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Reference
Endpoint:
basic toxicokinetics in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1994-1995
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Objective of study:
absorption
Qualifier:
no guideline followed
Principles of method if other than guideline:
The aim of this study was to investigate the absorption of TMP in an in vitro study using everted rat intestinal sacs.
GLP compliance:
no
Radiolabelling:
no
Species:
other: in vitro

Calculated amount of DMP absorbed into serosal fluid 

Sample

Calculated amount of DMP absorbed into serosal fluid (µmoles)

Mean (µmoles)

±SD

 

 

 

 

Serosal fluid 1 Rat 1

15.995

 

 

Serosal fluid 2 Rat 1

13.780

 

 

Serosal fluid 3 Rat 1

13.992

14.589

1.222

 

 

 

 

Serosal fluid 1 Rat 2

15.271

 

 

Serosal fluid 2 Rat 2

15.094

 

 

Serosal fluid 3 Rat 2

16.922

15.762

1.008

 

 

 

 

External media 60 min

19.551

 

 

Original concentrations of 20µmoles/400µL (Total incubation volume of 10mL)

Conclusions:
From these results it can be concluded that DMP was extensively absorbed into the intestinal sacs.
Executive summary:

The absorption of DMP was investigated in vitro using an everted rat gut sac model. The results of the study indicate that DMP was extensively absorbed into the intestinal sacs.

Description of key information

The absorption of DMP was investigated in vitro using an everted rat gut sac model. The results of the study indicate that DMP was extensively absorbed into the intestinal sacs. A theoretical assessment of the toxicokinetic properties of the substance is also presented.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential
Absorption rate - oral (%):
50
Absorption rate - dermal (%):
50
Absorption rate - inhalation (%):
100

Additional information

The absorption of DMP was investigated in vitro using an everted rat gut sac model. The results of the study indicate that DMP was extensively absorbed into the intestinal sacs.

A theoretical assessment is also made for the two components of the substance.

The component 2 -ethyl-2 -(methoxymethyl)-propane-1,3 -diol is of low molecular weight and high water solubility, properties which would favour absorption. The component is also predicted to be orally bioavailable (Lipinski rule, OASIS) and metabolised by sequential oxidation to the corresponding aldehydes and carboxylic acids and by hydrolysis. The resulting low molecular weight water-soluble metabolites are likely to be readily excreted in the urine. Bioaccumulation is not predicted.

The component 2-ethylpropane-1,3-diol is of low molecular weight and high water solubility, properties which would favour absorption. The component is also predicted to be orally bioavailable (Lipinski rule, OASIS) and metabolised by sequential oxidation to the corresponding aldehyde and carboxylic acid. These two low molecular weight water-soluble metabolites are likely to be readily excreted in the urine. Bioaccumulation is not predicted.

In the absence of quantitative data, default assumptions are made for the relative bioavailability of DMP Tech by different exposure routes.