5-methyl-3-phenylisoxazole-4-carbonyl chloride

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 the 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 : 5-methyl-3-phenylisoxazole-4-carbonyl chloride
- Molecular formula : C11H8ClNO2
- Molecular weight : 221.642 g/mole
- Smiles notation : c1(ccccc1)c1c(C(=O)Cl)c(on1)C
- InChl : 1S/C11H8ClNO2/c1-7-9(11(12)14)10(13-15-7)8-5-3-2-4-6-8/h2-6H,1H3
- Substance type: Organic
- Physical state: Solid

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

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

Details on test organisms:

No data available

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Test temperature:

24 ± 1°C

pH:

7.5 ± 0.1

Dissolved oxygen:

No data available

Salinity:

No data available

Conductivity:

No data available

Nominal and measured concentrations:

Estimated data

Details on test conditions:

No data available

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

134.557 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Other details not known

Details on results:

No data available

Results with reference substance (positive control):

No data available

Reported statistics and error estimates:

No data available

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 "f" )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and ("m" and "n" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Acyl halide OR Allyl OR Aryl OR Ketoxime derivatives OR Oxazole/ Izoxazole by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Acyl halide OR Allyl OR Aryl OR Ketoxime derivatives OR Overlapping groups OR Oxazole/ Izoxazole by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aromatic Carbon [C] OR Aromatic Nitrogen, five-member ring OR Aromatic Oxygen OR Carbonyl, olefinic attach [-C(=O)-] OR Chlorine, olefinic attach [-Cl] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] OR Oxygen, nitrogen attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

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

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Class 3 (unspecific reactivity) by Acute aquatic toxicity classification by Verhaar (Modified) ONLY

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Reactive unspecified by Acute aquatic toxicity MOA by OASIS ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Acyl halides AND alpha,beta-unsaturated carbonyls AND H-acceptor-path3-H-acceptor by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Primary aromatic amine, hydroxyl amine and its derived esters by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules by Keratinocyte gene expression

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as High gene expression OR High gene expression >> Activated esters OR Low gene expression OR Low gene expression >> Methacrylate esters OR Moderate gene expression OR Moderate gene expression >> Acrylate esters by Keratinocyte gene expression

Domain logical expression index: "k"

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

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Not classified by Oncologic Primary Classification

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of log Kow which is >= 1.11

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of log Kow which is <= 2.4

Validity criteria fulfilled:

not specified

Conclusions:

Based on the growth inhibition of Pseudokirchneriella subcapitata, due to the exposure of chemical 5-methyl-3-phenylisoxazole-4-carbonyl chloride, the EC50 was 134.557 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, the toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for Target substance 5-methyl-3- phenylisoxazole-4-carbonyl chloride (16883-16-2). EC50 value was estimated to be 134.557 mg/l for Species Pseudokirchneriella subcapitata for 72 hrs duration when exposed to 5-methyl-3-phenylisoxazole-4-carbonyl chloride.

Based on this value it can be concluded that the substance5-methyl-3-phenylisoxazole-4-carbonyl chlorideis considered as nontoxic to aquatic environment as per the criteria mentioned in CLP regulation. 

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, the toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for Target substance 5-methyl-3- phenylisoxazole-4-carbonyl chloride (16883-16-2). EC50 value was estimated to be 134.557 mg/l for Species Pseudokirchneriella subcapitata for 72 hrs duration when exposed to 5-methyl-3-phenylisoxazole-4-carbonyl chloride.

Based on this value it can be concluded that the substance5-methyl-3-phenylisoxazole-4-carbonyl chlorideis considered as nontoxic to aquatic environment as per the criteria mentioned in CLP regulation. 

Key value for chemical safety assessment

EC50 for freshwater algae:

134.557 mg/L

Additional information

Based on the various experimental data and prediction data for the target chemical as well as RA chemical which was selected on the basis of structure similarity study have been reviewed to determine the toxic nature of 5-methyl-3-phenylisoxazole-4-carbonyl chloride (16883-16-2) on the growth of algae. The studies are as mentioned below:

In the first predicted weight of evidence report for the 5-methyl-3-phenylisoxazole-4-carbonyl chloride (16883-16-2) from SSS (QSAR, 2017) toxicity study was carried out. 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, the toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for Target substance 5-methyl-3- phenylisoxazole-4-carbonyl chloride (16883-16-2). EC50 value was estimated to be 134.557 mg/l for Species Pseudokirchneriella subcapitata for 72 hrs duration when exposed to 5-methyl-3-phenylisoxazole-4-carbonyl chloride. Based on this value it can be concluded that the substance5-methyl-3-phenylisoxazole-4-carbonyl chloride is considered as nontoxic to aquatic environment as per the criteria mentioned in CLP regulation. 

 

Similarly in the second weight of evidence study for the read across chemical (98-85-1) (from ABITEC lab, 2016), Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance 1-phenylethanol according to OECD Guideline 201. The test substance was dissolved in DMSO and tested at the concentrations 0 and 100 mg/L. Effects on the growth rate of the organism were studied. Based on the growth inhibition of green algae Desmodesmus subspicatus, due to the 1-phenylethanol, the IC1.5 was 100 mg/l. Thus median effective concentration (EC50) for the test substance, 1-phenylethanol, in Desmodesmus subspicatus was determined to be > 100 mg/L. This value indicates that the substance is not likely to be hazardous to aquatic algae as per the CLP criteria.

 

Similarly in the third weight of evidence study for the read across chemical (79-10-7), from HSDB and ECOTOX, 2017, Determination of short term toxicity of 2-hydroxyethyl methacrylate on the growth of Chlorococcales (green algae). Test performed by providing the incubation period of 24hrs. Static method was used to observe the effect on Chlorococcales. After the incubation of 24hrs physiological effect was observed which was measured by Assimilation efficiency. Thus based on the physiological effect measured by Assimilation efficiency, the EC50 was 118 mg/l. Thus it was concluded that the chemical was nontoxic and can be consider to be not classified as toxic as per the CLP classification criteria.

 

In the fourth weight of evidence study for the read across chemical (110-16-7) from GSBL database 2017, toxicity was studied. Determination of short term toxicity of (2Z)-but-2-enedioic acid to aquatic algae Haematococcus pluvialis carried out for 4 hrs. Test was carried out in the Warburg apparatus and is based on the methods of tubercle. The initial cell count in the test is 80000 cells / ml. based on the effect on cell proliferation and inhibition of oxygen production of algae due to the chemical, the EC50 was 125 mg/l. Thus (2Z)-but-2-enedioic acid was consider as nontoxic and can be consider to be not classified as toxic as per the CLP classification criteria.

  

 

Thus based on the above data sources for target chemical 5-methyl-3-phenylisoxazole-4-carbonyl chloride (16883-16-2) from various experimental studies and predicted studies from QSAR, ABITEC report, GSBL, HSDB and ECOTOX, it was summarized that the chemical was nontoxic and can be consider to be not classified as toxic as per the CLP classification criteria.