Concrete of Trigonella foenum graecum L. (Leguminosae) obtained from seeds by extraction with organic solvents

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING:
The substance is a complex mixture, which contains a large number of constituents with different solubility (often low solubility) and volatility. In addition, the composition of this complex substance is mostly unknown and its physical state leads to further difficulties for physico-chemical testing: It is described as visous liquid. Standard tests for partition coefficient endpoint are intended for single substances and are not appropriate for such complex substances.
A study has been conducted in a similar substance according to OECD 117 showing not reliable results (logKow < 0.3 while the substance is mainly not soluble in water).
In addition a feasibility study has been conducted on other natural complex substances in order to define the more suitable standard method to determine the partition coefficient range of such substances. The two first approaches, based on the application of the OECD 117 method, were not applicable due to the very low response of the test item with the HPLC detectors tested (Diode Array Detector and Mass Spectrometry). The third strategy based on the application of the OECD 123 method and the quantification of the test item in both octanol and water phases by a GC-FID analytical method did not allow to detect the totality of the test item constituents.
Finally the application of the conventional Log Pow determination methods is limited due to the limited knowledge of composition of the test item.