Fatty acids, C9, hexaesters with dipentaerythritol

Endpoint summary

Key value for chemical safety assessment

Absorption rate - oral (%):

50

Absorption rate - dermal (%):

50

Absorption rate - inhalation (%):

100

Additional information

No information could be identified on the toxicokinetics of the test substance. In accordance with ECHA Guidance R.7c (ECHA, 2012), an estimation of the toxicokinetic behaviour can be made based on available information on physicochemical and toxicological characteristics of the substance. Fatty acids, C9, tetraesters with dipentaerythritol is a UVCB. It is poorly water soluble (< 0.1 mg/L) and has a molecular weight >500 g/mol, a log Pow of > 10 based on (Q)SAR modeling and a vapour pressure close to 0 Pa at 20°C.

 

Absorption

Absorption is a function of the potential for a substance to diffuse across biological membranes. The most useful parameters providing information on this potential are molecular weight, octanol/water partition coefficient (log Pow) and water solubility.

 

Oral

The smaller the molecule, the more easily it will be taken up. In general, molecular weights below 500 g/mol favor oral absorption. As the molecular weight of the substance is > 500 g/mol, absorption in the gastrointestinal tract is likely to be limited. Also, the log Pow of >10 suggests that the absorption of such a highly lipophilic substance may be limited by the inability to dissolve into gastrointestinal (GI) fluids. It might be enhanced by micellar solubilisation, as this mechanism is of importance for highly lipophilic substances (log Pow >4), which are poorly soluble in water (1 mg/L or less). However, for large molecules, gastrointestinal absorption is not likely to occur.

In the absence of substance-specific information, the default oral absorption value of 50% is considered for DNEL derivation.

 

 

Dermal

The smaller the molecule, the more easily it may be taken up. In general, a molecular weight below 100 g/mol favors dermal absorption, above 500 g/mol the molecule may be too large. As the molecular weight of the substance is > 500 g/mol, dermal abosprtion is likely to be limited.

In the absence of substance-specific information, the default dermal absorption value of 50% (not higher than oral absorption) is considered for DNEL derivation.

 

Inhalation

The substance has an estimated vapour pressure of close to 0 Pa at 20°C. Therefore, under normal use and handling conditions, inhalation exposure is not expected. However, the substance may be available for respiratory absorption in the lung after inhalation of aerosols, in the case of spray applications.

In the absence of substance-specific information, the default inhalation absorption value of 100% is considered for DNEL derivation.