|IDENTIFICATION AND USE: Linalool is a colorless liquid with a spicy herbal odor. It is used as fragrance component in perfumes, cosmetics, soaps, and detergents; flavoring agent in foods. It is also used as a synthetic intermediate. It is registered for pesticide use in the U.S. but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses.
HUMAN EXPOSURE AND TOXICITY: Linalool at concentrations up to 20% was consistently found not to be a sensitizer in human maximization tests. It was not phototoxic or photoallergenic in human tests. Linalool can cause allergic contact dermatitis. Linalool was not genotoxic when tested in vitro by the micronucleus test on peripheral human lymphocytes.
ANIMAL STUDIES: Linalool was irritating to rabbit skin. Series of Draize tests with fragrance materials indicated that linalool was not a sensitizer in guinea pigs. Repeated application on sheep skin caused signs comparable to acanthosis. Rats were admin linalool 1500 mg/kg/day by gavage for 5 days. Absolute and relative liver weights were increased in treated animals; microsomal protein content was decreased. Psychopharmacological evaluation of linalool in vivo in rats showed that it has marked dose-dependent sedative effects on the central nervous system, including hypnotic, anticonvulsant and hypothermic properties. The study reports an inhibitory effect of linalool on glutamate binding in the rat cortex. In cats signs of toxicosis include hypersalivation, muscle tremors, ataxia, depression, and hypothermia. The sedative properties of linalool were investigated in mice. The significant decrease in the motility of female and male laboratory animals under standardized experimental conditions is found to be closely dependent on the exposure time. 10/sex/treatment rats received daily oral doses of 160, 400 or 1000 mg/kg bw linalool during 28 days. One male and one female of the high dose group were found dead. From a 28-day subchronic toxicity study with the essential oil of coriander with 72.9% linalool and 22.3% other identified terpenoids no remarkable effects on the primary reproductive organs in both females (ovaries and uteri) and males (testes and epididymides) was noted in any animal from any dosage group up to 1000 mg/kg bw/day, both macroscopically at dissection and also microscopically during histopathology of every (10 male, 10 female) high-dose animal. The genotoxic potential of linalool has been evaluated for mutagenicity in bacteria and in cultured mouse L5718Y tk+/. cells, and by cytogenicity in Chinese hamster ovary (CHO) cells via SCE, a chromosome aberration study, and an in vivo micronucleus test. The mutagenicity and clastogenicity data are sufficient to indicate that linalool is not genotoxic.
ECOTOXICITY STUDIES: For linalool, LC50 > 28.8 ppm for Rainbow Trout, a LC50 of 36.8 ppm for Bluegill, and a LC50 of 36.7ppm for aquatic invertebrates.