Fatty acids, C14-18 and C18-unsatd., branched and linear, 2-ethylhexyl esters

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Read Across Category

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

reproduction

 Table1: Results from key studies of source chemical of category for long term toxicity to aquatic invertebrates

Name of the substance	CAS	Fatty acids chain length	Type of alcohol	MW	Appareance	Long-term toxicity to aquatic invertebrates
Fatty acids, C8-16, 2-ethylhexyl esters	135800-37-2	C8-16	2-ethylhexanol	256.42 – 368.65	Liquid	Experimental result:NOEC(21d) >= 1 mg/L (nom.,filt.)
Fatty acids, coco, 2-ethylhexyl esters	92044-87-6	C12-14	2-ethylhexanol	312.53 – 340.60	liquid	No data
2-Ethylhexyl palmitate	29806-73-3	C16	2-ethylhexanol	368.65	Liquid	No data
Fatty acids, C16-18 and C18-unsatd., 2-ethylhexyl esters	85049-37-2	C16-18, C18:1	2-ethylhexanol	368.65 – 396.7	Liquid	No data
Fatty acids, C16-18, 2-ethylhexyl esters	91031-48-0	C16-18	2-ethylhexanol	368.65 - 396.7	Liquid	No data
2-Ethylhexyl oleate	26399-02-0	C18:1	2-ethylhexanol	394.67	Liquid	Experimental result:NOEC(21d) >= 1 mg/L (nom.,filt.)
2-Ethylhexyl stearate	22047-49-0	C18	2-ethylhexanol	396.7	Liquid	No data

Similar ecotoxicity profile

Based on the experimental data, the category members have low chronic toxicity to aquatic invertebrates.

The exposure concentrations of aquatic organisms are expected to be low due to the very low water solubility. The combined factors of the lowbiodisponibilityof these substances due to their low water solubility, with their easy and fullmetabolisationcan explain the lack of adverse effects on aquatic invertebrates in short and long- term ecotoxicity tests.

Target substance conclusion

Based on the results obtained on the category members, the 21d-NOEC for Daphnia magna of the target substance "Isostearate2 -ethyl hexyl" was considered >= 1 mg/L  (nominal., filtrated).

Validity criteria fulfilled:

yes

Conclusions:

Based on the category approach and the available studies, the NOEC (No Observed Effect Level) value for 21 days exposure period was defined as ≥ 1.0 mg/L (nominal, filtered).
The target substance was Not Classified for long-term Toxicity to Invertebrates.

Executive summary:

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A Read-Across Category for "Long Chain Fatty Acid, 2-ethylhexyl esters" was performed in order to provide informations on Isostearate 2-Ethylhexyl .

This category was based on common and shared properties as:

-   common functional group,

-   common precursors and the likelihood of common impurities resulting from common process of manufacturing,

-   chemically structurally similar breakdown products obtained via the same biological processes into the organisms, and

-   constant pattern in the changing of the potency of the properties across the category.

Two key chronic studies, considered as relevant and reliable, were performed on Daphnia magna  according to OECD 202 part II , with the Fatty acids, C8-16, 2-ethylhexyl esters (CAS 135800-37-2) and the 2-Ethylhexyl oleate (CAS 26399-49-0). A 21d-NOEC (reproduction) ≥ 1 mg/L (nominal, filtrated) was obtained for these two category members, which attests the low toxicity to aquatic invertebrates already observed in acute tests.  

These key studies covered the fatty acids chain length from C8-16 to C18 unsat. 2-Ethylhexyl esters. Considering the molecular weight and the chain length, a 21d-NOEC (reproduction) on Daphnia magna  ≥ 1 mg/L (nominal, filtrated) can be attributed to the target substance “Isostearate, 2-Ethylhexyl”.

Hence, the target substance was not classified for chronic toxicity to aquatic invertebrates.

Description of key information

Based on the category approach and the available studies, the NOEC (No Observed Effect Level) value for 21 days exposure period to Daphnia magna was defined as ≥ 1.0 mg/L (nominal, filtered).

The target substance was not Classified for long-term toxicity to invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 mg/L

Additional information

Justification and rationale of the category approach for the Isostearate, 2-ethyl hexyl :

This category group covers 2-ethyl hexyl esters linked with fatty acid chains (C8 to C18) unsatured and satured. This category includes monoconstituent substances and UVCB substances varying fatty acid chain length. This category was made in order to provide sufficient information for physicochemical, ecotoxicological and toxicological characterization of the Fatty acids, C14-18 and C18-unsatd., branched and linear, 2-ethylhexyl esters (CAS No 85186-76-1)

The category group includes:

- Fatty acids, C8-16, 2-ethylhexyl esters (CAS No 135800-37-2)

- Fatty acids, coco, 2-ethylhexyl esters (CAS No 92044-87-6)

- 2-Ethyl hexyl palmitate (29806-73-3)

- Fatty acids, C16-18 and C18-unsatd., 2-ethylhexyl esters (CAS No 85049-37-2)

- Fatty acids, C16-18, 2-ethylhexyl esters (CAS No 91031-48-0)

- 2-Ethylhexyl oleate (CAS No 26399-02-0)

- 2-Ethyl hexyl stearate (CAS No 22047-49-0)

Target substance for Category Approach : Fatty acids, C14-18 and C18-unsatd., branched and linear, 2-ethylhexyl esters (CAS No 85186-76-1)

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, environmental fate and ecotoxicity, 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)”. Therefore, the available experimental data were collected and evaluated according to Annex XI requirements.

Summary of available studies on source substances for chronic toxicity to aquatic  invertebrates

Fatty acids, C8-16, 2-ethylhexyl esters CAS 135800-37-2

One key study is available. The long-term toxic effects of Fatty acids, C8-16, 2-ethylhexyl esters on Daphnia magna was conducted according to OECD 202 part II under GLP conditions (Wierich 1998). 1 and 100 mg/L test substance were both tested as WAF test solutions (stirring for 16h to 7 days, settling for 2 hours, filtration through a glass fiber filter). In the solution of 1 mg/L no effects on Daphnia magna were observed for mortality and reproduction. On the other hand, in the solution of 100 mg/L a significant reduction of the reproduction was stated. The authors supposed that the effects in the 100 mg/L filtered test solution are due to a better water soluble by-compound (for example a short chain fatty acid ester) or - less likely due to a toxic impurity. Therefore, a 21d-NOEC( reproduction) ≥ 1 mg/L (nominal, filtrated) was given.

2-Ethylhexyl oleate CAS No 26399-02-0

The available study investigated the long-term effects of 2-ethylhexyl oleate (CAS 26399 -02 -0) to the freshwater invertebrate Daphnia magna (Kuech 1995). The study was performed according to the OECD guideline 202, part 2 under GLP conditions. Test concentrations of nominal 1 and 100 mg/L were prepared (stirring for 16h to 5 days) and then filtered to give the test solutions. Analytically, concentrations of <0.01 mg/L were retrieved from both nominal concentrations and corresponds to the limit of solubility of the tested substance.

Effects to Daphnia magna were observed during  21 days with no adverse effect at 1 mg/l and 90% mortality (on day 19) at 100 mg/L. 23% reduction of reproduction (number of offspring) in the 100 mg/L sample occurred after 21 days, with no effect in the 1 mg/L sample resulting in a 21d-NOEC(reproduction) ≥ 1 mg/L (nominal, filtered). However if the reproduction up to day 17 in the 100 mg/L sample was compared to the reproduction in the control, no reduction of reproduction was stated. So the effect on the reproduction for the highest concentration  is due to the mortality of the parent animals which happens suddenly on day 19.  The authors stated, that the deaths observed with the highest concentration could be attributed to sample contamination. A  21d-NOEC(mortality) ≥ 1 mg/L (nominal, filtered) was reported.

Conclusion on the target substance

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A Read-Across Category for "Long Chain Fatty Acid, 2-ethylhexyl esters" was performed in order to provide informations on Isostearate 2-Ethylhexyl .

This category was based on common and shared properties as:

-   common functional group,

-   common precursors and the likelihood of common impurities resulting from common process of manufacturing,

-   chemically structurally similar breakdown products obtained via the same biological processes into the organisms, and

-   constant pattern in the changing of the potency of the properties across the category.

Two key chronic studies, considered as relevant and reliable, were performed on Daphnia magna  according to OECD 202 part II , with the Fatty acids, C8-16, 2-ethylhexyl esters (CAS 135800-37-2) and the 2-Ethylhexyl oleate (CAS 26399-49-0). A 21d-NOEC (reproduction) ≥ 1 mg/L (nominal, filtrated) was obtained for these two category members, which attests the low toxicity to aquatic invertebrates already observed in acute tests.  

These key studies covered the fatty acids chain length from C8-16 to C18 unsat. 2-Ethylhexyl esters. Considering the molecular weight and the chain length, a 21d-NOEC (reproduction) on Daphnia magna  ≥ 1 mg/L (nominal, filtrated) can be attributed to the target substance “Isostearate, 2-Ethylhexyl”.

Hence, the target substance was not classified for chronic toxicity to aquatic invertebrates.