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

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

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:

3 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Table1: Results from available key study from source substance of the category for toxicity to microorganisms

Name of the substance	CAS	Fatty acids chain length	Type of alcohol	MW	Appareance	Toxicity to microorganisms
Fatty acids, C8-16, 2-ethylhexylesters	135800-37-2	C8-16	2-ethylhexanol	256.42 – 368.65	Liquid	No data
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	Experimental result: EC50(3h) > 100 mg/L (nom.)
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	No data
2-Ethylhexyl stearate	22047-49-0	C18	2-ethylhexanol	396.7	Liquid	No data

 

Based on the category approach and the available study, the EC50 on activated sludge respiration was derived as greater than 100 mg/L (nominal) after 3 hours exposure. The ready biodegradability observed for the category members also demonstrate that these substances show no adverse effects to micro-organisms.

Validity criteria fulfilled:

yes

Conclusions:

Based on the category approach and the available study, the 3h-EC50 to activated sludge respiration was greater than 100 mg/L (nominal).

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.

This category is based on similar chemical properties as long fatty chain (C8 to C18) linked to 2-ethylhexyl esters. The members of the category show the same physico-chemcal properties as a poor solubility in water and a high adsorption potential. Due to this common properties the bioavailability to aquatic microorganisms is expected to be low.

One study was available to assess the toxicity to microorganism. An experimental study was performed according to DIN 38412 method with the Fatty acids, C16-18 C18 unsat CAS 85049-37-2, which is very similar to the target substance. The obtained EC50 value was greater than 100 mg/L (nominal) for 3 hours exposure. Moreover the ready biodegradability observed for the category members also demonstrates that these substances show no adverse effects to micro-organisms.

Based on the category approach and the available study, the 3h-EC50 value for the target substance “Isostearate, 2-ethylhexyl ester” to activated sludge respiration was derived as greater than 100 mg/L (nominal).

Description of key information

Based on the category approach and the available study, the 3h-EC50 to activated sludge respiration was greater than 100 mg/L (nominal).

Key value for chemical safety assessment

EC50 for microorganisms:

100 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 toxicity to micro-organisms

One key study was available to assess the toxicity to microorganism (activated sludge). An experimental study was performed according to DIN 38412 method with the Fatty acids, C16-18, C18 unsatd. CAS 85049-37-2, which is very similar to the target substance. The obtained EC50 value was greater than 100 mg/L (nominal) after 3 hours exposure. Moreover the ready biodegradability observed for the category members also demonstrates that these substances show no adverse effects to micro-organisms.

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.

This category is based on similar chemical properties as long fatty chain (C8 to C18) linked to 2-ethylhexyl esters. The members of the category show the same physical-chemical properties as a poor solubility in water and a high adsorption potential. Due to these common properties the bioavailability to aquatic microorganisms is expected to be low.

The Fatty acids, C16-18, C18 unsatd., which is very similar to the target substance, was tested to determine its toxicity to activated sludge respiration. The obtained EC50 value was greater than 100 mg/L (nominal) for 3 hours exposure. Moreover the ready biodegradability observed for the category members also demonstrates that these substances show no adverse effects to micro-organisms.

Based on the category approach and the available study, the 3h-EC50 value for the target substance “Isostearate, 2-ethylhexyl ester” to activated sludge respiration was derived as greater than 100 mg/L (nominal).