Fatty acids, C18-unsatd., esters with triethanolamine

Endpoint summary

Description of key information

The available information suggests that the substance is readily available via the oral route; however absorption via the skin is also possible. This is supported by the physicochemical properties of the substance. If absorbed, the substance may result in accumulation in the adipose tissues. Biliary excretion is considered to be the significant route for the substance.

Key value for chemical safety assessment

Bioaccumulation potential:

low bioaccumulation potential

Additional information

Toxicokinetic Behaviour

The substance is composed as in section 1.2 of IUCLID. It is an amber coloured slightly viscous liquid and the molecular weight of the constituents range from 149.19 - 942.53 g/mol. The low vapour pressure value (2.2 x 10^-3 Pa at 25°C) and predicted negative explosive and oxidising properties shows that the substance is non volatile therefore inhalation is not a significant route of exposure.

The substance has a high log octanol/water partition coefficient value (Log₁₀ Pow -2.48 – 23.1) and low water solubility 1.42 x 10^-5– 6.92 x 10^-5 g/l). The test item is considered not to be a skin sensitiser however mild/moderate dermal irritation was evident therefore skin penetration may be possible. The available acute oral study as well as the repeated dose reproductive screening study did not show any evidence of absorption, metabolism or excretion.

The test item was non-mutagenic in bacteria, non-clastogenic in mammalian cells in vitro and non-mutagenic in mammalian (CHO) cells in vitro in either the absence or presence of an auxiliary metabolising system.

Absorption

The lipophilic nature of the substance (log₁₀ Pow of -2.48 – 23.1) would suggest that the gastro-intestinal tract provides a route of absorption, following oral administration, before entering the circulatory system via the blood. The molecular size of the substance may also allow absorption through passive diffusion. One rate limiting factor is the extreme value for log P_ow which may in fact serve as an inhibitor of significant absorption or reduce the rate of passage.

 

Absorption may also take place via the skin; the lipophilicity of the test item may allow penetration of the dermal membrane. The substance is considered not to be corrosive or a skin sensitizer however there is evidence of dermal irritation.Therefore damage to the skin surface may allow for increased penetration of the substance through the skin.

 

The low vapour pressure value (2.2 x 10^-3 Pa at 25°C) shows that the substance is not available as a vapour therefore inhalation is not a significant route of exposure.

Distribution

Once absorbed, under normal circumstances a high log octanol/water partition coefficient value (Log₁₀P_ow-2.48 - 23.1) would suggest an affinity to accumulate in the adipose tissue, however at extreme values (>10) then this may well not happen.

Metabolism

The results of the repeated dose reproductive screening study did not show evidence to indicate any test item influenced hepatic metabolism. The results of the genotoxicity assays have shown that genotoxicity is neither enhanced or diminished in the presence of the S9 metabolising system.

Excretion

There is no evidence to indicate the route of excretion but poorly water-soluble products are not favourable for urinary excretion and therefore biliary excretion may well be a significant route for this material. Any test item that is not absorbed will be excreted in the faeces.