Levomenol

Endpoint summary

Description of key information

The LD50 of Candeia Oil after oral administration was found to be > 2000 mg/kg bw for male and female rats (reference 7.2.1 -1). Candeia Oil (source substance), which is a plant extract containing (+/-)-α-Bisabolol as main constituent, is considered to be a suitable read across substance for (-)-α-Bisabolol (target substance). Therefore, it can be assumed that the LD50 of (-)-α-Bisabolol is also > 2000 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The test item is Candeia Oil, which is a plant extract containing α-Bisabolol as main constituent. Studies on acute oral toxicity were not performed for the target substance (-)-α-Bisabolol due to availability of reliable experimental data for Candeia Oil and (+/-)-α-Bisabolol. Candeia Oil and (+/-)-α-Bisabolol are considered to be suitable read across substances.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The source substance Candeia Oil, CAS 515-69-5, which was used in the acute oral toxicity, had a purity of 85.4%. No information on impurities is available. The target substance (-)-α-Bisabolol, CAS 23089-26-1, is a main constituent of the tested Candeia Oil.

3. ANALOGUE APPROACH JUSTIFICATION
Experimental data i.e. acute oral toxicity studies in the rat were available for Candeia Oil and (+/-)-α-Bisabolol. Candeia Oil was tested in an acute oral toxicity study according to OECD 423 in Wistar rats. This study revealed a LD50 of > 2000 mg/kg bw. This result was supported by an acute oral toxicity study with (+/-)-α-Bisabolol in Sprague-Dawley rats. In this study the LD50 was determined to be > 5000 mg/kg bw. The information given on Candeia Oil and (+/-)-α-Bisabolol is considered to be sufficient to cover the required endpoint information for the target substance (-)-α-Bisabolol.

Reason / purpose for cross-reference:

read-across source

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Acute oral toxicity study (reference 7.2.1-1)

A study was performed with Candeia Oil (source substance) according to OECD guideline 423 to assess the acute toxicity following oral administration in Wistar rats. Single doses of 2000 mg/kg bw of test material preparations in olive oil (Ph. Eur./DAB) were given to two dose groups of three fasted animals, each (males and females) by gavage in a sequential manner. No mortality occurred. No clinical signs and findings were observed. The mean body weights of the dose groups increased throughout the study period. No macroscopic pathologic abnormalities were noted in the animals examined at the end of the observation period. Under the conditions of this study the LD50 of the test substance after oral administration was found to be > 2000 mg/kg bw for male and female rats.

Candeia Oil (source substance), which is a plant extract containing (+/-)-α-Bisabolol as main constituent, is considered to be a suitable read across substance for (-)-α-Bisabolol (target substance).

 

Acute oral toxicity study (reference 7.2.1 -2)

A study was performed with (+/-)-α-Bisabolol (source substance) to assess the acute oral toxicity to the rat. The test was performed with 5 male and 5 female rats per dose group. The test substance was formulated in 0.5% aqueous carboxymethyl cellulose formulation with 1 - 2 drops of Cremophor EL, at a dose level of 2150 and 5000 mg/kg bw. After administration a 14 day observation period followed. No mortality occurred. No effects on the body weight were observed. At the highest dose group (5000 mg/kg bw) the animals showed dyspnea, apathy, ruffled fur and a poor general state. The LD50 value was determined to be > 5000 mg/kg bw.

(+/-)-α-Bisabolol (source substance) is considered to be a suitable read across substance for (-)-α-Bisabolol (target substance).

Justification for classification or non-classification

Classification, Labeling, and Packaging Regulation (EC) No 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. Based on this data, the substance is not considered not to be classified for acute oral toxicity under Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EC) No 2017/776.