Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

No data are available on the toxicity of (Z)-N-octadecyldocos-13-enamide (CAS No. 10094-45-8) to fish, daphnia and algae.

Justification for analogue approach of substances and read-across

In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met. In particular for human toxicity, information shall be generated whenever possible by means other than vertebrate animal tests", which includes the use of information from structurally related substances (grouping or read-across).

Having regard to the general rules for grouping of substances and read-across approach laid down in Annex XI, Item 1.5, of Regulation (EC) No 1907/2006, whereby substances may be considered as analogue approach provided that their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity, the substances listed below are structural similar related secondary fatty amides. In particular, for each specific endpoint the source substance(s) structurally closest to the target substance is chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across.

A detailed justification for analogue approach of chemicals and read-across is provided in the technical dossier (see IUCLID Section 13).

Read-across from stearyl stearamide (CAS No. 13276-08-9) to (Z)-N-octadecyldocos-13-enamide (CAS No. 10094-45-8):

The target substance, (Z)-N-octadecyldocos-13-enamide (stearyl erucamide, CAS 10094-45-8) and the source substances, N-octadecylstearamide (stearyl stearamide, CAS 13276-08-9) and (Z)-N-octadec-9-enylhexadecan-1-amide (oleyl palmitamide, CAS 16260-09-6), are secondary amides which belong to the chemical class of N-Fatty Alkyl Amides of Saturated and Unsaturated Fatty Acids. The first source substance, (Z)-N-octadec-9-enylhexadecan-1-amide (oleyl palmitamide, CAS 16260-09-6), is a monoconstituent substance containing the oleyl amide of palmitic acid. Palmitic acid is a saturated fatty acid with a linear carbon chain consisting of predominantly 16 carbon atoms and is more correctly called hexadecanoic acid. Oleylamine (CAS 112-90-3) is a derivative of oleic acid, being a primary amine with a mono-unsaturated fatty alkyl group with a carbon chain consisting of 18 carbon atoms and with a double bond at position 9 of the carbon chain, and is more correctly called (Z)-octadec-9-en-1-amine.

The second source substance, N-octadecylstearamide (stearyl stearamide, CAS 13276-08-9) is a monoconstituent substance containing predominantly the stearyl amide of stearic acid. Commercial stearic acid contains both stearic and palmitic acid components but in this case the palmitic acid component is <20%. In the fatty acid nomenclature, these fatty acids are denoted C18 (stearic) and C16 (palmitic), respectively, in accordance with the length of their carbon chains.

For the following endpoints, data from the related substance N-octadecylstearamide (stearyl stearamide, CAS 13276-08-9) will be used as read-across:

The short-term toxicity of N-octadecylstearamide (CAS No. 13276-08-9) to fish was investigated in one study according to EU Method C.1 and following GLP principles (Balk, 1989). In this limit test, guppies (Poecilia reticulata) were exposed to a nominal concentration of 1000 mg/L under semi-static conditions.

For the following endpoints, data from the related substance (Z)-N-octadec-9-enylhexadecan-1-amide (CAS No. 16260-09-6) will be used as read-across:

Short term toxicity data for invertebrates and algae are available for (Z)-N-octadec-9-enylhexadecan-1-amide. The test substance is highly insoluble in water and no effects were observed to aquatic algae and daphnia in the range of water solubility of (Z)-N-octadec-9-enylhexadecan-1-amide. The toxicity of (Z)-N-octadec-9-enylhexadecan-1-amide to aquatic microorganisms was investigated in a respiration inhibition test according to OECD guideline 209. No effects of the test item were demonstrated and an EC50 (3 h) > 1000 mg/L and a NOEC ≥ 1000 mg/L were determined.

Key physicochemical parameters and ecotoxicological data for the registered and read across substances.

Name/CAS #

(Z)-N-Octadecyldocos-13 -enamide/Stearyl erucamide/10094-45-8

(Z)-N-Octadec-9 -enylhexadecan-1 -amide/Oleyl palmitamide/16260-09-6

N-octadecylstearamide/13276 -08 -9

Partition coefficient(log Kow)

Log Kow: > 5.7 at 23°C

Log Kow: > 5.7 at 23°C

Log Kow: 15.51 (QSAR)

Water solubility

WoE: Water solubility < 0.01 mg/L at 20°C

Water solubility < 0.01 mg/L at 20°C and pH 6.6

Water solubility < 0.01 mg/L. (2.385E-011 mg/L, QSAR)

Biodegradability

RA from stearyl stearamide: Not readily biodegradable: 8-24 % after 28 days

Not readily biodegradable: 42% (ThO2) after 30 days (OECD 301 D) and 27% (ThO2) after 42 days (DGXI/400/84)

Not readily biodegradable: 8-24 % after 28 days

Bioaccumulation

Low bioaccumulation potential (BCF = 0.89 - 3.16 L/kg wet-wt, QSAR)

Low bioaccumulation potential (BCF = 0.89 L/kg wet-wt, QSAR)

Low bioaccumulation potential (BCF = 3.16 L/kg wet-wt, QSAR)

Fish acute toxicity 96h LC50 mg/L

RA from stearyl stearamide: LC50 (96 h) > 1000 mg/L. No toxicity up to the limit of water solubility.

RA from stearyl stearamide: LC50 (96 h) > 1000 mg/L. No toxicity up to the limit of water solubility.

LC50 (96 h) > 1000 mg/L. No toxicity up to the limit of water solubility.

Daphnia acute toxicity 48h EC50 mg/L

RA from oleyl palmitamide: No toxicity up to the limit of water solubility.

No toxicity up to the limit of water solubility.

n/a

Long-term toxicity to fish

n/a

n/a

n/a

Long-term toxicity to aquatic invertebrates

n/a

n/a

n/a

Algae toxicity 72h EC50/NOEC mg/L

RA fromoleyl palmitamide: No toxicity up to the limit of water solubility.

No toxicity up to the limit of water solubility.

n/a