Toxicity of terpenes

In Vivo Efficacy and Dermal Toxicity of Terpenes Used... 

The toxicity of terpene alcohols when used as fragrance ingredients has been intensively reviewed [77]. At concentrations likely to be encountered by consumers, these chemicals are considered nonirritating to human skin. At the present maximum use concentrations, their potential for eye irritation is considered minimal. 6,7-Dihydroxy geraniol is a potent skin sensitizer and has been prohibited in fragrance materials. Linalool may contain impurities or oxidation products that are strong sensitizers. Famesol is a weak sensitizer so that its use in fragrance materials has been restricted [77]. 

The great diversity of terpenes helps to cormteract tolerance by herbivores. In all, terpenes are not very toxic to vertebrates. Many mammals ingest a significant amount of terpenoids with their diet. Monoterpenes from pine oil added to the diet reduces food intake in red deer, Cervuselaphus, calves (Elliot and Loudon, 1987). The brush-tailed possmn, Trichosurus vulpecula, detoxifies (-l-)-a-pinene to alcohol and carboxylic acid derivatives. 

In all three studies, but particularly In the 2 dealing with resistance-susceptibility characteristics of foliage quality, specifically the higher quantities of terpenes were correlated with reduced budworm success. At any particular site all of the trees sampled contained the same basic complement of terpenes, albeit, some were present In low quantities. The effect, which we assume Is one of toxicity, of the terpenes In reducing budworm success, then, was due to an Increase In their quantitative amounts. In other words, the terpenes were acting In a quantitative or dosage dependent fashion. 

The complex Interactions of terpenes with insect growth and reproduction and with the Insects ability to metabolise potentially toxic, lipophilic foreign compounds will be discussed briefly in the following. 

Mammalian PLANT RESISTANCE TO INSECTS Table I acute toxicities of plant terpenes ... 

The biological activity and toxicity of terpenoids to herbivores has been discussed (56,84) and representatives of each major type of terpene are known to be active. Well known examples are sesquiterpene lactones, pyrethrins, and several classes of diter-penes and triterpenes. 

Toxic gases and vapors (such as carbon monoxide and the partial oxidation products of terpenes) may be released in a fire involving turpentine. Turpentine attacks some coatings and some forms of plastic and rubber. 

Fragrance products (cologne and toilet water) containing mixtures of aldehydes, esters, terpenes, and carboxylic acids were found to induce acute respiratory and neurotoxic effects in laboratory animals. These effects were not predicted from a consideration of the toxicities of the individual chemicals in the amounts present. ... 

Some volatile products accumulate at significant levels only at specific stages in the life cycles of microorganisms. This may be due in part to toxicity of metabolites which, when they reach threshold levels in the culture media, inhibit the organism. For example, Schindler and Bruns 51) found that Ceratocvstis variospora is inhibited by higher concentrations of its own terpene metabolites. They were able to significantly improve yields of these products by trapping the end products on resins. 

Chenopodium abrosioides is endemic to South America, but it has been introduced to Central and North America, to Europe and to Africa. Chenopodium anthelminticum is a variety thereof, and there are a number of further varieties, differing in their contents of terpenes. The botanical classification has still to be revised. Toxic parts include the fresh blooming... 

While strong evidence is lacking and difficult to obtain, many if not all of the aforementioned halogenated metabolites are likely produced as defensive environmental adaptations. Just as chlorine substitution increases the potency of commercial pesticides, the toxicity of simple terpenes is greatly increased by virtue of added bromine substituents. Those marine organisms that produce substances of this nature cleeirly benefit by enhanced survival against potential predators. 

Knowledge of the spectrum of insecticidal activity is limited for most of the terpenoids. The results of d-limonene trials against a wide range of insect groups indicate that this important constituent of citrus oil is toxic to some life stages of some species via some routes of exposure (4,5,6,2) Its utility as a broad-spectrum insecticide, however, does not seem feasible. Spectrum of repellent activity has been evaluated for several types of terpenes, and reproductive effects have been described for some chemicals (1,8). 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of CO, CO2 emits toxic fumes underfire conditions NFPA Health 0, Reactivity 0 Storage Store in cool, dry place keep tightly closed keep away from oxidizing materials Uses Intermediate in mfg. of terpene alcohols fragrance in cosmetics Manuf./Distrib. Doingcom http //www.doingcom.com, Fluka http //www.sigma-aldrich. com... 

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