Registration Dossier

Administrative data

basic toxicokinetics
Type of information:
other: Assessment of the toxicokinetic behaviour as can be derived from the available information
Adequacy of study:
weight of evidence
Reason / purpose for cross-reference:
reference to same study

Data source

Reference Type:
study report

Materials and methods

Principles of method if other than guideline:
Review of reports summarised in the dataset

Test material

Constituent 1
Chemical structure
Reference substance name:
Propylidynetrimethanol, propoxylated
EC Number:
EC Name:
Propylidynetrimethanol, propoxylated
Cas Number:
Molecular formula:
C3H5(CH2OR)3 R= (C2H3(CH3)O)nH sum of n: >1 - <6.5 mol PO
Propylidynetrimethanol, propoxylated
Constituent 2
Reference substance name:
not applicable
Molecular formula:
>= C102H156N30O18
not applicable

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
Because of the vapour pressure and water solubility of the commercial material, some of the lower molecular weight components of the substance
are likely to be absorbed via the lung if inhaled. No useful prediction concerning oral absorption can be made on the basis of the logP of the commercial material as there should be a range of values, one for each of the components. Based on read across from pentaerythritol and nitrilotriethanol, it is likely that propylidyne trimethanol is absorbed when administered orally. Propane-1,2-diol and [(methylethylene)bis(oxy)]- dipropanol (and probably, oxydipropanol ) are also absorbed, probably by passive diffusion, when administered orally. Thus it is possible that the smaller polyols may be absorbed. Given the measured logP and water solubility, dermal absorption is likely.
Details on distribution in tissues:
Given the logP values, it is likely that any absorbed oligomers of propoxylated propylidyne trimethanol will be widely distributed in body water. If not
metabolised, it is unlikely that they will accumulate in tissues.
Details on excretion:
In the event that higher molecular weight material is absorbed, it is likely to be excreted in bile. Lower molecular weight unmetabolised oligomer is likely to be excreted in urine. In rat the molecular weight threshold for biliary excretion is around 350, in human it is about 500 (Illing, 1989). The material most likely to be absorbed is likely to be hydrolysed and the products appear in urine, except when the end point of metabolism is carbon dioxide. Carbon dioxide will be exhaled.

Metabolite characterisation studies

Details on metabolites:
Based on information from the propane-1,2-diol trimer [(methylethylene)bis (oxy)]dipropanol, if absorbed, the propane-1,2-diol moiety of the propoxylated propylidyne trimethanol could be further conjugated (with glucuronic acid or sulphate) or stepwise hydrolysed. Propane-1,2-diol is also further metabolised, entering intermediary metabolism via lactic acid/pyruvic acid, and eventually being eliminated as carbon dioxide. Based on read across from pentaerythritol and nitrilotriethanol, it is likely that any propylidyne trimethanol released will be excreted unchanged in the urine.

Any other information on results incl. tables

There are no experimental studies on the toxicokinetics of propoxylated propylidyne trimethanol. The toxicokinetics of propoxylated propylidyne trimethanol is inferred from the core substance and propane-1,2- diol, oxydipropanol and [(methylethylene)bis(oxy)]dipropanol. Propylidyne trimethanol has three free hydroxy groups, thus NLP polyols are likely to consist predominantly of chains of between one and two repeating units, with some chains containing three repeating units.

Applicant's summary and conclusion