(undec-10-enoylamino)acetic acid

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Effects on fertility

Description of key information

Summarizing read-across to undecylenoyl glycine, it is possible to predict the toxicity profile of target substance based on the source substances capryloyl glycine and undecylenic acid (See document "Prediction of reproductive toxicity for undecylenoyl glycine using read-across approach").

A well conducted study OECD test n°422 is available on Capryloyl glycine (source substance) and gave a NOAEL for parental toxicity of 200 mg/kg/day, a NOEL for reproductive performance (mating and fertility) of 200 mg/kg/day and NOEL for toxic effects on progeny of 200 mg/kg/day (highest dose tested).

Furthermore, a Reproduction/ Developmental Toxicity Screening Test (OECD 421) is available on the source substance undecylenic acid and was also considered robust scientifically. Under the experimental conditions of this study, NOAEL value for parental toxicity was considered to be 150 mg/kg/day, NOEL for reproductive performance (mating and fertility) was considered to be 450 mg/kg/day. There was no substance induced effect on male and female reproductive performance, or on the progeny at any dose level.

Moreover, the administration of undecylenoyl glycine by oral route during 28 days in rats did not show any effect on the sexual organs. 

Toxicity to reproduction of target substance undecylenoyl glycine based on read-across can be predicted as follows:
- NOAEL for parental toxicity = 150 mg/kg
- NOAEL for reproductive performance = 200 mg/kg

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Justification for type of information:

In accordance with EC Regulation No. 1907/2006, Annex XI, 1.5 to REACH regulations ‘Read-across and grouping of substance’. Toxicity to reproduction was evaluated for the target substance- undecylenoyl glycine (CAS No. 54301-26-7), considering capryloyl glycine (CAS
No. 14246-53-8) and undecylenic acid (CAS No. 112-38-9) as source substances. Read across was performed as per scenario 1 of read-across assessment framework (RAAF) for both the
source substances based on the hypothesis that different substances give rise to similar or
common compounds to which the organism is exposed. The hypothesis for both the source
substances is briefly explained and discussed in detail in the report entitled "Prediction of reproductive toxicity for undecylenoyl glycine using read-across approach" (See Attached justification")

Reason / purpose for cross-reference:

read-across source

Principles of method if other than guideline:

Toxicity to reproduction was evaluated for the target substance- undecylenoyl glycine (CAS No. 54301-26-7), considering the reproductive toxicity of 2 source substances: capryloyl glycine (CAS No. 14246-53-8) and undecylenic acid (CAS No. 112-38-9)

Species:

rat

Route of administration:

oral: gavage

Duration of treatment / exposure:

between 30 and 54 days

Key result

Dose descriptor:

NOAEL

Effect level:

150 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other:

Remarks on result:

other: all the parameters were assessed in the supporting studies

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 200 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: all the parameters were assessed in the supporting studies

Key result

Reproductive effects observed:

no

Conclusions:

Summarizing read-across to undecylenoyl glycine, it is possible to predict the toxicity profile
of target substance based on the source substances capryloyl glycine and undecylenic acid.
Reproductive toxicity for target substance undecylenoyl glycine based on read-across can be
predicted as follows:
- NOAEL for parental toxicity = 150 mg/kg
- NOAEL for reproductive performance = 200 mg/kg

Executive summary:

In accordance with EC Regulation No. 1907/2006, Annex XI, 1.5 to REACH regulations ‘Read-across and grouping of substance’. Toxicity to reproduction was evaluated for the target substance undecylenoyl glycine (CAS No. 54301-26-7), considering capryloyl glycine (CAS No. 14246-53-8) and undecylenic acid (CAS No. 112-38-9) as source substances. Read across was performed as per scenario 1 of read-across assessment framework (RAAF) based on the hypothesis that different substances give rise to similar or common compounds to which the organism is exposed. 

The amino acid alkyl amides are reported to be synthesized by acylation of amino acids with fatty acids or fatty acid chlorides. Compounds of this class share common metabolic pathways where parent molecule get metabolized to amino acid and fatty acid by the action of enzyme amidase. Rationale using Scenario 1 for read-across hypothesis is based on common and shared properties between source and target molecule as:
i. Structurally similar compounds with common mechanism of action linking the possibility of similar qualitative and quantitative effects.
ii. Exposure to other compounds by bio-transformation of parent molecule to similar metabolites i.e. formation of common and non-common compound on bio-transformation.

Bio-transformation of source and target substance will lead to generation of glycine as common metabolite while caprylic acid and undecylenic acid will be produced as non-common compounds by capryloyl glycine and undecylenoyl glycine, respectively. This conclusion justifies the use of analogue approach scenario 1 to gather necessary information required for data gap filling using capryloyl glycine as the source substance. 

Structural similarity and differences between source and target substances, toxicity of glycine (common compound) and the consequences of the formation of non common compounds were discussed in the document "Prediction of reproductive toxicity for undecylenoyl glycine using read-across approach" (see attached justification). Furthermore, toxicity to reproduction data of undecylenic acid was taken into account to reinforce the prediction. 

- NOAEL for parental toxicity = 150 mg/kg
- NOAEL for reproductive performance = 200 mg/kg

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

200 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

prediction based on two well conducted studies

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on data available on the source substances and findings of the subacute toxicity study (OECD 407) available with the target sustance, it can be concluded that undecylenoyl glycine does not affect reproductive performance and fertility and is not classified according to the GHS.