Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Justification for grouping of substances and read-across

There are no data available on the aquatic toxicity of Fatty acids, C18-unsaturated, trimers, hydrogenated. In order to fulfil the standard information requirements set out in Annexes VII-IX, in accordance with Annex XI, Section 1.5 of Regulation (EC) No 1907/2006, read-across from structurally similar substances is conducted.

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 and environmental 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 physicochemical, toxicological and ecotoxicological properties may be predicted from data for reference substance(s) by interpolation to other substances on the basis of structural similarity, Fatty acids, C18-unsatd., dimers (CAS No. 61788-89-4), Fatty acids, C18-unsatd., dimers, hydrogenated (CAS No. 68783-41-5), Isooctadecanoic acid (CAS No. 30399-84-9), Fatty acids, C18-unsatd., trimers (CAS No. 68937-90-6) and Fatty acids, C16-18 and C18-unsatd., branched and linear (CAS No. 68955-98-6) are selected as read-across substances for assessment of aquatic toxicity.

The read-across is based on structural similarity as a result of common origin and production process line. Shortly, the source and target substances are derived from catalytically di- and trimerised long-chain fatty acids; dimers and trimers are separated by distillation and unsaturated alkyl chains are hydrogenated as specifically required. A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

Table: Aquatic toxicity of target and source substances

Endpoint

Fatty acids, C18-unsaturated, trimers, hydrogenated (a)

Fatty acids, C18-unsatd., dimers (b)

Fatty acids, C18-unsatd., trimers

Fatty acids, C18-unsatd., dimers, hydrogenated

Fatty acids, C16-18 and C18-unsatd., branched and linear

Isooctadecanoic acid

CAS No.

1373883-45-4

61788-89-4

68937-90-6

68783-41-5

68955-98-6

30399-84-9

Short term toxicity to fish

RA CAS 61788-89-4

RA CAS 68955-98-6

RA CAS 30399-84-9

Experimental result:

LC50 (96h) > 350 mg/L

--

--

Experimental result: LL50 (96 h) >1000 mg/L

Experimental result:

LC50 (48h) = 13.4 mg/L

Long term toxicity to fish

RA CAS 68783-41-5

--

--

Experimental result:

NOEC (28d) ≥ 0.850 mg/L

--

--

Short term toxicity to aquatic invertebrates

RA CAS 68937-90-6

RA CAS 68955-98-6

--

Experimental result:

LL50 (48h) > 1000 mg/L

--

Experimental result:

EL50 (48h) > 1000 mg/L

--

Long term toxicity to invertebrates

waiving

--

--

--

--

--

Toxicity to aquatic algae

RA CAS 68937-90-6

RA CAS 68955-98-6

--

Experimental result:

EC50 (72h) > 1000 mg/L

NOELR (72h) ≥ 1000 mg/L

--

Experimental result:

EL50 (72h) > 1000 mg/L

NOELR (72h) ≥ 1000 mg/L

--

Toxicity to microorganisms

RA CAS 61788-89-4

RA CAS 68955-98-6

RA CAS 30399-84-9

Experimental result: NOELR (16h) ≥ 10000 mg/L

--

--

Experimental result: NOELR (16h) ≥ 10000 mg/L

Experimental result: NOEC (18h) ≥ 4.8 mg/L

(a) The substance subject to the REACh Phase-in registration deadline of 31 May 2013 is indicated in bold font. Only for this substance a full set of experimental results and/or read-across is given.

(b) Reference (read-across) substances are indicated in normal font. Lack of data for a given endpoint is indicated by “--“.

Aquatic toxicity

Short-term aquatic studies for the analogue substances are available for the three trophic levels fish, invertebrates and algae. No mortality occurred up to the limit of water solubility of the test substances with any of the test organisms. In the acute fish toxicity study with Isooctadecanoic acid (CAS No. 30399-84-9), mortality occurred, but at concentrations far above the water solubility of the substance. A solubiliser was used to get a homogeneous dispersion. Therefore, effects at natural conditions are not expected.

The long-term aquatic toxicity of these substances was tested on fish and algae. For both organisms no effects were observed up to the limit of water solubility of the test substance.

In conclusion, based on the data available for its structural analogues, Fatty acids, C18 unsaturated, trimers, hydrogenated is not expected to have acute or chronic effects on aquatic organisms.