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In general, Aliphatic alcohols are absorbed by all common routes of exposure widely distributed within the body and eliminated. The initial step in the mammalian metabolism of primary alcohols is the oxidation to the corresponding carboxylic acid, with the corresponding aldehyde being a transient intermediate. These carboxylic acids are susceptible to further degradation via acyl-Coa intermediates by the mitochondrial beta-oxidation process. The acid formed from the longer chained aliphatic alcohol can also enter the lipid biosynthesises and may be incorporated in phospholipids and neutral lipids and is subsequently completely oxidized to carbon dioxide and water.

Similar to the dermal absorption potential, it is expected that orally administered aliphatic alcohols also show a chain length dependant potential for gastro absorption, with shorter chain aliphatic alcohols having a higher absorption potential than longer chain alcohols.

The long chain aliphatic carboxylic acids are efficiently eliminated and aliphatic alcohols are therefore not expected to have a tissue retention or bioaccumulation potential (Bevan 2001)[1].


[1]Bevan, C. Monohydric Alcohols C7 to C18, Aromatic and other alcohols. Patty’s Toxicology, 5 th Edition (Vol 6), 2001. E bingham, B Cohrssen and C.H. Powell eds.J.Wiley & sons,[1]

No experimental toxicokinetic study is available on the Heptanol but additional information on absorption, distribution, metabolism and excretion may be deduced from the following physicochemical properties:

-Molecular weight: the molecular weight ranges from 116.2 g/mol,

-Water solubility:  the water solubility measured at 20°C according to OECD guideline 105 is 1.63 g/L,

-Partition coefficient Log Kow:  the Log Kow measured according to OECD guideline 117 is equal to 2.2 at 20°C,

- Vapour pressure at 20°C: 70 Pa.

Absorption

The value of the log Kow, the high water solubility and the low molecular weight suggest and confirm a high absorption of Heptanol into the gastrointestinal tract after oral absorption.

This assumption of high oral absorption is confirmed in the oral toxicity studies with the systemic effects traduced by mortalities.

Dermal and inhalation absoption are also anticipated takein into account the Partition coefficient and the vapour pressure of 70 Pa.

Distribution and Metabolism
By the dermal route, the substance is highly hydrophilic and highly soluble (1.63 g/l) with a low molecular weight, absorption is anticipated to be high and heptanol is anticipated to easily penetrate the stratum corneum. By the inhalation route, taken into account the vapour pressure, heptanol is anticipated to have a low volatility , furthermore, vapours of very hydrophilic substance may be retained within the mucust, his may explained the absence of toxicity in the acute inhalation study at the maximum saturated concentration.
Elimination
Due to the high water solubility and a relatively low molecular mass, the excretion of the substance in urine is highly expected.