Registration Dossier

Diss Factsheets

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Key value for chemical safety assessment

Koc at 20 °C:
3 522

Additional information

No experimental adsorption data are available for fatty acids, C16-18 (even numbered), aluminum salts. The substance fatty acids, C16-18 (even numbered), aluminum salts, is produced from natural fatty materials which is a mixture of stearic (C18) and palmitic (C16) acid. The substance consists of up to 90% natural fatty acid and up to 10% of aluminum. Fatty acids, C16-18 (even numbered), aluminum salts are readily biodegradable according to OECD criteria. The fatty acids moiety will completely degrade by the β-oxidation pathway, and therefore no adsorption to soil is expected. Aluminum ions, if released from the test item at all, will be transformed into aluminium hydroxide or will deposit as aluminium oxide in sediment or soil. Both these substances are insoluble under normal environmental conditions in the range of pH 5 – 8. Thus, they precipitate and subsequently are immobilised in soil and sediment. This process nevertheless depends on many factors like pH, alkalinity, temperature, dissolved organic carbon, dissolved inorganic carbon and anion concentration. According to Kaplan (2005) Al Kd values for soil, grout, gravel, clay to be 3700 mL/g and 5000 mL/g for concrete, respectively. Nevertheless, for the completeness of information, in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5, further read-across data from other structurally related substances are provided for the fatty acid component of the test substance: palmitic acid CAS 57-10-3) and stearic acid (CAS 57-11-4). The estimated Koc values for the C16 and C18 components were calculated using the US EPA EPISuite interface using QSAR/QSPR predictions (KOCWIN v2.00).

The estimated Koc values are:

Based on the log Pow method:

C16: Log Koc = 4.1; Koc = 13230 [at 25 ºC]

C18: Log Koc = 4.7; Koc = 51050 [at 25 ºC]

Based on the MCI method:

C16: Log Koc = 3.5; Koc = 3522 [at 25 ºC]

C18: Log Koc = 4.1; Koc = 11700 [at 25 ºC]


Kaplan D.I. (2005) Recommended Distribution Coefficients, Kd Values, for Special Analysis Risk Calculations Related to Waste Disposal and Tank Closure on the Savannah River Site (U), Westinghouse Savannah River Company Savannah River Site.

[LogKoc: 3.5]