Linalyl acetate

Endpoint summary

Description of key information

- Oral:                 Rat LD50 > 9000 mg/kg bw (BASF AG 1969)
- Dermal:            Rabbit: LD50 > 5000 mg/kg bw linalyl acetate (Moreno 1972)
                            Rabbit: LD50 = 5610 mg/kg bw linalool (Fogleman 1970) 

Additional information

There are valid studies available for the assessment of the acute toxicity of linalyl acetate.

 

Oral:

In the key study according to internal BASF protocols, ten male and ten female rats were treated with 200, 1600, 3200, 6400, 8000, 10000 µl/kg bw of linalylacetate (BASF AG, 1969). The animals were observed for 7 days, necropsy was performed with dead animals and with the survivors. The LD50 was >10000 µl/kg bw (eq. to > 9000 mg/kg bw) for male and female rats. No mortality was observed at all doses tested. The following clinical signs of toxicity were observed: Immediately following administration hyperactivity, frequent chewing, elevated breathing, piloerection, salivation, dyspnoea, apathia and agitation were seen. On the following days strubby coat, elevated breathing (6400 µl/kg bw) irregular breathing, crouching (8000-10000 µl/kg bw) and slight apathia (10000 µl/kg bw) were seen. In the high dose groups the animals were without findings on day 2, in the 1600 µl/kg bw dosing group the animals were without findings on day 1, in the 200 µl/kg bw group the animals were without any findings. Nothing abnormal was detected at gross pathology.

Further data on acute oral toxicity in rats or mice were only available as short references from secondary sources. These data provided a LD50 range of 12000 to 14550 mg/kg bw (Jenner 1964, RTECS 1994, Bar 1967), substantiating the absence of an acute oral toxicity potential of linalyl acetate.

 

Inhalation:

In a supportive study, i.e. an standardized inhalation hazard test, 12 rats each were exposed for 8 hours to an atmosphere that had been saturated with the volatile parts of the test compound (vapour) (BASF AG 1969). The test was performed with two different settings concerning the temperature of vapour generation (20°C and 100°C), because at 20°C no significant substance loss was recorded, which means that the enrichment of the air by the volatile parts of the test compound was not detectable. 0/12 rats each died after 8 h exposure at 20°C or at 100°C. At 20°C no symptoms were observed, at 100°C slight mucous membrane irritation and elevated breathing were seen. On day 1 nothing abnormal was detected. At gross necropsy slight bronchitis was seen in animals of the 20°C test. Nothing abnormal was detected there were no necropsy findings in the 100°C test.

No key study is available, however, supportive evidence from an inhalation hazard test does not indicate an acute inhalative toxicity of linalyl acetate, and a study on acute dermal toxicity, covering a relevant route of exposure, is available.

 

Dermal:

In the key study, being available from secondary sources (a peer-reviewed publication), linalyl acetate was administered to three rabbits, the type of coverage was not further specified (Moreno 1972). Observations were made for mortality and toxic effects for a period of 14 days. The LD50 was reported to be >5000 mg/kg bw.

In support, further evidence for the absence of acute dermal toxicity is provided by an acute dermal toxicity study of the metabolically related substance linalool. Groups of 3 albino rabbits per dose were clipped free of hair from the sides and abdomen. The test material was applied and held in close contact with the skin under Saran wrap and bandages for an exposure period of 24 hours at doses of 2500, 5000, 10000 mg/kg bw (Fogleman 1970). The animals were observed daily and sacrificed on day 7. Gross autopsy was carried out on all animals. At 10000 mg/kg bw 3/3 animals died within the first 24 h of the study. Depression and coma was observed. At 5000 mg/kg bw 1/3 animals died. Depression was observed and remained until the 4^thor 5^thday. At termination of the study, body weights were unchanged from the initial weights (no weight gain was observed). At 2500 mg/kg bw no effects were seen. The LD50 was set at 5610 mg/kg bw.

Justification for classification or non-classification

The present data on acute oral and dermal toxicity do not fulfill the criteria laid down in 67/548/EEC and 1272/2008/EEC, and therefore, a non-classification is warranted.