Fragrance raw materials monographs

TERPINYL ISOBUTYRATE

Synonym: p-Menth- l-en-8-yl isobutyrate. CAS Registry No. 7774-65-4 CAS Index Name: propanoic acid, 2-methyl-, l-methyl-l-(4-methyl-3-cyclohexen-l-yl)ethyl ester

409

Structure:

/ - " ' - ' ~ C H 3 CH3 c~---~\ /,---c. ooc.cH

X ~ / C H 3 CHa

Description: A clear liquid. Occurrence: Has apparently not been reported to occur in nature. Preparation: By azeotropic type esterification of terpineol with isobutyric acid (Arctander, 1969). Physical properties:

Refractive index 1.460 Specific gravity 0.934

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

Status

Terpinyl isobutyrate was given GRAS status (No. 3050) by FEMA (1965) and is approved by the FDA for food use (21 CFR 172.515). The Council of Europe (1981) included it in the list of substances that may be added to food without hazard to public health.

Biological data

Acute toxicity. The acute oral LDs0 in rats and the acute dermal LDs0 in rabbits exceeded 5.0 g/kg (Moreno, 1982) with 0/10 deaths at that dose.

Irritation. As part of an acute dermal LDs0 study, the undiluted material produced slight irritant effects in rabbits patch-tested for 24 hr under occlusion at a dose of 5.0 g/kg (Moreno, 1982).

A 48-hr closed-patch test at a concentration of 10% in petrolatum on the backs of 26 volunteers produced no irritation (Epstein, 1982).

Sensitization. A maximization test (Kligman, 1966; Kligman & Epstein, 1975) was carried out on 26 volunteers. The material was tested at a concentration of 10% in petrolatum and produced no sensitization reactions (Epstein, 1982). This test concentration was based on a reported maximum concentration of 1% in consumer products.

References

Arctander, S. (1969). Perfume and Flavor Chemicals (Aroma Chemicals). Vol. 2, no. 2887. S. Arctander, Montclair, NJ. Council of Europe (1981). Flavouring Substances and Natural Sources of Flavourings. Partial Agreement in the Social and

Public Health Field. List 1, no. 300, p. 172. Editeur Maisonneuve S.A., Strasbourg. Epstein, W. L. (1982). Report to RIFM, 27 September. Flavoring Extract Manufacturers' Association (1965). Recent progress in the consideration of flavoring ingredients under

the food additives amendment. 3. GRAS Substances. Fd Technol., Champaign 19 (2), 155. Kligman, 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. Kligrnan, A. M. & Epstein, W. (1975). Updating the maximization test for identifying contact allergens. Contact Dermatitis

1, 231. Moreno, O. M. (1982). Report to RIFM, 29 September.