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The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Toxicological information

Basic toxicokinetics

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Administrative data

basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
key study
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well-documented study report which meets basic scientific principles: pre-GLP

Data source

Reference Type:
study report
Report date:

Materials and methods

Objective of study:
Test guideline
no guideline followed
Principles of method if other than guideline:
Rats were fed 100 mg/kg/day of neodecanoic acid for 5 days. A pulse of C14 labelled neodecanoic acid was administered in the feed and distribution was assessed every 24 hours for 3 days.
GLP compliance:

Test material

Constituent 1
Chemical structure
Reference substance name:
Neodecanoic acid
EC Number:
EC Name:
Neodecanoic acid
Cas Number:
Molecular formula:
2-ethyl-2,5-dimethylhexanoic acid
Details on test material:
Name: neodecanoic acid.

Test animals

not specified
Details on test animals or test system and environmental conditions:
Animals were housed in metabolism cages designed to collect urine and feces

Administration / exposure

Route of administration:
oral: feed
unchanged (no vehicle)
Duration and frequency of treatment / exposure:
5 days
Doses / concentrations
Doses / Concentrations:
Conditioning - 100 mg/kg/day
Pulse - 100 mg/kg
No. of animals per sex per dose / concentration:
8 male and 8 female
Control animals:
yes, concurrent no treatment
Positive control reference chemical:
Details on study design:
The pulse of 25 mg/kg of C14 neodecanoic acid corresponds to approximately 2 microcuries.

Carbon dioxide free air was continually drawn through the metabolism cages at the rate of approximately 500 ml/min. The expired CO2 mixed with the air was passed thought a solution of ethanolamine in ethanol. The scrubbing solution was changed every 24 hours. Urine and feces samples were collected at 24 hour interval. At the conclusion of the experiment the case was rinsed and the washings collected. At that time the animals were sacrificed, examined, and dissected. A completely closed material balance was attempted. All samples were counted by liquid scintillation.
Not applicable

Results and discussion

Preliminary studies:
No additional data.

Toxicokinetic / pharmacokinetic studies

Details on absorption:
Not applicable.
Details on distribution in tissues:
Not applicable.
Details on excretion:
Bulk activity was found in the feces and urine. Expired air contained less that 0.5% of the dose. The rate of excretion pattern seems consistent in all cases. Activity in both urine and feces falls off rapidly and indicate that further significant activity will not be forthcoming. The expired air samples indicate a peak rate of excretion around 12 hours and probably before. Representative fat, muscle, and blood samples showed specific activities near the measurable limit of 0.003% of the dose per gram. Of all tissues examined, the gastrointestinal tract showed the greatest specific activity. Total retained by the stomach was 0.02% of dose.

Metabolite characterisation studies

Metabolites identified:
not measured
Details on metabolites:
Not applicable.

Applicant's summary and conclusion

Interpretation of results (migrated information): no bioaccumulation potential based on study results
Executive summary:

In this study, rats were fed 100 mg/kg/day of neodecanoic acid for 5 days and followed by a pulse of C-14 labeled neodecanoic acid and assessed every 24 hours for 3 days to determine the distribution and excretion. It was found that under the conditions of the experiment, 70-80% of the administered activity could be accounted for.  Excretion in the urine may expect to range from 50-60% while that in the feces will vary from 40-50%.  In any case, the total of these two will be at least 98%.  The excretion rate falls off rapidly such that less than 1% of dose is expected past 72 hours.  Expired air reaches a peak rate somewhere around 12 hours or earlier.  The total carcass, exclusive of organs, retains less than 1% of the recovered dose.  Intestines had the greatest specific activity and contribute as much as 1% of total dose.  Analysis by thin layer chromatography shows that the bulk of excreted activity is either the original free acid or a material which is readily converted to the acid upon mild hydrolysis.