Registration Dossier

Administrative data

Endpoint:
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
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007

Materials and methods

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

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
Given the vapour pressure and water solubility of the commercial material it is likely that some of the lower molecular weight elements are absorbed via the lung. Given the water solubility and logP of propoxylated pentaerythritol, it is likely to be absorbed orally. Pentaerythritol is well (>50%) and rapidly absorbed following oral administration to mouse or dog. At the pH of the stomach and upper intestine it is likely that the substance is unionised, but ionisation is likely at the pH prevailing lower in the intestine. Propane-1,2-diol,oxydipropanol and [(methylethylene)bis(oxy)]dipropanol are also absorbed, probably by passive diffusion, when administered orally. Thus it is likely that oligomers may be absorbed. Given the logP it is likely that the NLP polyols are absorbed dermally.
Details on distribution in tissues:
Given the logP values, it is likely that any absorbed oligomers of propoxylated pentaerythritol will be widely distributed and 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. 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 dioxideCarbon dioxide will be exhaled. If the hydrolysis is taken to completion, the pentaerythritol is likely to be excreted in urine without further metabolism.

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 pentaerythritol 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. Pentaerythritol, if released, is unlikely to be further metabolised in rat, mouse dog or human.

Any other information on results incl. tables

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

Applicant's summary and conclusion