Hexa-1,5-diene

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Study period:

23 May 2018

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 adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
EpiSuite (version 4.11)

2. MODEL
ECOSAR (version 1.11)

3. CHEMICAL NAME: 1,5-Hexadiene
CAS#: 592-42-7
SMILES: C(=C)CCC=C

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
The ECOSAR QSAR is a well-established and widely used model that is integrated in the EpiSuite software and is known to be accepted by the European Chemicals Agency (ECHA). As such, the QSAR model is considered to be scientifically valid.

5. APPLICABILITY DOMAIN
The substance adequately falls within the applicability domain of the model.

6. ADEQUACY OF THE RESULT
The predicted result is considered to be adequate for the purpose of classification and labelling and/or risk assessment.

Guideline:

other: REACH Guideline on QSARs R.6

Principles of method if other than guideline:

Mayo-Bean, K. 2012. The ECOSAR (ECOlogical Structure Activity Relationship) Class program for Microsoft Windows. U.S. Environmental Protection Agency, Office of Chemical Safety and Pollution Prevention, MC 7101M, 1200 Pennsylvania Avenue, N.W., Washington, DC 20460.

Specific details on test material used for the study:

SMILES: C(=C)CCC=C

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

7.133 mg/L

Remarks on result:

other: QSAR predicted value

Dose descriptor:

NOEC

Effect conc.:

2.234 mg/L

Remarks on result:

other: QSAR predicted value

ECOSAR (version 1.11) predicted that Hexa-1,5-diene has a 96 hour EC50 value of 7.133 mg/L and a chronic NOEC value of 2.234 mg/L to Green Algae.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
The substance, Hexa-1,5-diene is known to be highly volatile, with an experimental vapour pressure of 29500 Pa (at 25°C) having been reported in the EpiSuite (version 4.11) experimental database. Given the very high volatility of the substance, it is concluded that testing is not technically feasible and as such the ecotoxicity of the substance has instead been predicted via QSAR models.

Description of key information

The substance, Hexa-1,5-diene is known to be highly volatile, with an experimental vapour pressure of 29500 Pa (at 25°C) having been reported in the EpiSuite (version 4.11) experimental database. Given the very high volatility of the substance, it is concluded that testing is not technically feasible and as such the ecotoxicity of the substance has instead been predicted via QSAR models.T

he toxicity of Hexa-1,5-diene to aquatic algae and cyanobacteria has been predicted via the ECOSAR (version 1.11) QSAR within the EpiSuite software (version 4.11). The QSAR model fulfils the OECD principles for QSAR model validation and the substance adequately falls within the applicability domain of the models As such, the prediction results are considered adequate for addressing the toxicity to algae and cyanobacteria data requirement.

 

The predicted toxicity values of Hexa-1,5-diene to green algae were a 96 h EC50 of 7.133 mg/L and a chronic NOEC of 2.234 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

7.133 mg/L

EC10 or NOEC for freshwater algae:

2.234 mg/L