m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

Data is from OECD QSAR toolbox version.3.3 and QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: Predicted data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3 with log kow as the primary discriptors.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid
- IUPAC name: 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid
- Molecular formula: C10H11N3O3S
- Molecular weight: 253.281 g/mole
- Smiles: O=S(=O)(O)c1cccc(N2N=C(CC2=N)C)c1
- Inchl: 1S/C10H11N3O3S/c1-7-5-10(11)13(12-7)8-3-2-4-9(6-8)17(14,15)16/h2-4,6,11H,5H2,1H3,(H,14,15,16)
- Substance type: Organic
- Physical state: Solid

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

179.348 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: not toxic

The prediction was based on dataset comprised from the following descriptors: EC50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((((((((((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and ("m" and ( not "n") )  )  and ("o" and ( not "p") )  )  and "q" )  and ("r" and ( not "s") )  )  and ("t" and ( not "u") )  )  and ("v" and ( not "w") )  )  and ("x" and ( not "y") )  )  and "z" )  and ("aa" and ( not "ab") )  )  and ("ac" and ( not "ad") )  )  and ("ae" and "af" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Aromatic compound OR Heterocyclic compound OR Sulfonic acid OR Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aliphatic Nitrogen, one aromatic attach [-N] OR Aromatic Carbon [C] OR Azomethine, aliphatic attach [-N=C] OR Hydrazine [>N-N<] OR Hydroxy, sulfur attach [-OH] OR Miscellaneous sulfide (=S) or oxide (=O) OR Nitrogen, two or tree olefinic attach [>N-] OR Olefinic carbon [=CH- or =C<] OR Suflur {v+4} or {v+6} OR Sulfinic acid [-S(=O)OH] OR Sulfonate, aromatic attach [-SO2-O] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Amidine OR Aryl OR Overlapping groups OR Sulfonic acid OR Unsaturated heterocyclic amine OR Unsaturated heterocyclic fragment by Organic Functional groups (nested) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Amidine OR Aryl OR Sulfonic acid OR Unsaturated heterocyclic amine OR Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "e"

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

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines OR Non-covalent interaction >> DNA intercalation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Primary Aromatic Amines OR SN1 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 >> Nucleophilic attack after metabolic nitrenium ion formation OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Fused-Ring Primary Aromatic Amines OR SN2 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 by DNA binding by OASIS v.1.4

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No alert found by Protein binding by OASIS v1.4

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Michael-type addition to activated double bonds in vinyl pyridines OR AN2 >> Michael-type addition to activated double bonds in vinyl pyridines >> Ethenyl Pyridines OR AN2 >> Nucleophilic addition to pyridonimine tautomer of aminopyridoindoles or aminopyridoimidazoles (hypothesized) OR AN2 >> Nucleophilic addition to pyridonimine tautomer of aminopyridoindoles or aminopyridoimidazoles (hypothesized) >> Heterocyclic Aromatic Amines OR Michael addition OR Michael addition >> Michael addition on polarised Alkenes OR Michael addition >> Michael addition on polarised Alkenes >> Polarised Alkene - alkenyl pyridines, pyrazines, pyrimidines or triazines  OR Radical reactions OR Radical reactions >> ROS generation and direct attack of hydroxyl radical to the C8 position of nucleoside base OR Radical reactions >> ROS generation and direct attack of hydroxyl radical to the C8 position of nucleoside base >> Heterocyclic Aromatic Amines OR SE reaction (CYP450-activated heterocyclic amines) OR SE reaction (CYP450-activated heterocyclic amines) >> Direct attack of arylnitrenium cation to the C8 position of nucleoside base  OR SE reaction (CYP450-activated heterocyclic amines) >> Direct attack of arylnitrenium cation to the C8 position of nucleoside base  >> Heterocyclic Aromatic Amines OR SR reaction (peroxidase-activated heterocyclic amines) OR SR reaction (peroxidase-activated heterocyclic amines) >> Direct attack of arylnitrenium radical to the C8 position of nucleoside base OR SR reaction (peroxidase-activated heterocyclic amines) >> Direct attack of arylnitrenium radical to the C8 position of nucleoside base >> Heterocyclic Aromatic Amines by Protein binding by OASIS v1.4

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Not Related to an Existing ECOSAR Class by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Aliphatic Amines OR Alkoxy Silanes by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Not Related to an Existing ECOSAR Class by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Anilines (amino-meta) OR Imidazoles by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Not Related to an Existing ECOSAR Class by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Inorganic Compound by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Not Related to an Existing ECOSAR Class by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Thiols and Mercaptans OR Thiophenes OR Vinyl/Allyl Ethers by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "q"

Similarity boundary:Target: CC1CC(=N)N(c2cccc(S(O)(=O)=O)c2)N=1
Threshold=30%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "r"

Referential boundary: The target chemical should be classified as Aromatic compound AND Heterocyclic compound AND Sulfonic acid AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as Carbonic acid derivative by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "t"

Referential boundary: The target chemical should be classified as Amidine AND Aryl AND Overlapping groups AND Sulfonic acid AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups (nested)

Domain logical expression index: "u"

Referential boundary: The target chemical should be classified as Surfactants - Anionic OR Terpenes by Organic Functional groups (nested)

Domain logical expression index: "v"

Referential boundary: The target chemical should be classified as Amidine AND Aryl AND Overlapping groups AND Sulfonic acid AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups (nested)

Domain logical expression index: "w"

Referential boundary: The target chemical should be classified as Phosphite ester by Organic Functional groups (nested)

Domain logical expression index: "x"

Referential boundary: The target chemical should be classified as Amidine AND Aryl AND Sulfonic acid AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups

Domain logical expression index: "y"

Referential boundary: The target chemical should be classified as Alkene by Organic Functional groups

Domain logical expression index: "z"

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

Domain logical expression index: "aa"

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

Domain logical expression index: "ab"

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

Domain logical expression index: "ac"

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

Domain logical expression index: "ad"

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

Domain logical expression index: "ae"

Parametric boundary:The target chemical should have a value of log Kow which is >= -4.34

Domain logical expression index: "af"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.785

Conclusions:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the closest read across substances, the toxicity to aquatic algae was predicted 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5). EC50 growth rate value was estimated to be 179.348 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5) was likely to be not toxic to aquatic algae.

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 closest read across substances, the toxicity to aquatic algae was predicted 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5). EC50 growth rate value was estimated to be 179.348 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5) was likely to be not toxic to aquatic algae.

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 closest read across substances, the toxicity to aquatic algae was predicted 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5). EC50 growth rate value was estimated to be 179.348 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5) was likely to be not toxic to aquatic algae.

Key value for chemical safety assessment

EC50 for freshwater algae:

179.348 mg/L

Additional information

Following studies of target chemical and structurally similar read across includes predicted data and experimental data to conclude the toxicity extent of m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS no. 68083 -38 -5) towards algae is summarized as follows:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the closest read across substances, the toxicity to aquatic algae was predicted 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5). EC50 growth rate value was estimated to be 179.348 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS: 68083-38-5) was likely to be not toxic to aquatic algae.

The above predicted data of target chemical is supported by the experimental study of structurally similar read across 6-aminonaphthalene- 2-sulphonic acid (CAS No. 93-00-5) from the experimental UERL lab report 2016, suggests that the effect of test item 6- aminonaphthalene-2-sulphonic acid, CAS No. 93-00-5 was studied on the growth of fresh water green alga Chlorella vulgaris. The study was conducted following OECD guideline 201- Alga, growth inhibition test. The test concentration chosen for the study were 6.25 mg/L,12.5 mg/L,25 mg/L,50 mg/L,100 mg/L,200 mg/L. The test concentrations were prepared using stock solution of the test item using mineral media. The green alga was exposed to the test concentration for a period of 72 hours to observe average specific growth rate and % growth inhibition under the effect of the test item. EC50 calculated graphically through probit analysis was observed to be >200 mg/L. Thus, based on this EC50 value and according to CLP Criteria for aquatic classification of the substance, it is concluded that 6-aminonaphthalene-2-sulphonic acid (CAS No.- 93-00-5) does not exhibits toxicity to aquatic algae (Chlorella vulgaris)

Another supporting experimental study for the structurally similar read across 4-amino-3-methylbenzene- sulfonic acid (cas: 98 -33 -9) also suggests that the

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance 4-amino-3- methylbenzenesul- fonic acid according to OECD Guideline 201.The test substance was dissolved in OECD growth medium and tested at the concentrations 0, 0, 30, 45, 67, 100, 150 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (EC50) for the test substance 4-amino-3-methylbenzene- sulfonic acid, in Desmodesmus subspicatus was determined to be 110.6 mg/L

This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as per the CLP criteria.

Thus based on the effect concentrations which is in the range 110.6 mg/l to >200 mg/l give the conclusion that test substance m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS no. 68083 -38 -5) was likely to be not toxic to aquatic invertebrate at environmentally relevant concentrations and can be considered to be “not classified” as per the CLP classification criteria.