Fatty acids, C16-18, zinc salts

Endpoint summary

Description of key information

- Appearance: white, odourless solid

- Melting point: 121 °C

- Decomposition: approx. 330 °C before boiling, no boiling point could be determined

- Relative density: 1.11 at 20 °C

-Granulometry of a representative test material is summarized as follows: D10 = 4.52 µm, D50 = 27.43 µm, D90 = 78.37 µm

- Surface tension: 64.56 mN/m +/- 0.05 mN/m (90 % saturated aqueous solution)

- Water solubility: 0.03 to 0.18 mg/L dissolved zinc depending on test conditions

- Transformation/dissolution: at pH 8 in modified ISO 6341 media: Loading 1 mg/L: 19 µg Zn/L (7 days), 29 µg Zn/L (28 days); Loading 10 mg/L: 90 µg Zn/L (7 days); Loading 100 mg/L: 369 µg Zn/L (7 days)

- Flammability: not flammable.

Vapour pressure, partition coefficient, flash point, explosive properties, self-ignition temperature, oxidising properties, stability in organic solvents and identity of relevant degradation products as well as dissociation constant and viscosity are not relevant for this substance in accordance with column 2 of the respective sections of Regulation (EC) No 1907/2006, Annexes VII to IX and other justifications.

Additional information

Fatty acids, C16-18, zinc salts is a white, odourless solid with a melting point of 121 °C. As the substance started decomposing at approximately 330 °C before boiling, no boiling point could be determined. The relative density of Fatty acids, C16-18, zinc salts is 1.11 at 20 °C. As the substance is a salt with a melting point of 121 °C, vapour pressure can be safely assumed to be negligible, i. e. below the level of relevance (10^-5 Pa). The surface tension of a 90 % saturated aqueous solution of Fatty acids, C16-18, zinc salts was determined to be 64.56 mN/m (standard deviation 0.05 mN/m). Due to the fact that the surface tension is > 60 mN/m, the test item is classified as not surface-active substance. The solubility of Fatty acids, C16 -18, zinc salts resulted in 0.03 to 0.18 mg/L dissolved zinc depending on test conditions. Transformation/dissolution of Fatty acids, C16 -18, zinc salts at pH 8 (the pH that maximises dissolution) resulted in the following dissolved zinc concentrations in modified ISO 6341 media:

Loading 1 mg/L:

-after 7 days: 19 µg Zn/L

-after 28 days: 29 µg Zn/L

Loading 10 mg/L:

-after 7 days: 90 µg Zn/L

Loading 100 mg/L:

-after 7 days: 369 µg Zn/L

The partition coefficient of this substance is not considered to be relevant.

Fatty acids, C16-18, zinc salts is not flammable.

Flash point, explosive properties, self-ignition temperature, oxidising properties, stability in organic solvents and identity of relevant degradation products as well as dissociation constant and viscosity are not relevant for this substance in accordance with column 2 of the respective sections of Regulation (EC) No 1907/2006, Annexes VII to IX and other justificatons.

The granulometry of a representative test material is summarized as follows:

D10 = 4.52 µm

D50 = 27.43 µm

D90 = 78.37 µm

 

Justification for classification or non classification

Fatty acids, C16-18, zinc salts does not need to be classified for physico-chemical properties, according to CLP Regulation (EC) No 1272/2008 and its subsequent amendments. Fatty acids, C16-18, zinc salts is not flammable,explosive properties are considered non-relevant for Fatty acids, C16-18, zinc salts based on lack of functional groups and oxidizing properties are considered non-relevant based on the chemical structure of the substance. In the long experience with substance, Fatty acids, C16-18, zinc salts, no indications on metal corrosivity became evident.

This conclusion on non classification is in line to conclusion from EU RAR “Zinc stearate (CAS# 91051-01-3, CAS# 557-05-1) Part I - Environment (Final report R074_0805_env, May 2008):

“Data on boiling point, vapour pressure, and surface tension were not provided. In view of the nature of the substance determination of these parameters is considered to be irrelevant. Information on flammability, explosive properties and oxidizing properties is not available. However, on theoretical considerations the compound is concluded to be not flammable, not explosive and not oxidizing."