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No key study is avaliable for the assessment of the toxicokinetics, metabolism and distribution of 3,7-dimethyloct-6-enenitrile.

Based on its physicochemical properties, i.e. small molecular weight, moderate LogPow, and moderate water solubility at room temperature (Log Kow = 3.1; MW=151.24, Water solubility =119 mg/L), 3,7-dimethyloct-6-enenitrile is considered to become readily bioavailable via the dermal and oral route. In acute oral toxicity studies in rats and mice, administration of 3,7-dimethyloct-6-enenitrile resulted in systemic toxicity including mortality and systemic effects have been observed after repeated oral dosing, providing evidence for relevant oral absorption. On the basis of the low vapour pressure at room temperature (Vapour pressure=4.81 Pa), the exposure via inalation of 3,7-dimethyloct-6-enenitrile as a vapour is low.

Two studies reported in literature are available providing information on the metabilization and elimination of 3,7-dimethyloct-6-enenitrile. Kemper and coworkers investigated the metabolic clearance and biotransformation of 3,7-dimethyloct-6-enenitrile in primary hepatocytes from mice, rats, and humans (Kemper 2006). It was concluded that 3,7-dimethyloct-6-enenitrile was rapidly metabolized in hepatocytes from all species (Mouse: T1/2 = 1.28 min, rat = 2.89 min, human = 2.62 - 19.19 min). Furthermore, it was observed that the major common pathways for biotransformation of 3,7-dimethyloct-6-enenitrile involved

1) epoxidation of the 6-alkenyl moiety followed by conjugation with glutathione,

2) hydroxylation of the terminal methyl group(s) followed by direct conjugation with glucuronic acid in rodents or further oxidation to the corresponding acid in human cells, and

3) hydroxylation of the allylic C5 position.

No evidence for either phase I or phase II metabolism of the conjugated nitrile moiety was obtained.

Potter and coworkers investigated the release of inorganic cyanide from 3,7-dimethyloct-6-enenitrile applied dermally to the rat (400 mg/kg bw) for 24 hours (Potter 2001). Athough statistically significant, only a small measurable increase in the total excretion of urinary thiocyanate, i.e. a marker for endogenously formed inorganic cyanide, was observed for both male and female rats. The increase corresponded to a conversion of nitrile to inorganic cyanide of approx. 0.5%.

Based on the data available, an evident potential for bioaccumulation of 3,7-dimethyloct-6-enenitrile is not identified.