Ethyl decanoate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

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: category approach

Justification for type of information:

See "Assessment reports" section 13 or "Categories" section for the justification and rationale document for category approach.

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

growth rate

Table 1: Results from available key studies on the source substances of the category

Common name	CAS	Fatty acid chain length	Type of alcohol	MW	Appareance	Toxicitytoaquaticalgae
Ethyl decanoate	110-38-3	C10	ethanol	200.32	Liquid	No data
Ethyl undecylenate	692-86-4	C11	ethanol	212.33	liquid	No data
Isopropyl laurate	10233-13-3	C12	Isopropanol	242,41	Liquid	no data
Octyl octanoate	2306-88-9	C8	octanol(C8)	256,42	Liquid	no data
Isopropyl myristate	110-27-0	C14	Isopropanol	270,46	Liquid	Experimental result: ErC50(72h) > 0.05 mg/L (meas.Limit of WS)
Dodecanoic hexylester	34316-64-8	C12	Hexanol(C6)	284,49	Liquid	no data
Ethyl linoleate	544-35-4	C18:2	ethanol	308,5	Liquid	no data
Ethyl oleate	111-62-6	C18:1	ethanol	310.52	Liquid	no data
2-ethylhexyl laurate	20292-08-4	C12	2-Ethyl-Hexanol	312,53	Liquid	no data
Fatty acids, coco, 2-ethylhexyl esters	92044-87-6	C12-14	2-ethylhexanol	312.53 – 340.60	liquid	No data

Similar ecotoxicity profile

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

Due to their poor water solubility, these substances are difficult for aquatic testing. If undissolved test material is not properly removed from test vessels, it may cause physical effects, such as decreasing algae growth by increased turbidity of test solutions, or by algae cells getting trapped into oil film or on particles. These effects do not reflect real toxicity of the substances towards the organisms and can be avoided by a step of filtartion.

The algae test performed on Isopropyl myristate showed inhibition when tested on turbid solutions at 100 mg/L, whereas these solutions tested after filtration did not induce any toxicity on algal growth.

The low biodisponibility of the category substances due to their low solubility, can explain their lack of adverse effect to algae.

Conclusion on Target substance

Based on the experimental result obtained, no direct toxicity was expected to aquatic algae from the category substances. The 72h-IC50 for algae of the source substances was considered to be higher than their solubility limits.

Since the limit of water solubility of Ethyl decanoate was estimated to be < 1 mg/L, then the 72h-IC50 to algae of this target substance was defined as > 1 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

Based on the category approach, the 72h-IC50 (growth rate) to freshwater algae of Ethyl decanoate is estimated > 1 mg/L (limit of water solubility).
Hence the target substance was not classified for acute toxicity to aquatic algae according to CLP criteria.

Executive summary:

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A read-across category was performed in order to provide informations on ethyl decanoate CAS 110-38-3.

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.

Based on the experimental data on isopropyl myristate, the category members are expected to show low toxicity to aquatic algae. The 72h-IC50 (growth rate) was defined as higher than 0.05 mg/L, which is the isopropyl myristate limit of solubility.

So when tested up to their limit of solubility, it can be stated that the substances of the category have no adverse effects to the growth of algae.

Since the category members are expected to show the same toxicity level to aquatic organisms due to common structural and physico-chemical properties, the 72h-IC50 (growth rate) to algae of Ethyl decanoate is considered as higher than its solubility limit, which was estimated as < 1 mg/L.

Hence, the target substance was not classified for short-term toxicity to aquatic algae.

Description of key information

Based on the category approach, the target substance ethyl decanoate was considered to have a 72h-IC50(growth rate) higher than 1 mg/L (its limit of water solubility).

According to CLP criteria, no classification is required for ethyl decanoate.

Key value for chemical safety assessment

EC50 for freshwater algae:

1 mg/L

EC10 or NOEC for freshwater algae:

1 mg/L

Additional information

Justification and rationale of the category approach for Ethyl decanoate

This category group covers fatty acid chains linked to alcohols via an ester function. It includes mono-constituent substances and UVCB substances with varying fatty acid chain lengths from C8 to C18-unsaturated and alcohol types (including ethanol, isopropanol, octanol, hexanol and 2-ethylhexanol). This category group was made in order to provide sufficient information for physico-chemical, environmental, ecotoxicological and toxicological characterization of ethyl decanoate (CAS 110-38-3). Some data on the target substance of the category are available.

This category includes:

-       Target substance:

o       Ethyl decanoate (CAS 110-38-3)

-       Source substances:

o       Ethyl undecylenate (CAS 692-86-4)

o       Isopropyl laurate (CAS 10233-13-3)

o       Octyl octanoate (CAS 2306-88-9)

o       Isopropyl myristate (CAS 110-27-0)

o       Dodecanoic hexyl ester (CAS 34316-64-8)

o       Ethyl linoleate (CAS 544-35-4)

o       Ethyl oleate (CAS 111-62-6)

o       2-Ethylhexyl laurate (CAS 20292-08-4)

o       Fatty acids, coco, 2-ethylhexyl esters (CAS 92044-87-6)

Summary of available studies

Isopropyl myristate CAS 110 -27 -0

One reliable and relevant study was performed on isopropyl myristate according to EU Method C.3. Desmodesmus subspicatus was exposed for 72 hours to 100 mg/L (nominal) as emulsion (method 1) and as filtered test solution (method 2) of the test item. Inhibition on the algal growth was observed when the emulsion is tested . No adverse effect related to the test item exposure was observed when the filtrated solutions are tested. Hence, the IC50(growth rate) for green algae during 72 hours exposure period was defined as greater than 0.05 mg/L (limit of water solubility of isopropyl myristate).

Conclusion

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A read-across category was performed in order to provide informations on ethyl decanoate CAS 110-38-3.

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.

Based on the experimental data on isopropyl myristate, the category members are expected to show low toxicity to aquatic algae. The 72h-IC50 (growth rate) was defined as higher than 0.05 mg/L, which is isopropyl myristate limit of solubility.

So when tested up to their limit of solubility, it can be stated that the substances of the category do not have adverse effects to the growth of algae.

Since the category members are expected to show the same toxicity level to aquatic organisms due to common structural and physico-chemical properties, the 72h-IC50 (growth rate) to algae of Ethyl decanoate is considered as higher than its solubility limit, which was estimated as < 1 mg/L.

Hence, the target substance was not classified for short-term toxicity to aquatic algae.