Allyl butyrate

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 QMRAF 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): 2-Propen-1-yl butanoate
- Common name: Allyl butyrate
- Molecular formula: C7H12O2
- Molecular weight: 128.17 g/mol
- Smiles notation: C(OCC=C)(CCC)=O
- InChl: 1S/C7H12O2/c1-3-5-7(8)9-6-4-2/h4H,2-3,5-6H2,1H3
- Substance type: Organic
- Physical state: Liquid

Analytical monitoring:

not specified

Details on sampling:

No data available

Vehicle:

not specified

Details on test solutions:

No data available

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

Remarks on exposure duration:

No data available

Post exposure observation period:

No data available

Salinity:

No data available

Conductivity:

No data available

Nominal and measured concentrations:

No data available

Details on test conditions:

No data available

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

148.84 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Nontoxic

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 ( not "f") )  )  and "g" )  and "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" )  )

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 Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "f"

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 Strong binder, OH group OR Weak binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "g"

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

Domain logical expression index: "h"

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: "i"

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

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Acid moiety OR Acrylates OR Halo Ester OR Methacrylates by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as -C=CH  [alkenyl hydrogen] AND -CH2-  [linear] AND Ester   [-C(=O)-O-C] AND Methyl  [-CH3] by Bioaccumulation - metabolism alerts

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Carbon with 4 single bonds & no hydrogens by Bioaccumulation - metabolism alerts

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Alkene AND Allyl AND Carboxylic acid ester by Organic Functional groups

Domain logical expression index: "n"

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

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Alkene AND Allyl AND Carboxylic acid ester by Organic Functional groups

Domain logical expression index: "p"

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

Domain logical expression index: "q"

Parametric boundary:The target chemical should have a value of log Kow which is >= 1.36

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is <= 2.83

Validity criteria fulfilled:

not specified

Conclusions:

Based on the growth inhibition of green algae Pseudokirchneriella subcapitata due to the exposure of chemical 2-Propen-1-yl butanoate (allyl butyrate) the EC50 was 148.840 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 Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) predicted for 2-Propen-1-yl butanoate (allyl butyrate). The EC50 value was estimated to be 148.840 mg/l when 2-Propen-1-yl butanoate (allyl butyrate)exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)for 72 hrs.

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 Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) predicted for 2-Propen-1-yl butanoate (allyl butyrate). The EC50 value was estimated to be 148.840 mg/l when 2-Propen-1-yl butanoate (allyl butyrate)exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)for 72 hrs.

Key value for chemical safety assessment

EC50 for freshwater algae:

148.84 mg/L

Additional information

Based on the various experimental data and prediction data for the target chemical study have been reviewed to determine the toxic nature of Allyl butyrate (2051-78-7) on the growth of aquatic algae and cyanobacteria. The studies are as mentioned below:

 

In the first weight of evidence study for the chemical allyl butyrate, QSAR 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 Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) predicted for 2-Propen-1-yl butanoate (allyl butyrate). The EC50 value was estimated to be 148.840 mg/l when 2-Propen-1-yl butanoate (allyl butyrate)exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)for 72 hrs.

In the second experimental weight of evidence study for the RA chemical (105-54-4) from ABITEC report 2017, Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance Ethyl butyrate according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the concentrations 100 mg/L. Effects on the growth rate of the organism were studied. The Inhibitory concentration IC1.5 for the test substance, Ethyl butyrate, in Desmodesmus subspicatus was determined to be 100 mg/L on the basis of effects on growth rate in a 72 hour study. This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as toxic as per the CLP criteria.

 

Similarly in the third weight of evidence study for the second RA chemical (112-14-1) from ABITEC report study was carried out for the determination of the inhibition of the mobility of daphnids by the exposure with the substance Octyl Acetate. Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance Octyl Acetate according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the limit concentration of 100 mg/l. Effects on the growth rate of the organism were studied. The effective concentration (EC2.1) for the test substance, Octyl Acetate, in Desmodesmus subspicatus was determined to be 100 mg/L. As the limit test was performed at 100 mg/l where only 2.1% inhibition of algal cells was occurred. Thus it was estimated that the EC50 concentration was greater than 100 mg/l. Based on this EC2.1 % inhibition value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the substance Octyl Acetate does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus) and cannot be classified as toxic as per the CLP classification criteria.

 

Similarly in the fourth weight of evidence study for the RA chemical (105-54-4) from HSDB and ECOTOX databases, 2017, Short term toxicity to Chlorococcales (green algae) study was carried out for 24 hrs.The study was based on the effects of the test compound Ethyl butyrate (CAS no. 105 -54 -4) on green algae in a static fresh water system. Based on effect on physiology of the test organism Chlorococcales (green algae), the 24 hr EC50 value was determined to be 1000 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance Ethyl butyrate can be considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

 

Based on the data obtain from various predicted and experimental studies for the toxicity on aquatic algae due to the exposure of Allyl butyrate (2051-78-7) thus it was concluded that the chemical Allyl butyrate was consider as nontoxic and can be consider to be not classified as toxic to aquatic algae and cyanobacteria as per CLP classification criteria.