Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Short term toxicity data for invertebrates and algae are available for (Z)-N-Octadec-9-enylhexadecan-1-amide (CAS No. 16260-09-6). 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 (CAS No. 16260-09-6).

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 an analogue substances 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 N-Octadecylstearamide (CAS No. 13276-08-9) to (Z)-N-Octadec-9-enylhexadecan-1-amide (CAS No. 16260-09-6)

The target substance and the source substance are amides of unsaturated or saturated fatty acids, respectively. The target substance, (Z)-N-octadec-9-enylhexadecan-1-amide (oleyl palmitamide, CAS 16260-09-6), and the source substance, N-octadecylstearamide (stearyl stearamide, CAS 13276-08-9), are secondary N-alkyl alkylamides produced from a coupling reaction between an appropriate fatty acid and a fatty amine (March, 1992). It should be noted that the original raw materials used for manufacture of the fatty amines are also similar (or the same) fatty acids.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 (stearyl stearamide, CAS 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.

Key physicochemical parameters and ectoxicological data for the registered and surrogate substances.

Name/CAS #

(Z)-N-Octadec-9-enylhexadecan- 1-amide (CAS No. 16260-09-6)

N-Octadecylstearamide (CAS No. 13276-08-9)

Partition coefficient(log Kow)

Log Kow: > 5.7 at 23°C

Log Kow: 15.51 (QSAR)

Water solubility

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

Water solubility below 1 mg/L. (2.385E-011 mg/L, QSAR)

 

Biodegradability

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 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.

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

Daphnia acute toxicity 48h EC50 mg/L

No toxicity up to the limit of water solubility.

n/a

Long-term toxicity to fish

n/a

n/a

Long-term toxicity to aquatic invertebrates

n/a

n/a

Algae toxicity 72h EC50/NOEC mg/L

No toxicity up to the limit of water solubility.

n/a