Allyl propionate

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:

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

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:

no

Specific details on test material used for the study:

- Name of the test material: 2-Propenyl Propanoate
- IUPAC name: 2-Propenyl Propanoate
- Molecular formula: C6H10O2
- Molecular weight: 114.143 g/mol
- Substance type: Organic
- Physical State: Liquid
- Smiles: CCC(=O)OCC=C
- InChI: 1S/C6H10O2/c1-3-5-8-6(7)4-2/h3H,1,4-5H2,2H3

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

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

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

189.73 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 "n" )  and ("o" and ( not "p") )  )  and "q" )  and ("r" and ( not "s") )  )  and "t" )  and ("u" and "v" )  )

Domain logical expression index: "a"

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

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as SN2 AND SN2 >> SN2 Reaction at a sp3 carbon atom AND SN2 >> SN2 Reaction at a sp3 carbon atom >> Activated alkyl esters and thioesters  by Protein binding by OASIS v1.3

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as SN2 AND SN2 >> SN2 reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom >> Allyl acetates and related chemicals by Protein binding by OECD

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Esters AND Vinyl/Allyl Esters by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "e"

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

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Isocyanates and Isothiocyanates OR Acylation >> Isocyanates and Isothiocyanates >> Isocyanates OR 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 >> Arenes OR Michael addition >> Polarised Alkenes-Michael addition OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated esters OR SN1 OR SN1 >> Carbenium Ion Formation OR SN1 >> Carbenium Ion Formation >> Alpha halo ethers (including alpha halo thioethers) OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion Formation >> Aliphatic tertiary amines OR SN2 OR SN2 >> Direct Acting Epoxides and related OR SN2 >> Direct Acting Epoxides and related >> Epoxides by DNA binding by OECD

Domain logical expression index: "g"

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: "h"

Referential boundary: The target chemical should be classified as High reactive OR High reactive >> Activated haloarenes OR High reactive >> alpha,beta-carbonyl compounds with polarized multiple bonds OR High reactive >> Thiols OR Low reactive OR Low reactive >> Alicyclic ketones by DPRA Cysteine peptide depletion

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "j"

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

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules (GSH) by Protein binding potency

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Highly reactive (GSH) OR Highly reactive (GSH) >> Alkyl 2-chloroacetoacetates (SN2) OR Highly reactive (GSH) >> Miscellaneous Alkyl 2-halo alkenoates (SN2) by Protein binding potency

Domain logical expression index: "m"

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

Domain logical expression index: "n"

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: "o"

Referential boundary: The target chemical should be classified as Esters AND Vinyl/Allyl Esters by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Halo Ester by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Very fast by Bioaccumulation - metabolism half-lives ONLY

Domain logical expression index: "r"

Referential boundary: The target chemical should be classified as No alert found by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as alpha,beta-unsaturated aliphatic alkoxy group (Genotox) OR Structural alert for genotoxic carcinogenicity by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "t"

Similarity boundary:Target: CCC(=O)OCC=C
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "u"

Parametric boundary:The target chemical should have a value of log Kow which is >= 1.01

Domain logical expression index: "v"

Parametric boundary:The target chemical should have a value of log Kow which is <= 2.18

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 on algae was predicted 2-Propenyl Propanoate (CAS: 2408-20-0). Effect concentration i.e EC50 value was estimated to be 189.73 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that the 2-Propenyl Propanoate (CAS: 2408-20-0) was likely to be not toxic to aquatic algae hence it can be considered to be “not Classified” as per the CLP classification criteria for aquatic environment.

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 on algae was predicted 2-Propenyl Propanoate (CAS: 2408-20-0). Effect concentration i.e EC50 value was estimated to be 189.73 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that the 2-Propenyl Propanoate (CAS: 2408-20-0) was likely to be not toxic to aquatic algae hence it can be considered to be “not Classified” as per the CLP classification criteria for aquatic environment.

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 on algae was predicted 2-Propenyl Propanoate (CAS: 2408-20-0). Effect concentration i.e EC50 value was estimated to be 189.73 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that the 2-Propenyl Propanoate (CAS: 2408-20-0) was likely to be not toxic to aquatic algae hence it can be considered to be “not Classified” as per the CLP classification criteria for aquatic environment.

Key value for chemical safety assessment

EC50 for freshwater algae:

189.73 mg/L

Additional information

Following studies include the predicted data and experimental study for the target chemical and structurally similar read across to conclude the 2-Propenyl Propanoate (CAS: 2408-20-0) toxicity towards aquatic 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 on algae was predicted 2-Propenyl Propanoate (CAS: 2408-20-0). Effect concentration i.e EC50 value was estimated to be 189.73 mg/l for Pseudokirchneriella subcapitata for 72 hrs duration. It was concluded that the 2-Propenyl Propanoate (CAS: 2408-20-0) was likely to be not toxic to aquatic algae.

The above predicted data is supported by the experimental study of structurally similar read across ethyl butyrate (CAS:105-54-4) from publication Water research, 1980 suggests that the Short term toxicity to Entosiphon Sulcatum study was carried out for 72 hrs. The study was based on the effects of the test compound Ethyl butyrate on Entosiphon Sulcatum in a static fresh water system. Test chemical of known concentration was prepared in sterile double distilled water. For maintenance of the test strain of Entosiphon sulcatum,continuously inoculate the expected required number of stock cultures at 72 h or 96 h intervals. For this, mix 8 ml of stock solution I and 8 ml of sterile double-distilled water in 300 -ml Erlenmeyer flasks stoppered with metal caps and add 2 ml of a stock culture and 2 ml of the adjusted bacterial suspension for Entosiphon stock cultures. Store stock cultures at 25°C. Before inoculation control the flasks containing the stock cultures by means of an inverse microscope. Escherichia coli was used as a feeding material of the test organism Entosiphon sulcatum.

Prepare two parallel dilution series in 300-ml Erlenmeyer flasks stoppered with metal caps. The dilutions will contain 1 part v/v each of pollutant solution in 2⁰to 2¹⁴partsv/vof mixture. Test vessel contain the known conc. of chemical and test organism. Leave the test culture at 25ᵒC for 72 hrs. Before measurement, control each flask by means of an inverse microscope. Add 10% of a 1.1% NaNO3 solution in double-distilled water filtered through a membrane filter (pore size 0.2/µm), and determine the number of protozoaby means of a cell counter. Pollutant concentrations at which the onset of inhibitory action was observed have been obtained by mathematical evaluation of counts. The term counts corresponds to impulses indicated by the coulter counter. Based on the onset of the inhibitory effect on population of the test organism Entosiphon Sulcatum, the 72 hr LOEC value was determined to be 236 mg/lIt can be conlcuded from the value that the ethyl butyrate is not toxic to the aquatic algae.

Similar experimental study for another structurally similar read across Methyl propionate(CAS; 554-12-1) from publication water research 1990, inidicates that In the Scenedesmus cell multiplication inhibition test, hazardous substances were examined to determine the effect concentrations (EC). The tests were conducted in accordance with the test procedure DIN 38 412, Part 9 (draft standard). The green alga Scenedesmus subspicatus CHODAT was cultivated as the test organism. Decreasing trend of Population changes effect were measured.

The Effective concentration EC50 to 50% of Scenedesmus subspicatus is 500 mg/l. It can be concluded that the Methyl propionate is not toxic to the aquatic algae.

Thus based on the effect concentrations which is in the range 189.73 mg/l to 500 mg/Lgive the conclusion that test substance 2-Propenyl Propanoate (CAS: 2408-20-0) was likely to be not toxic to aquatic algae at environmentally relevant concentrations and applying the weight of evidence approach it can be considered to be“not classified”as per the CLP classification criteria.