[No public or meaningful name is available]

Endpoint summary

Description of key information

The substance Disodium Stearoyl-L-Glutamate is a multi-constituent organic substance composed by disodium hydrogen N-(1-oxooctadecyl)-L-glutamate (main component – up to ca. 63%) and disodium hydrogen N-(1-oxohexadecyl)-L-glutamate (up to ca. 32%), with a molecular weight ranging between 463 and 473.
Based on the organic nature of the components within the substance, complete oral absorption for the substance as a whole might be expected.
In the absence of quantitative information, for the purposes of risk assessment estimation of mammalian dermal absorption is made in accordance with principles adopted by the EFSA guidance on estimating dermal absorption of pesticide active substances (EFSA, 2012).  On this basis, dermal absorption for the substance is assumed at 25%.
In the absence of quantitative information, complete absorption (100%) following inhalation is assumed for the purposes of risk assessment.

Key value for chemical safety assessment

Absorption rate - oral (%):

100

Absorption rate - dermal (%):

25

Absorption rate - inhalation (%):

100

Additional information

The substance is a multi-constituent organic substance composed by disodium hydrogen N-(1-oxooctadecyl)-L-glutamate (main component – up to ca. 63%) and disodium hydrogen N-(1-oxohexadecyl)-L-glutamate (up to ca. 32%), with a molecular weight ranging between 463 and 473. It is an off-white solid powder under ambient conditions, with 76.4% of particles being less than 100 µm in size. It is very soluble in water, in the range of 26.0 to 27.0% w/w or in the range of 350548.35 to 369843.51 mg/L at 20.0 ± 0.5 °C and pH 10.5 to 10.6. It has surfactant properties so that it was not possible to determine an octanol-water partition coefficient. The substance is not readily biodegradable.

 

Absorption

Very little can be inferred from the acute oral toxicity study, because thesigns of systemic toxicity, hunched posture, lethargy and decreased respiratory rate, were noted in a single animal only of the day of dosing.The time of insurgence of these signs, the molecular weight not exceeding 500g/mol, and the good water solubility, all together suggest rapid oral absorption, with absorption starting in the stomach where peptidases are likely to cleave the peptide bond, giving rise to fatty acids and glutamate. In addition,the pH value in the intestinal tract would optimize the water solubility of the substance, and its surface-active properties could enhance intestinal absorption by affecting cell membrane. 

Based on the organic nature of the components within the substance,complete oral absorption for the substance as a whole might be expected. Complete (100%) oral absorption will be used for risk assessment.

 

No adverse effects, either local or systemic, were recorded in an acute dermal toxicity study carried out with a structurally related substance. The skin irritation study used an in-vitro system while the skin sensitisation study conducted with the substance was negative. Nothing can be inferred about the dermal penetration properties of the substance from these studies.

In the absence ofquantitative information, for the purposes of risk assessment estimation of mammalian dermal absorption is made in accordance with principles adopted by the EFSA guidance on estimating dermal absorption of pesticide active substances (EFSA, 2012). On this basis, dermal absorption for the substance is assumed at 25%.

 

In the absence ofquantitative information, complete absorption (100%) following inhalation is assumed for the purposes of risk assessment.

 

Distribution

It can be expected that once absorbed the components of the substance will be widely distributed within the body. It is anticipated that the substance will be metabolised to substrates of endogenous metabolism. The acyl residues will be distributed via chylomicrons, while sodium will become part of the large physiological pool for this electrolyte existing within the body. Glutamic acid will reach the liver, and there subjected to metabolism or re-used for other metabolic processes.

 

Metabolism

The acyl residues and glutamate will be used as a source of energy within the citric acid cycle; in case of glutamate, it will be also used for the synthesis of peptides or other amino acids orexcreted in the form of urea.

 

Elimination

Most of the components deriving from metabolism/degradation of the parent compound will be re-used for other metabolic processes within the body; sodium will be eventually excreted in the urine as will be urea, resulting from the catabolism of glutamate.