5-acetamido-2-aminobenzenesulphonic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

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-amino-5-acetamidobenzene-1-sulfonic 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-amino-5-acetamidobenzene-1-sulfonic 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.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

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 3.4 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 3.4, 2017

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Name of the test material: 2-amino-5-acetamidobenzene-1-sulfonic acid
- IUPAC name: 2-amino-5-acetamidobenzene-1-sulfonic acid
- Molecular formula: C8H10N2O4S
- Molecular weight: 230.243 g/mol
- Substance type: Organic
- Smiles: O=C(Nc1ccc(N)c(S(=O)(=O)O)c1)C

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):

No data

Metabolic activation:

with

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:

Prediction is done considering a dose dependent increase in the number of rertants/plate

Statistics:

No data

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:

No data

Remarks on result:

no mutagenic potential (based on QSAR/QSPR prediction)

The prediction was based on dataset comprised from the following descriptors: "Gene mutation"
Estimation method: Takes highest mode value from the 7 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" )  and ("r" and "s" )  )

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 nitrenium ion formation AND SN1 >> Nucleophilic attack after nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines by DNA binding by OASIS v.1.4

Domain logical expression index: "c"

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

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Acylation involving an activated (glucuronidated) carboxamide group AND Acylation >> Acylation involving an activated (glucuronidated) carboxamide group >> Carboxylic Acid Amides AND Acylation >> Direct acylation involving a leaving group AND Acylation >> Direct acylation involving a leaving group >> Carboxylic Acid Amides AND Acylation >> Ester aminolysis AND Acylation >> Ester aminolysis >> Amides AND AN2 AND AN2 >> Michael-type addition to quinoid structures  AND AN2 >> Michael-type addition to quinoid structures  >> Carboxylic Acid Amides AND AN2 >> Michael-type addition to quinoid structures  >> Substituted Anilines by Protein binding by OASIS v1.4

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Direct Acylation Involving a Leaving group AND Acylation >> Direct Acylation Involving a Leaving group >> Acetates by Protein binding by OECD

Domain logical expression index: "f"

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 nitrenium ion formation AND SN1 >> Nucleophilic attack after nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines by DNA binding by OASIS v.1.4

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 >> Quinone methides OR AN2 >>  Michael-type addition, quinoid structures >> Quinoneimines OR AN2 >>  Michael-type addition, quinoid structures >> Quinones and Trihydroxybenzenes OR AN2 >> Carbamoylation after isocyanate formation 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 >> Michael-type conjugate addition to activated alkene derivatives OR AN2 >> Michael-type conjugate addition to activated alkene derivatives >> Alpha-Beta Conjugated Alkene Derivatives with Geminal Electron-Withdrawing Groups 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 >> Dicarbonyl compounds OR AN2 >> Schiff base formation >> Halofuranones OR AN2 >> Schiff base formation >> Specific 5-Substituted Uracil 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 No alert found 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 and Aminoalkylamine 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 >> Organic Azides OR Non-covalent interaction >> DNA intercalation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR Non-covalent interaction >> DNA intercalation >> Quinones and Trihydroxybenzenes OR Non-covalent interaction >> DNA intercalation >> Specific 5-Substituted Uracil Derivatives 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 by ROS formation OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA >> Organic Peroxy Compounds OR Radical >> Radical mechanism by ROS formation >> Five-Membered Aromatic Nitroheterocycles OR Radical >> Radical mechanism by ROS formation >> Organic Azides 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) >> 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) >> 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) >> Nitrobiphenyls and Bridged Nitrobiphenyls 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) >> Polynitroarenes OR Radical >> Radical mechanism via ROS formation (indirect) >> p-Substituted Mononitrobenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Quinones and Trihydroxybenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Specific Imine and Thione Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Thiols OR Radical >> ROS formation after GSH depletion OR Radical >> ROS formation after GSH depletion (indirect) OR Radical >> ROS formation after GSH depletion (indirect) >> Quinoneimines OR Radical >> ROS formation after GSH depletion >> Quinone methides OR SN1 >> Alkylation after metabolically formed carbenium ion species OR SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR SN1 >> Alkylation by carbenium ion formed OR SN1 >> Alkylation by carbenium ion formed >> Diazoalkanes 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 >> Pyrrolizidine Derivatives 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 nitrene formation OR SN1 >> Nucleophilic attack after nitrene formation >> Organic Azides OR SN1 >> Nucleophilic attack after nitrenium ion formation >> N-Hydroxylamines OR SN1 >> Nucleophilic attack after nitrenium ion formation >> p-Aminobiphenyl Analogs OR SN1 >> Nucleophilic attack after nitrosonium cation formation OR SN1 >> Nucleophilic attack after nitrosonium cation 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 >> Nucleophilic substitution on diazonium ion OR SN1 >> Nucleophilic substitution on diazonium ion >> Specific Imine and Thione Derivatives 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-Aryl-N-Acetoxy(Benzoyloxy) Acetamides 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 OR SN2 >> Alkylation >> Alkylphosphates, Alkylthiophosphates and Alkylphosphonates 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 >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Specific 5-Substituted Uracil Derivatives 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 >> Direct nucleophilic attack on diazonium cation OR SN2 >> Direct nucleophilic attack on diazonium cation >> Hydrazine Derivatives OR SN2 >> DNA alkylation OR SN2 >> DNA alkylation >> Vicinal Dihaloalkanes OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) >> Vicinal Dihaloalkanes 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 >> Halofuranones 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 sulfur atom OR SN2 >> SN2 at sulfur atom >> Sulfonyl Halides 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-Aryl-N-Acetoxy(Benzoyloxy) Acetamides by DNA binding by OASIS v.1.4

Domain logical expression index: "h"

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: "i"

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

Domain logical expression index: "j"

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

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as No alert found by DNA alerts for AMES by OASIS v.1.4

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR SN1 OR SN1 >> Nucleophilic attack after nitrenium ion formation OR SN1 >> Nucleophilic attack after nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines by DNA alerts for AMES by OASIS v.1.4

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as No alert found by DNA alerts for CA and MNT by OASIS v.1.1

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR SN1 OR SN1 >> Nucleophilic attack after nitrenium ion formation OR SN1 >> Nucleophilic attack after nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines by DNA alerts for CA and MNT by OASIS v.1.1

Domain logical expression index: "p"

Similarity boundary:Target: CC(=O)Nc1ccc(N)c(S(O)(=O)=O)c1
Threshold=40%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is >= -5.34

Domain logical expression index: "s"

Parametric boundary:The target chemical should have a value of log Kow which is <= -0.595

Conclusions:

2-amino-5-acetamidobenzene-1-sulfonic 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.

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-amino-5-acetamidobenzene-1-sulfonic 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-amino-5-acetamidobenzene-1-sulfonic 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.

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 estimation for the target chemical and data from read across chemicals have been reviewed to determine the mutagenic nature of 2-amino-5-acetamidobenzene-1-sulfonic acid. The studies is 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-amino-5-acetamidobenzene-1-sulfonic acid. 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-amino-5-acetamidobenzene-1-sulfonic 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.

Gene mutation toxicity was predicted for 2-amino-5-acetamidobenzene-1-sulfonic acid 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. Gene mutation toxicity study as predicted by Danish QSAR for 2-amino-5-acetamidobenzene-1-sulfonic acid is negative and hence the chemical is predicted to not classify as a gene mutant in vitro.

In a study for 60 -70% structurally similar read across chemical by Zeiger et al (Environmental and Molecular Mutagenesis, 1988), m-Amino benzenesulfonic acid (RA CAS no 121 -47 -1; IUPAC name: m-Amino benzenesulfonic acid) was studied for its ability to induce mutations in strains of Salmonella typhimurium. The test compound was dissolved in DMSO and was tested at concentration of 0, 33, 100, 333, 1000 or 3333 µg/plate using Salmonella typhimurium TA100, TA1535, TA97 and TA98 in the presence and absence of 10 % and 30 % rat and hamster liver S9 metabolic activation system. Preincubation assay was performed with a preicubation for 20 mins. The plates were observed for histidine independence after 2 days incubation period. Concurrent solvent and positive controls were included in the study.  m-Amino benzene sulfonic acidis not mutagenic to theSalmonella typhimurium TA100, TA1535, TA97 and TA98 in the presence and absence of rat and hamster liver S9 metabolic activation system and hence it is not likely to classify as a gene mutant in vitro.

In another study performed by Zeiger et al (Environmental and Molecular Mutagenesis, 1992) gene mutation toxicity study was performed to determine the mutagenic nature of 50 -60% structurally similar read across chemical N-Acetyl-p-toluidine (RA CAS no 103 -89 -9; IUPAC name: 4'-Methylacetanilide). The study was performed using Salmonella typhimurium strains TA98, TA97, TA100 and TA1535 in the presence and absence of S9 metabolic activation system. The chemical was dissolved in DMSO as solvent and used at dose levels 0, 100, 333, 1000, 3333, 6666, 6667 or 10000 µg/plate by the preincubation method. The doses were selected on the basis of preliminary dose range finding study and concurrent solvent and positive controls were included in the study. N-Acetyl-p-toluidine did not induce gene mutation in Salmonella typhimurium TA98, TA100, TA1538 in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Garner and Nutman (Mutation research, 1977) performed gene toxicity in vitro study on theSalmonella typhimurium TA1538 strain for 60 -70% structurally simlar read across chemical 4-Amino-1-naphthalene sulphonic acid (RA CAS no 84 -86 -6; IUPAC name: Naphthionic acid). 4-Amino-1-naphthalene sulphonic acid was dissolved in DMSO and used at a concentration of 0, 50 and 100 µg/ plate in the presence and absence of S9 metabolic activation system. The plates were incubated for 48 hrs. Concurrent solvent and positive control chemicals were included in the study. All assays were performed in duplicate and the numbers of revertants on test plates greater than 30 was classified as being significantly mutagenic. 4-Amino-1-naphthalene sulphonic acid failed to induce mutation in Salmonella typhimurium TA1538 strain with and without S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Based on the data available for the target chemical and its read across, 2-amino-5-acetamidobenzene-1-sulfonic 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 and its read across, 2-amino-5-acetamidobenzene-1-sulfonic acid (CAS no 96 -78 -6) 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.