3,7-dimethylocta-2,6-dienyl acetate

Auto flammability

Description of key information

The autoflammability is 245°C based on read across from Citronellyl acetate, the rationale is presented below.

Key value for chemical safety assessment

Autoflammability / Self-ignition temperature at 101 325 Pa:

245 °C

Additional information

Auto-flammability of Neryl acetate multi using read across from Citronellyl acetate multi

 

Introduction

Neryl acetate multi is a multi-constituent of two isomers: Neryl acetate and Geranyl acetate. This ester has an unsaturated branched alkyl backbone to which an acetate group is attached. For this substance there is no experimental auto-flammability information available. According to REACH Annex XI 1.5, information can be generated by other means, i.e. applying alternative methods such as QSARs, grouping and read-across. The autoflammability information of Citronellyl acetate is used to predict the auto-flammability of Neryl acetate multi.

Hypothesis: Neryl acetate multi has the same auto-flammability as Citronelly acetate.

Available information: Citronellyl acetate is tested in an A15 (Rel. 1) test and has an experimental auto-flammability temperature of 245°C.

Target chemical and source chemical(s)

Chemical structures of the target chemical and the source chemical(s) are shown in the data matrix, including relevant physico-chemical properties.

Purity / Impurities

Neryl acetate multi is a multi-constituent. The other component is the E-isomer Geranyl acetate, together these have a purity of > 80%. There is one known impurity below << 10%, similar to the Neryl acetate and therefore will not be considered further. 

Analogue justification

According to Annex XI 1.5 read across can be used to replace testing when the similarity can be based on a common backbone and a common functional group. When using read across the result derived should be applicable for C&L and/or risk assessment and it should be presented with adequate and reliable documentation, which is presented below.

Analogue selection: For Neryl acetate multi the substance Citronellyl acetate multi was selected, because it is a close analogue and auto-flammability information was readily available.

Structural similarities and differences: Neryl acetate multi and Citronellyl acetate both have a similar unsaturated branched alkyl backbone to which acetate-group is attached. The difference is that Citronellyl acetate has one double bond less and therefore two additional H-atoms. The minor constituent of Citronellyl acetate, Dihydro-Citronellyl acetate has no double bonds in its chemical structure, which adds another two H-atoms.

Physical chemical properties: For liquids the boiling point and flashpoint are the key features for flammability. Both these properties are similar for Neryl acetate multi and Citronellyl acetate multi: the boiling points are 247.6 and 244°C, respectively and flashpoints are 98 and 104°C, respectively. Based on these similarities for Neryl acetate multi a similar auto-flammability as for Citronellyl acetate can be predicted and results in a value of 245°C value.

Uncertainty of the predictions: There are no remaining uncertainties other than those already addressed above.

Conclusion on hazard

For Neryl acetate multi no experimental information is available for auto-flammability but for Citronellyl acetate multi, a close analogue, such information is available and is 245°C, which can be used for read across.

Final conclusion: Neryl acetate multi has an auto-flammability 245°C.

 

Data matrix: Neryl acetate multi’s characteristics and expected autoflammability supported with experimental data from Citronellyl acetate

Common names	Neryl acetate multi (Z and E-isomer)	Citronellyl acetate multi (Key constituent)
	Target	Source
Chemical structures	One of the isomers
CAS no.	16409-44-2	150-84-5 (Citronellyl acetate),
Empirical formula	C12H20O2	C12H22O2
EINECS	240-458-0 (mono)	908-114-0
REACH Registration	2018	2018
Molecular weight	196	198
Phys-Chem
Physical state	Liquid	Liquid
Boiling point oC	247.6	244
Vapour pressure in Pa	2.1	2.58
Flashpoint oC	98	104
Viscosity mPa	1.97	2.1
Auto-flammability (°C)	245 (Read across)	245 (EC A.15)