[1R-(1α,2α,5β,8β)]-4,4,8-trimethyltricyclo[6.3.1.02,5]dodecan-1-yl acetate

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:

QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Estimated data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material : [1R-(1α, 2α, 5β, 8β)]-4, 4, 8-trimethyltricyclo [6.3.1.02, 5] dodecan-1-yl acetate
- Molecular formula : C17H28O2
- Molecular weight : 264.4062 g/mol
- Smiles notation : CC(=O)O[C@@]12CCC[C@@](C)(CC[C@@H] 3[C@@H]1CC3(C)C)C2
- InChl : 1S/C17H28O2/c1-12(18)19-17-8-5-7-16(4,11-17)9-6-13-14(17)10-15(13,2)3/h13-14H,5-11H2,1-4H3/t13-,14+,16+,17-/m1/s1
- Substance type: Organic
- Physical state: Liquid

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

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

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Test temperature:

22.6 - 23.9 °C

pH:

6.75 - 8.56

Nominal and measured concentrations:

Estimated data

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.376 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:

The EC50 was 0.37 mg/l after the exposure of chemical for 72hrs.

The prediction was based on dataset comprised from the following descriptors: EC50
Estimation method: Takes average value from the 6 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((((((("a" or "b" or "c" or "d" or "e" )  and ("f" and ( not "g") )  )  and ("h" and ( not "i") )  )  and "j" )  and "k" )  and "l" )  and "m" )  and ("n" and ( not "o") )  )  and "p" )  and ("q" and ( not "r") )  )  and ("s" and ( not "t") )  )  and ("u" and "v" )  )

Domain logical expression index: "a"

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

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as AN2 AND AN2 >> Shiff base formation after aldehyde release AND AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters AND SN1 AND SN1 >> Nucleophilic attack after carbenium ion formation AND SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters AND SN2 AND SN2 >> Acylation AND SN2 >> Acylation >> Specific Acetate Esters AND SN2 >> Nucleophilic substitution at sp3 Carbon atom AND SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters by DNA binding by OASIS v.1.3

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 by Protein binding by OECD

Domain logical expression index: "d"

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

Domain logical expression index: "e"

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

Domain logical expression index: "f"

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

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as 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 amides 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 SN1 >> Nitrenium Ion formation OR SN1 >> Nitrenium Ion formation >> Aromatic azo OR SN1 >> Nitrenium Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo OR SN2 OR SN2 >> Direct Acting Epoxides and related OR SN2 >> Direct Acting Epoxides and related >> Epoxides OR SN2 >> SN2 at an sp3 Carbon atom OR SN2 >> SN2 at an sp3 Carbon atom >> Aliphatic halides by DNA binding by OECD

Domain logical expression index: "h"

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: "i"

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 OR Low reactive >> N-substituted aromatic amides OR Low reactive >> Saturated acid anhydrides by DPRA Cysteine peptide depletion

Domain logical expression index: "j"

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

Domain logical expression index: "k"

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: "l"

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: "m"

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

Domain logical expression index: "n"

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

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Aliphatic Amines OR Halo Ester OR Surfactants-Nonionic OR Vinyl/Allyl Esters by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Not bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Acetoxy AND Alkane, branched with tertiary carbon AND Bridged-ring carbocycles AND Carboxylic acid ester AND Cycloalkane AND Fused saturated carbocycles by Organic Functional groups

Domain logical expression index: "r"

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

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as Acetoxy AND Alkane, branched with tertiary carbon AND Carboxylic acid ester AND Cycloalkane AND Overlapping groups by Organic Functional groups (nested)

Domain logical expression index: "t"

Referential boundary: The target chemical should be classified as Glycerol and derivatives by Organic Functional groups (nested)

Domain logical expression index: "u"

Parametric boundary:The target chemical should have a value of log Kow which is >= 5.07

Domain logical expression index: "v"

Parametric boundary:The target chemical should have a value of log Kow which is <= 8.51

Validity criteria fulfilled:

not specified

Conclusions:

Based on the growth rate inhibition of algae, the EC50 value was estimated to be 0.3 mg/l when (1R-(1alpha,2alpha,5beta,8beta)) -4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate exposed to Pseudokirchneriella subcapitata for 72hrs.

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 six closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for (1R-(1alpha,2alpha,5beta,8beta))-4,4,8-Trimethyltricyclo [6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3). Based on the growth rate inhibition of algae, the EC50 value was estimated to be 0.3 mg/l when (1R-(1alpha,2alpha,5beta,8beta)) -4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate exposed to Pseudokirchneriella subcapitata for 72hrs. Based on this value it can be concluded that the substance (1R-(1alpha,2alpha, -5beta,8beta))-4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3) is considered to be toxic to aquatic environment and can be classified as aquatic acute 1 / chronic 1 category 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 six closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for (1R-(1alpha,2alpha,5beta,8beta))-4,4,8-Trimethyltricyclo [6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3). Based on the growth rate inhibition of algae, the EC50 value was estimated to be 0.37mg/l when (1R-(1alpha,2alpha,5beta,8beta)) -4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate exposed to Pseudokirchneriella subcapitata for 72hrs. Based on this value it can be concluded that the substance (1R-(1alpha,2alpha, -5beta,8beta))-4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3) is considered to be toxic to aquatic environment and can be classified as aquatic acute 1 / chronic 1 category per the criteria mentioned in CLP regulation. 

Key value for chemical safety assessment

EC50 for freshwater algae:

0.3 mg/L

Additional information

Based on the prediction data for the target chemical study have been reviewed to determine the toxic nature of (1R-(1alpha,2alpha,5beta,8beta))-4,4,8-Trimethyltricyclo [6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3) on the growth of aquatic algae and cyanobacteria. The studies are as mentioned below: 

 

In the first predicted report for the target chemical, based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for (1R-(1alpha,2alpha,5beta,8beta))-4,4,8-Trimethyltricyclo [6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3). Based on the growth rate inhibition of algae, the EC50 value was estimated to be 0.3 mg/l when (1R-(1alpha,2alpha,5beta,8beta)) -4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate exposed to Pseudokirchneriella subcapitata for 72hrs. Based on this value it can be concluded that the substance (1R-(1alpha,2alpha, -5beta,8beta))-4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3) is considered to be toxic to aquatic environment and can be classified as aquatic acute 1 / chronic 1 category per the criteria mentioned in CLP regulation. 

 

Similarly second weight of evidence study conducted by using prediction done by EPI suite, ECOSAR version 1.1. Based on the prediction done using the EPI Suite ECOSAR version 1.10, the short term toxicity on green algae was predicted for test substance  (1R-(1alpha,2alpha,5beta,8beta)) -4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 0.404 mg/l for green algae Species for 96 hrs duration. Based on this value, it can be concluded that the test chemical  (1R-(1alpha,2alpha,5beta,8beta) )-4,4,8-Trimethyltricyclo[6.3.1.02,5]dodecanyl acetate (CAS No. 57082 -24 -3) can be considered as toxic to green algae at environmentally relevant concentrations and can be considered to be classified in aquatic acute1 / chronic 1 as per the CLP classification criteria.

 

Thus based on the toxicity effect of chemical on the growth of algae, (1R-(1alpha,2alpha, 5beta,8beta))-4,4,8-Trimethyltricyclo [6.3.1.02,5]dodecanyl acetate is considered to be toxic to aquatic environment and can be classified as aquatic acute 1 as well as chronic 1 as per the criteria mentioned in CLP regulation.