Fragrance raw materials monographs 275

ACETALDEHYDE E T H Y L cis-3-HEXENYL A C E T A L

Synonyms: (Z)- l -Ethoxy-l-(3-hexenyloxy)ethane; ethyl cis-3-hexenyl acetal; cis-3-hexenyl ethyl acetal. CAS Registry No. 28069-74-1 CAS Index Name: 3-hexene, l-(1-ethoxyethoxy)-, (Z)-

Structure : CH 3 • CH(OCH2 • CH3 )" OCH2" CH2" CH : CH" CH 2 • CH 3 Description: A colourless liquid. Occurrence: Has apparently not been reported to occur in nature. Physical properties:

Refractive index 1.422 Specific gravity 0.851

(Analytical data on the material as tested by RIFM.) Gas chromatogram and infra-red curve on file at R IFM.

Biological data

Acute toxicity. The acute oral LDs0 in rats exceeded 5 g/kg based on 2/10 deaths at that dose and the acute dermal LDs0 in rabbits exceeded 5 g/kg based on 0/10 deaths (Moreno, 1979).

Irritation. As part of an acute dermal LDs0 study, the undiluted material produced moderate oedema and erythema in rabbits patch-tested for 24 hr under occlusion at a dose of 5 g/kg (Moreno, 1979).

A 48-hr closed-patch test at a concentration of 10% in petrolatum on the forearms of 25 volunteers produced no irritation (Kligman, 1978).

Sensitization. A maximizat ion test (Kligman, 1966; Kligman & Epstein, 1975) was carried out on 25 volunteers. The material was tested at a concentration of 10% in petrolatum and produced no sensitization reactions (Kligman, 1978). This test concentration was based on a reported maximum concentration of 1% in consumer products.

References

Kligrnan, A. M. (1966). The identification of contact allergens by human assay. III. The maximization test. A procedure for screening and rating contact sensitizers. J. invest. Derm. 47, 393.

Kligman, A. M. (1978). Report to RIFM, 1 November. Kligrnan, A. M. & Epstein, W. (1975). Updating the maximization test for identifying contact allergens. Contact Dermatitis

I, 231. Moreno, O. M. (1979). Report to RIFM, 22 March.