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EC number: 229-043-5 | CAS number: 6407-78-9
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Short-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
- Endpoint:
- short-term toxicity to aquatic invertebrates
- Type of information:
- (Q)SAR
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification
- Justification for type of information:
- QMRF report has been attached
- Qualifier:
- according to guideline
- Guideline:
- other: Estimated data
- Principles of method if other than guideline:
- Prediction was done using the OECD QSAR toolbox version 3.3.
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- - Name of test material (IUPAC name): 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one
- Common name: Solvent Yellow 18
- Molecular formula: C18H18N4O
- Molecular weight: 306.367 g/mol
- Smiles notation: O=C1N(N=C(C)[C@@H]1\N=N\c1c(cc(cc1)C)C)c1ccccc1
- InChl: 1S/C18H18N4O/c1-12-9-10-16(13(2)11-12)19-20-17-14(3)21-22(18(17)23)15-7-5-4-6-8-15/h4-11,17H,1-3H3/b20-19+
- Substance type: Organic
- Physical state: Solid - Analytical monitoring:
- not specified
- Vehicle:
- not specified
- Test organisms (species):
- Daphnia magna
- Details on test organisms:
- - Common name: Water flea
- Test type:
- static
- Water media type:
- freshwater
- Total exposure duration:
- 48 h
- Hardness:
- 250 mg/L expressed as CaCO3
- Test temperature:
- 19.6 - 20.4°C
- pH:
- 7.8 - 7.9
- Dissolved oxygen:
- 8.2 - 8.5 mg/l
- Nominal and measured concentrations:
- Estimated data
- Reference substance (positive control):
- not specified
- Key result
- Duration:
- 48 h
- Dose descriptor:
- EC50
- Effect conc.:
- 109.468 mg/L
- Nominal / measured:
- estimated
- Conc. based on:
- test mat.
- Basis for effect:
- mobility
- Remarks on result:
- other: Other details not known
- Details on results:
- The EC50 was 109.46 mg/l for the exposure period of 48 hrs.
- Validity criteria fulfilled:
- not specified
- Conclusions:
- Based on the immobility of daphnia magna due to the 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one, the EC50 was 109.46 mg/l.
- 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, toxicity on test organism Daphnia magna predicted for 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (6407-78-9). The EC50 value was estimated to be109.46 mg/l when 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5- dihydro-1H- pyrazol-5-one (6407-78-9) is considered to be not toxic to aquatic environment and not classified as per the criteria mentioned in CLP regulation.
Reference
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" or "e" or "f" or "g" )
and ("h"
and (
not "i")
)
)
and ("j"
and (
not "k")
)
)
and "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 "y" )
)
Domain
logical expression index: "a"
Referential
boundary: The
target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion
formation AND SN1 >> Nitrenium Ion formation >> Aromatic azo AND SN1 >>
Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding
by OECD
Domain
logical expression index: "b"
Referential
boundary: The
target chemical should be classified as Schiff base formation AND Schiff
base formation >> Pyrazolones and Pyrazolidinones derivatives AND Schiff
base formation >> Pyrazolones and Pyrazolidinones derivatives >>
Pyrazolones and Pyrazolidinones by Protein binding by OASIS v1.3
Domain
logical expression index: "c"
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 AND SN2 AND SN2 >> SN2
reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom
>> Alkyl diazo by Protein binding by OECD
Domain
logical expression index: "d"
Referential
boundary: The
target chemical should be classified as Amides AND Hydrazines by Aquatic
toxicity classification by ECOSAR
Domain
logical expression index: "e"
Referential
boundary: The
target chemical should be classified as Amides OR Hydrazines by Aquatic
toxicity classification by ECOSAR ONLY
Domain
logical expression index: "f"
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 AND SN2 AND SN2 >> SN2
reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom
>> Alkyl diazo by Protein binding by OECD
Domain
logical expression index: "g"
Referential
boundary: The
target chemical should be classified as Amides AND Hydrazines by Aquatic
toxicity classification by ECOSAR
Domain
logical expression index: "h"
Referential
boundary: The
target chemical should be classified as No alert found by DNA binding by
OASIS v.1.3
Domain
logical expression index: "i"
Referential
boundary: The
target chemical should be classified as AN2 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 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 >>
DNA Intercalators with Carboxamide Side Chain OR Radical 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) 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) >> Nitroarenes with Other
Active Groups 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 reduction and nitrenium ion formation OR
SN1 >> Nucleophilic attack after reduction and nitrenium ion formation
>> Nitroarenes with Other Active Groups OR SN2 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 >> 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 after thiol (glutathione) conjugation OR SN2 >> Nucleophilic
substitution at sp3 carbon atom after thiol (glutathione) conjugation >>
Geminal Polyhaloalkane Derivatives 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: "j"
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 AND SN2 AND SN2 >> SN2
reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom
>> Alkyl diazo by Protein binding by OECD
Domain
logical expression index: "k"
Referential
boundary: The
target chemical should be classified as Acylation >> Direct Acylation
Involving a Leaving group >> Azlactone OR Michael addition OR Michael
addition >> Polarised Alkenes OR Michael addition >> Polarised Alkenes
>> Polarised alkene - ketones OR Michael addition >> Quinones and
Quinone-type Chemicals OR Michael addition >> Quinones and Quinone-type
Chemicals >> Quinone-imine OR No alert found by Protein binding by OECD
Domain
logical expression index: "l"
Referential
boundary: The
target chemical should be classified as Reactive unspecified by Acute
aquatic toxicity MOA by OASIS ONLY
Domain
logical expression index: "m"
Referential
boundary: The
target chemical should be classified as Group 14 - Carbon C AND Group 15
- Nitrogen N AND Group 16 - Oxygen O by Chemical elements
Domain
logical expression index: "n"
Referential
boundary: The
target chemical should be classified as Group 17 - Halogens F by
Chemical elements
Domain
logical expression index: "o"
Referential
boundary: The
target chemical should be classified as Group 14 - Carbon C AND Group 15
- Nitrogen N AND Group 16 - Oxygen O by Chemical elements
Domain
logical expression index: "p"
Referential
boundary: The
target chemical should be classified as Group 16 - Sulfur S by Chemical
elements
Domain
logical expression index: "q"
Referential
boundary: The
target chemical should be classified as Not bioavailable by Lipinski
Rule Oasis ONLY
Domain
logical expression index: "r"
Referential
boundary: The
target chemical should be classified as Alkyl arenes AND Aryl AND Azo
AND Pyrazolone AND Unsaturated heterocyclic amine AND Unsaturated
heterocyclic fragment by Organic Functional groups
Domain
logical expression index: "s"
Referential
boundary: The
target chemical should be classified as Alkoxy by Organic Functional
groups
Domain
logical expression index: "t"
Referential
boundary: The
target chemical should be classified as Aliphatic Carbon [CH] AND
Aliphatic Carbon [-CH2-] AND Aliphatic Carbon [-CH3] AND Aliphatic
Nitrogen, one aromatic attach [-N] AND Amide, aliphatic attach [-C(=O)N]
AND Amino, aliphatic attach [-N<] AND Amino-carbonyl compound
[NCC(=O)-C] AND Aromatic Carbon [C] AND Azo [-N=N-] AND Azomethine,
aliphatic attach [-N=C] AND Carbonyl, aliphatic attach [-C(=O)-] AND
Hydrazine [>N-N<] AND Miscellaneous sulfide (=S) or oxide (=O) AND
Nitrogen, two or tree olefinic attach [>N-] AND Olefinic carbon [=CH- or
=C<] by Organic functional groups (US EPA)
Domain
logical expression index: "u"
Referential
boundary: The
target chemical should be classified as Carbonyl, one aromatic attach
[-C(=O)-] by Organic functional groups (US EPA)
Domain
logical expression index: "v"
Referential
boundary: The
target chemical should be classified as AN2 AND AN2 >> Michael addition
to activated double bonds in heterocyclic ring systems AND AN2 >>
Michael addition to activated double bonds in heterocyclic ring systems
>> Pyrazolone and Pyrazolidine Derivatives AND AN2 >> Shiff base
formation with carbonyl compounds AND AN2 >> Shiff base formation with
carbonyl compounds >> Pyrazolone and Pyrazolidine Derivatives by Protein
binding alerts for Chromosomal aberration by OASIS v1.1
Domain
logical expression index: "w"
Referential
boundary: The
target chemical should be classified as AN2 >> Michael-type addition to
quinoid structures >> Carboxylic Acid Amines by Protein binding alerts
for Chromosomal aberration by OASIS v1.1
Domain
logical expression index: "x"
Parametric
boundary:The
target chemical should have a value of log Kow which is >= 4.84
Domain
logical expression index: "y"
Parametric
boundary:The
target chemical should have a value of log Kow which is <= 7.54
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, toxicity on test organism Daphnia magna predicted for 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (6407-78-9). The EC50 value was estimated to be109.46 mg/l when 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5- dihydro-1H- pyrazol-5-one (6407-78-9) is considered to be not toxic to aquatic environment and not classified as per the criteria mentioned in CLP regulation.
Key value for chemical safety assessment
Fresh water invertebrates
Fresh water invertebrates
- Effect concentration:
- 109.46 mg/L
Additional information
Various predicted data for the target compound 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (6407-78-9) and experimental data for supporting weight of evidence studies for its closest read across substance with log Kow as the primary descriptor and on the basis of structural and functional similarity study were reviewed for the toxicity on the invertebrates end point which are summarized as below:
In a prediction done by SSS (2017), 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, toxicity on test organism Daphnia magna predicted for 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (6407-78-9). The EC50 value was estimated to be109.46 mg/l when 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5- dihydro-1H- pyrazol-5-one (6407-78-9) is considered to be not toxic to aquatic environment and not classified as per the criteria mentioned in CLP regulation.
First predicted study was supported by the structurally similar read across chemical (85-83-6) study were to determine the toxicity of a chemical. Determination of the inhibition of the mobility of daphnids was carried out with the substance 1-(2-Methyl-4-(2-methylphenylazo)phenylazo)-2-naphthol. Test was conducted according to OECD Guideline 202. The stock solution 2 g/L was prepared by dissolving brown powder in acetone. Test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance was tested at the concentrations 0, 0, 0.6, 1.2, 2.5, 5, 10 mg/l nominal concentrations. Effects on immobilisation were observed for 48 hours. The median effective concentration (EC50) for the test substance, 1-(2-Methyl-4-(2-methylphenylazo)phenylazo)-2-naphthol, in Daphnia magna was determined to be 3.9 mg/L. This value indicates that the substance is likely to be hazardous to aquatic algae and can be classified as aquatic chronic 2 as per the CLP criteria. But as the chemical was readily biodegradable in water so on the basis of biodegradability, it can be concluded that the chemical 1-(2-Methyl-4-(2-methylphenylazo) phenylazo)-2-naphthol was nontoxic and can be consider to be not classified as per the CLP classification criteria.
Similarly in the third weight of evidence study for the functionally similar read across chemical (12225-21-7) from ABITEC report 2017. Determination of the inhibition of the mobility of daphnids was carried out with the substance Aluminium,4,5-dihydro-5-oxo-1-(4-sulfophenyl)-4-[(4-sulfophenyl)azo]-1H-pyrazole- 3-carboxylic acid complex (CAS No12225-21-7) according to OECD Guideline 202. The test substance was tested at the concentrations 0, 50, 70, 100, 140, 200 mg/L. Effects on immobilisation were observed for 48 hours. The median effective concentration (EC50) for the test substance Aluminium, 4,5-dihydro-5-oxo-1-(4-sulfophenyl)-4-[(4-sulfophenyl)azo]-1H-pyrazole-3-carboxylic acid complex (CAS No12225-21-7) in Daphnia magna was determined to be 360.4 mg/L for immobilisation effects. This value indicates that the Aluminium,4,5-dihydro-5-oxo-1-(4-sulfophenyl) -4-[(4-sulfophenyl)azo]-1H-pyrazole-3-carboxylic acid complex (CAS No12225-21-7) is likely to be non-hazardous to aquatic invertebrates and can be classified as "not classified" as per the CLP criteria.
On the basis of above results for target chemical 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (6407-78-9) (from OECD QSAR toolbox version 3.3) and for its read across substance from ABITEC 2017, it can be concluded that the test substance 4-[(E)-2-(2,4-dimethylphenyl) diazen-1-yl]-3-methyl-1-phenyl- 4,5-dihydro-1H-pyrazol-5-one (6407-78-9) is nontoxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.
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