ETHYL 2-METHYL-4-PENTANOATEETH OXANOATE-369 CRUDE

Endpoint summary

Description of key information

Acute oral toxicity: LD50 >5000 mg/kg bw for Eth Oxanoate 369 Crude based on read across from Ethyl 2-methyl-3-pentenoate, which was tested in a study similar to OECD TG 401

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

5 000 mg/kg bw

Additional information

The executive summary of the acute oral toxicty study (OECD TG 401) performed with the major constituent, Ethyl-2‐methylpent‐3‐enoate, is presented and thereafter the read across justification.

Acute oral toxicity

The acute oral toxicity has been studied in a similar to OECD TG 401 test. The substance was administered at a dose of 5000 mg/kg bw to 5 male and 5 female SD rats and animals were observed for 14 days. No mortality and no clinical signs were observed. There were no treatment related necropsy findings. There were no adverse effects on body weight gain in animals of either sex except for one female losing 5 grams of weight between day 7 and 14. The acute oral toxicity (LD50) was determined to be >5000 mg/kg.

Acute oral toxicity of Eth Oxanoate 369 Crude based on read-across from its major constituent Ethyl-2-methyl-3-pentenoate (CAS# 58625-89-1)

Introduction and hypothesis for the analogue approach

The multi-constituent substance Eth Oxanoate 369 Crude consists of two main constituents: 62% Ethyl-2-methyl-3-pentenoate (CAS# 58625-89-1) and 32% Ethyl-2‐methylpentanoate (CAS# 39255-32-8). For Eth Oxanoate 369 Crude, no experimental acute oral toxicity data are available. In accordance with Article 13 of REACH, lacking information can be generated by means other than experimental testing, i.e. applying alternative methods such as, QSARs, grouping and read-across. For assessing the acute oral toxicity potential of Eth Oxanoate 369 Crude, the analogue approach is selected because for one of the constituents, Ethyl-2-methyl-3-pentenoate, reliable acute oral toxicity information are available which can be used for read-across.

Hypothesis: Eth Oxanoate 369 Crude has the same acute oral toxicity potential as Ethyl-2-methyl-3-pentenoate, because the latter substance is its main constituent and the other constituent is similar in chemical structure, kinetics and reactivity.

Available information: For the major constituent (Ethyl-2‐methylpent‐3‐enoate), an acute oral toxicity study is available (OECD TG 401), showing LD50 > 5000 mg/kg bw.

Target chemical and source chemical

Chemical structures of the target chemical and the source chemical are shown in the data matrix, including physico-chemical properties.

Purity / Impurities

The major and minor constituents of Eth Oxanoate 369 Crude are presented in the Data matrix. Impurities are < 10%.

Analogue approach justification

According to Annex XI 1.5, read-across can be used to replace testing when the similarity can be based on a common backbone and a common functional group. When using read-across the result derived should be applicable for C&L and/or risk assessment and it should be presented with adequate and reliable documentation, which is presented below.

Analogue selection: For Eth Oxanoate 369 Crude, the analogue and constituent Ethyl-2-methyl-3-pentenoate was selected as source chemical for read-across because it is the major constituent (62%) of Eth Oxanoate 369 Crude and experimental acute oral toxicity data is available.

Structural similarities and differences: The major constituent, Ethyl-2-methyl-3-has a molecular weight of 142 g/mol and has a similar structure to the minor constituent (32%), Ethyl-2‐methylpentanoate, which has a molecular weight of 144 g/mol. The only difference in their structures is that Ethyl-2-methyl-3-pentenoate has a double bond on carbon 3 of the pentene ester.

Toxico-kinetics, absorption: The bioavailability of the constituents of Eth Oxanoate 369 Crude and Ethyl-2-methyl-3-pentenoate are expected to have similar absorption via all routes based on the similarity in chemical structure and physico-chemical properties. The molecular weights, water solubility and log Kow values of Eth Oxanoate 369 Crude and Ethyl-2-methyl-3-pentenoate are favourable for uptake.

Toxico-dynamics: Eth Oxanoate 369 Crude’s constituents have the ester as a functional group. These similar constituents present in Eth Oxanoate 369 Crude and Ethyl-2-methyl-3-pentenoate will present similar reactivity and therefore similar acute oral toxicity.

Uncertainty of the prediction: There are no uncertainties other than those already addressed above. For the minor constituent an LC50 of >2000 mg/kg bw is found on the ECHA dissemination site further supporting the absence of acute oral toxicity for Eth Oxanoate 369 Crude (https://echa.europa.eu/nl/registration-dossier/-/registered-dossier/10528).

Data matrix

The relevant information on physico-chemical properties and toxicological characteristics are presented in the data matrix below.

Conclusions on acute oral toxicity for hazard and risk assessment

For Eth Oxanoate 369 Crude no acute oral toxicity data is available. Ethyl-2-methyl-3-pentenoate information can be used for read-across is used to fill this data gap. When using read-across, the result derived should be applicable for C&L and/or risk assessment, and should be presented with adequate and reliable documentation. This documentation is presented in the current text. For the constituent and analogue Ethyl-2-methyl-3-pentenoate, a well conducted acute oral toxicity test with a LD50 of > 5000 mg/kg bw is available. This information can be used for read-across to Eth Oxanoate 369 Crude.

Final conclusion: For Eth Oxanoate 369 Crude the oral LD50 is >5000 mg/kg bw.

Data matrix to support the read-across to Eth Oxanoate 369 Crude from Ethyl-2-methyl-3-pentenoate for acute oral toxicity

Endpoint	Eth Oxanoate 369 Crude	Ethyl-2-methyl-3-pentenoate	Ethyl-2‐methylpentanoate
	Target	Major constituent Source	Minor constituent
Chemical structure
CAS number	Not applicable	58625-89-1	39255-32-8
EC number	952-991-2	854-058-4	254-384-1
Typical conc. (%)	Not applicable	62	32
REACH registered	-	registered	registered
Empirical formula	Not applicable	C8H14O2	C8H16O2
Molecular weight	142 – 144	142	144
Phys-chem
Log Kow	3.0 (measured major constituent)*	2.54 (EPISUITE) 3.1 (measured)*	2.76 (EPISUITE) 2.09 (ECHA dissemination site,)
Water Solubility (mg/L)	612.3 (measured, major constituent)	612.3 (measured)	467(ECHA dissemination site)
Human health endpoints
Acute oral toxicity	Read across from major constituent	LD50 >5000 mg/kg bw (OECD 401)	LD50 >2000 mg/kg bw (ECHA dissemination site)

*this is the same substance, measured twice with a log Kow of 0.1 difference

Justification for classification or non-classification

The substance does not have to be classified for acute oral toxicity according to EU CLP (EC No. 1272/2008 and its amendments).