OR AN2 >> Shiff base formation for aldehydes >> Geminal Polyhaloalkane Derivatives OR Non-covalent interaction OR Non-covalent interaction >> DNA intercalation 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 >> Aminoacridine DNA Intercalators OR Non-covalent interaction >> DNA intercalation >> Coumarins OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide Side Chain OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Nitroaromatics OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines OR Non-covalent interaction >> DNA intercalation >> Quinones OR Radical OR Radical >> Generation of reactive oxygen species OR Radical >> Generation of reactive oxygen species >> Thiols 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 by ROS formation OR Radical >> Radical mechanism by ROS formation >> Acridone, Thioxanthone, Xanthone and Phenazine Derivatives OR Radical >> Radical mechanism by ROS formation >> Polynitroarenes OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Amino Anthraquinones OR Radical >> Radical mechanism via ROS formation (indirect) >> Anthrones OR Radical >> Radical mechanism via ROS formation (indirect) >> C-Nitroso Compounds OR Radical >> Radical mechanism via ROS formation (indirect) >> Conjugated Nitro Compounds OR Radical >> Radical mechanism via ROS formation (indirect) >> Coumarins 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) >> Fused-Ring Primary Aromatic Amines OR Radical >> Radical mechanism via ROS formation (indirect) >> Geminal Polyhaloalkane Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Haloalcohols 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) >> Nitro Azoarenes 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) >> p-Aminobiphenyl Analogs OR Radical >> Radical mechanism via ROS formation (indirect) >> p-Substituted Mononitrobenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Quinones OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR Radical >> ROS formation after GSH depletion (indirect) OR Radical >> ROS formation after GSH depletion (indirect) >> Quinoneimines OR SN1 OR SN1 >> Alkylation after metabolically formed carbenium ion species OR SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> N-Nitroso Compounds 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 metabolic nitrenium ion formation >> Fused-Ring Primary Aromatic Amines OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> N-Hydroxylamines OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> p-Aminobiphenyl Analogs OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines OR SN1 >> Nucleophilic attack after nitrenium and/or carbenium ion formation OR SN1 >> Nucleophilic attack after nitrenium and/or carbenium ion formation >> N-Nitroso Compounds OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Conjugated Nitro Compounds OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Fused-Ring Nitroaromatics OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitro Azoarenes 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 >> Nitrobiphenyls and Bridged Nitrobiphenyls 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 attack after reduction and nitrenium ion formation >> p-Substituted Mononitrobenzenes 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 >> SN1 reaction at nitrogen-atom bound to a good leaving group or on  nitrenium ion OR SN1 >> SN1 reaction at nitrogen-atom bound to a good leaving group or on  nitrenium ion >> N-Acyloxy(Alkoxy) Arenamides OR SN2 OR SN2 >> Acylation OR SN2 >> Acylation >> Hydroxamic Acids OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Acylation involving a leaving group  OR SN2 >> Acylation involving a leaving group  >> Geminal Polyhaloalkane Derivatives 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 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 >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Sulfonates and Sulfates OR SN2 >> Alkylation, ring opening SN2 reaction OR SN2 >> Alkylation, ring opening SN2 reaction >> Four- and Five-Membered Lactones OR SN2 >> Direct acting epoxides formed after metabolic activation OR SN2 >> Direct acting epoxides formed after metabolic activation >> Coumarins OR SN2 >> Direct acting epoxides formed after metabolic activation >> Quinoline 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 Nitrogen Atom OR SN2 >> SN2 at Nitrogen Atom >> N-acetoxyamines 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 OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group >> N-Acetoxyamines OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group or nitrenium ion OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group or nitrenium ion >> N-Acyloxy(Alkoxy) Arenamides by DNA binding by OASIS v.1.3

Domain logical expression index: "h"

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

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Michael addition OR Michael addition >> P450 Mediated Activation of Heterocyclic Ring Systems OR Michael addition >> P450 Mediated Activation of Heterocyclic Ring Systems >> Furans OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> 5-alkoxyindoles 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 >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Polycyclic (PAHs) and heterocyclic (HACs) aromatic hydrocarbons-Michael addition 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 >> Carbenium Ion Formation OR SN1 >> Carbenium Ion Formation >> Allyl benzenes OR SN1 >> Carbenium Ion Formation >> Polycyclic (PAHs) and heterocyclic (HACs) aromatic hydrocarbons-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 azo OR SN1 >> Nitrenium Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Aromatic phenylureas OR SN1 >> Nitrenium Ion formation >> Primary (unsaturated) heterocyclic amine OR SN1 >> Nitrenium Ion formation >> Primary aromatic amine OR SN1 >> Nitrenium Ion formation >> Secondary aromatic amine OR SN1 >> Nitrenium Ion formation >> Tertiary aromatic amine OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding by OECD

Domain logical expression index: "j"

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

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Moderate binder, NH2 group OR Moderate binder, OH grooup OR Non binder, impaired OH or NH2 group OR Non binder, MW>500 OR Non binder, non cyclic structure OR Non binder, without OH or NH2 group OR Strong binder, NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "l"

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

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Ester aminolysis OR Acylation >> Ester aminolysis >> Amides OR Schiff base formation OR Schiff base formation >> Schiff base formation with carbonyl compounds OR Schiff base formation >> Schiff base formation with carbonyl compounds >> Aldehydes by Protein binding by OASIS v1.3

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as No superfragment by Superfragments ONLY

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Low (Class I) by Toxic hazard classification by Cramer (original) ONLY

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Low (Class I) by Toxic hazard classification by Cramer (with extensions) ONLY

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Group 14 - Carbon C AND Group 16 - Oxygen O by Chemical elements

Domain logical expression index: "r"

Referential boundary: The target chemical should be classified as Group 15 - Nitrogen N by Chemical elements

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as Phenols by Skin irritation/corrosion Inclusion rules by BfR

Domain logical expression index: "t"

Referential boundary: The target chemical should be classified as Aldehydes OR Inclusion rules not met OR Ketones by Skin irritation/corrosion Inclusion rules by BfR

Domain logical expression index: "u"

Referential boundary: The target chemical should be classified as (!Undefined)Group All Lipid Solubility < 0.01 g/kg AND (!Undefined)Group C Surface Tension > 62 mN/m AND Group C Melting Point > 55 C by Skin irritation/corrosion Exclusion rules by BfR

Domain logical expression index: "v"

Referential boundary: The target chemical should be classified as Group All Melting Point > 200 C OR Group C Vapour Pressure < 0.0001 Pa by Skin irritation/corrosion Exclusion rules by BfR

Domain logical expression index: "w"

Referential boundary: The target chemical should be classified as No alert found by Respiratory sensitisation

Domain logical expression index: "x"

Referential boundary: The target chemical should be classified as Pro-SN2 OR Pro-SN2 >> Pro-ring opening SN2 OR Pro-SN2 >> Pro-ring opening SN2 >> Vinyl benzenes by Respiratory sensitisation

Domain logical expression index: "y"

Referential boundary: The target chemical should be classified as Phenol Type Compounds by Oncologic Primary Classification

Domain logical expression index: "z"

Referential boundary: The target chemical should be classified as Polycyclic Aromatic Hydrocarbons - Homocyclic by Oncologic Primary Classification

Domain logical expression index: "aa"

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 >> Phenols by Protein binding alerts for Chromosomal aberration by OASIS v1.1

Domain logical expression index: "ab"

Referential boundary: The target chemical should be classified as Ac-SN2 OR Ac-SN2 >> Acylation involving an activated (glucuronidated) ester group OR Ac-SN2 >> Acylation involving an activated (glucuronidated) ester group >> Arenecarboxylic Acid Esters OR No alert found by Protein binding alerts for Chromosomal aberration by OASIS v1.1

Domain logical expression index: "ac"

Parametric boundary:The target chemical should have a value of log Kow which is >= 2.55

Domain logical expression index: "ad"

Parametric boundary:The target chemical should have a value of log Kow which is <= 3.52

Conclusions:

2-hydroxy-p-toluic acid (50-85-1) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

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 five closest read across substances, gene mutation was predicted for 2-hydroxy-p-toluic acid (50-85-1). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

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 the supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

Prediction is done using OECD QSAR Toolbox version 3.3, 2018

GLP compliance:

not specified

Type of assay:

in vitro mammalian chromosome aberration test

Specific details on test material used for the study:

- Name of test material : 2-hydroxy-p-toluic acid (m cresotic acid)
- Molecular formula :C8H8O3
- Molecular weight :152.148 g/mol
- Smiles notation :Cc1ccc(c(c1)O)C(=O)O
- InChl :1S/C8H8O3/c1-5-2-3-6(8(10)11)7(9)4-5/h2-4,9H,1H3,(H,10,11)
- Substance Type: Organic
- Physical State: Solid

Target gene:

No data

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Details on mammalian cell type (if applicable):

No data

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with and without

Metabolic activation system:

S9 metabolic activation system

Test concentrations with justification for top dose:

No data

Vehicle / solvent:

No data

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Positive control substance:

not specified

Details on test system and experimental conditions:

No data

Rationale for test conditions:

No data

Evaluation criteria:

The cell line was observed for chromosome aberrations

Statistics:

No data

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

No data

Remarks on result:

no mutagenic potential (based on QSAR/QSPR prediction)

The prediction was based on dataset comprised from the following descriptors: "chromosome aberration"
Estimation method: Takes highest mode value from the 6 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 ( not "i") )  )  and ("j" and ( not "k") )  )  and ("l" and ( not "m") )  )  and ("n" and ( not "o") )  )  and ("p" and "q" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as m,p - Cresols by OECD HPV Chemical Categories

Domain logical expression index: "b"

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

Domain logical expression index: "c"

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

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acid moiety AND Phenols by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Class 2 (less inert compounds) by Acute aquatic toxicity classification by Verhaar (Modified)

Domain logical expression index: "f"

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

Domain logical expression index: "g"

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 Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines OR 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) >> Fused-Ring Primary Aromatic Amines 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) >> p-Substituted Mononitrobenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR SN1 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 >> Fused-Ring Primary Aromatic Amines 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 >> 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 attack after reduction and nitrenium ion formation >> p-Substituted Mononitrobenzenes OR SN2 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.1.3

Domain logical expression index: "h"

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

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Moderate binder, NH2 group OR Moderate binder, OH grooup OR Non binder, impaired OH or NH2 group OR Non binder, MW>500 OR Non binder, non cyclic structure OR Non binder, without OH or NH2 group OR Strong binder, NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "j"

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

Domain logical expression index: "k"

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 >> Hydroquinones OR SN1 OR SN1 >> Carbenium Ion Formation OR SN1 >> Carbenium Ion Formation >> Allyl benzenes by DNA binding by OECD

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Non-Metals by Groups of elements

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Halogens by Groups of elements

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Methyldopa (Hepatotoxicity) Alert by Repeated dose (HESS)

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Phenols (Mucous membrane irritation) Rank C by Repeated dose (HESS)

Domain logical expression index: "p"

Parametric boundary:The target chemical should have a value of log Kow which is >= 2

Domain logical expression index: "q"

Parametric boundary:The target chemical should have a value of log Kow which is <= 3.42

Conclusions:

2-hydroxy-p-toluic acid was predicted to not induce chromosomal aberrations in Chinese hamster ovary (CHO) cell line in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

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 five closest read across substances, chromosomal aberration was predicted for 2-hydroxy-p-toluic acid. The study assumed the use of Chinese hamster ovary (CHO) cell line with and without S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce chromosomal aberrations in Chinese hamster ovary (CHO) cell line in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Gene mutation in vitro:

Prediction model based estimatioin and data from read across chemicals has been reviewed to determine the mutagenic nature of 2-hydroxy-p-toluic acid

The studies are as mentioned below:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 2-hydroxy-p-toluic acid (CAS no 50-85-1). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, chromosomal aberration was predicted for 2-hydroxy-p-toluic acid. The study assumed the use of Chinese hamster ovary (CHO) cell line with and without S9 metabolic activation system. 2-hydroxy-p-toluic acid was predicted to not induce chromosomal aberrations in Chinese hamster ovary (CHO) cell line in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Gene mutation toxicity was predicted for m 2-hydroxy-p-toluic acid (50-85-1) using the battery approach from Danish QSAR database (2017). The study assumed the use of Salmonella typhimurium bacteria in the Ames test. The end point for gene mutation has been modeled in the Danish QSAR using the three software systems Leadscope, CASE Ultra and SciQSAR. Based on predictions from these three systems, a fourth and overall battery prediction is made. The battery prediction is made using the so called Battery algorithm. With the battery approach it is in many cases possible to reduce “noise” from the individual model estimates and thereby improve accuracy and/or broaden the applicability domain.   2-hydroxy-p-toluic acid was assumed not induce mutation in Salmonella typhimurium by the Ames assay performed and hence the chemical 2-hydroxy-p-toluic acid predicted not classify as a gene mutant in vitro.

The predicted data id further supported by the data from read across chemicals as mentioned below:

An in vitro mammalian cell gene mutation study was designed and conducted (Sustainability SUpport Services (Europe) AB, 2015) to determine the genotoxicity profile of read across chemical Sodium salicylate (RA CAS No. 54-21-7) when administered to Chinese Hamster Ovary (CHO) cells. In the genotoxicity test, sodium salicylate was administered to CHO cells for 3 hrs at the dose levels of 0.0625, 0.125, 0.25 or 0.5 mM and in the absence or presence of exogenous metabolic activation. CHO cells representing the negative controls were exposed to the vehicle. Positive controls, such as N-ethyl-N-nitrosourea (ENU) experiments without metabolic activation and 7, 12 dimethylbenz (a) anthracene in experiments with metabolic activation, were also included in each test. Only the positive control ENU gave a clear indication of gene mutations occurring while no other treatment gave rise to gene toxicity. Two very diffuse colonies were seen in one well out of four at the concentration 0.0625 mM and in the presence with 4% S9 liver microsomal fraction. These diffuse colonies are not regarded to be relevant since the two spots were only mildly colored by crystal violet, thus indicating that it was a small cluster of apoptotic cells taking their last breath instead of cells surviving the TG-selection. This is further supported by the results of the higher tested concentrations of sodium salicylate, i.e. these concentrations did not show any evidence of diffuse or clear colonies present. When the mutation frequency was determined, a frequency of 3.08 x 10-4was shown after a 3 hour exposure of ENU as the positive control and in the absence of S9 liver microsomal fraction. Since no other tested concentration of sodium salicylate in the absence or presence of S9 liver microsomal fraction resulted in colonies, we conclude that sodium salicylate does not give rise to gene mutations when CHO cells are exposed in vitro to the test chemical at 0, 0.0625, 0.125, 0.25 or 0.5 mM for 3 hrs. Based on the results of the current study, we conclude that sodium salicylate does not give rise to gene mutations when CHO cells are exposed to the test chemical in vitro at 0, 0.0625, 0.125, 0.25 or 0.5 mM for 3 hrs, in the presence or absence of metabolic activation. Therefore Sodium salicylate was considered to be non mutagenic and hence cannot be classified as gene mutant in vitro.

   

Similarly another RA chemical which support classification is for the read across chemical (RA CAS no 69-72-7) salicylic acid conducted by Joyce Mccannet al.  (Proc. Nat. Acad. Sci. USA). In vitro detection of gene toxicity of salicylic acid as mutagens in the Salmonella/microsome test. Test was performed by using plate incorporation method with the maximum concentration of 500 µg. The chemical consider positive if the number of revertants per plate and nmol was higher than the standard concentration. Salicylic acid show less revertant i.e. < 0.02 revertant per nmol and thus it was consider as nonmutagenic. < 0.02 his revertants obtain when Salmonella typhimurium strain TA100, TA1535, TA1537, and TA98 exposed with the 500 µg of salicylic acid. In the absence and presence of the S-9 fraction (9000 x g supernatat of rat liver) induced with Aroclor 1254, negative result obtain and indicate nonmutagenic nature of salicylic acid.

Gene mutation toxicity study was also performed by Florin et al (Toxicology, 1980) to determine the mutagenic nature of the test compound benzyl benzoate. The material was dissolved in ethanol and applied at a concentration of 3 µmole/plate in the spot test performed to Salmonella typhimurium LT-2 strains TA 98, TA 100, TA 1535, and TA 1537 with and without S9 metabolic activation system. Concurrent positive control chemicals were also included in the study. Benzyl benzoate did not induce reversion of mutant strains and hence is not mutagenic in the bacterium Salmonella typhimurium LT-2 strains TA 98, TA 100, TA 1535, and TA 1537 with and without S9 metabolic activation system and hence the chemical is not likely to classify as gene mutant in vitro.

In another study by Zeiger et al (Environmental Mutagenesis, 1987), Salmonella/microsome test in the absence of exogenous metabolic activation and in the presence of liver S-9 from Aroclor-induced male Sprague-Dawley rats and Syrian hamsters was performed to evaluate the mutagenic nature of the read across chemical Benzyl salicylate (RA CAS no 118 -58 -1). The test compound was dissolved in DMSO and used at a dosage level of 0, 0.3, 1, 3.3, 10, 20, 33, 100, 333 and 666 µg/plate in Lab 1 and 0, 3.3, 10, 33, 100, 333 µg/plate in Lab 2 in the preincubation assay of 48 hrs. Concurrent solvent and negative control chemicals were also included in the study. Benzyl salicylate did not induce gene mutation in the S. typhimurium tester strains TA 1535, TA 1537, TA 98 and TA 100 in the presence and absence of S9 metabolic activation system and and hence it is negative for mutation in vitro.

 

Based on the data available for the target chemical its read across, 2 -hydroxy-p-toluic acid does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant in vitro as per the criteria mentioned in CLP regulation.

Justification for classification or non-classification

Based on the data available for the target chemical its read across, 2 -hydroxy-p-toluic acid (CAS no 50 -85 -1) does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant in vitro as per the criteria mentioned in CLP regulation.