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Toxicological information

Basic toxicokinetics

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Administrative data

Endpoint:
basic toxicokinetics
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: The documentation is from secondary literature.
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.
Cross-reference
Reason / purpose for cross-reference:
read-across source
Reference
Endpoint:
basic toxicokinetics
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: The documentation is from secondary literature.
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.
Reason / purpose for cross-reference:
read-across: supporting information
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 417 (Toxicokinetics)
Principles of method if other than guideline:
The metabolism of p-tert-butyltoluene (TBT) was studied in the rat and guinea pig.
GLP compliance:
not specified
Radiolabelling:
not specified
Species:
rat
Strain:
not specified
Sex:
not specified
Route of administration:
oral: gavage
Vehicle:
not specified
Control animals:
no
Metabolites identified:
yes
Details on metabolites:
The major urinary metabolites in rats were p-tert-butylbenzoic acid and its alcohol derivative 2-(p-carboxyphenyl)-2-methylpropan-1-ol whereas p-tert-butylbenzoylglycine was the most prominent metabolite in guinea pig urine.
Conclusions:
Interpretation of results: low bioaccumulation potential based on study results
Executive summary:

The metabolism of p-tert-butyltoluene (TBT) was studied in the rat and guinea pig. Both the methyl and the tert.-butyl group were oxidized to alcohol and carboxylic acid derivatives in these species. The major urinary metabolites in rats were p-tert-butylbenzoic acid and its alcohol derivative 2-(p-carboxyphenyl)-2-methylpropan-1-ol whereas p-tert-butylbenzoylglycine was the most prominent metabolite in guinea pig urine. No significant differences in metabolism were found when TBT was given intragastrically or by inhalation. The intragastric administration of 14C-TBT to rats showed that the bulk of the excretion of radioactivity occurred within three days. A recovery of 83% was achieved and the ratio of urinary/faecal radioactivity was roughly 3.5:1.

Data source

Materials and methods

Test material

Constituent 1
Chemical structure
Reference substance name:
Hydrocarbons, C10, aromatics, >1% naphthalene
EC Number:
919-284-0
Cas Number:
Not applicable
Molecular formula:
None available - not a single isomer - see remarks
IUPAC Name:
Hydrocarbons, C10, aromatics, >1% naphthalene
Test material form:
liquid
Details on test material:
Name of substance: Hydrocarbons, C10, aromatics, >1% naphthalene
EC# 919-284-0

Results and discussion

Metabolite characterisation studies

Metabolites identified:
yes
Details on metabolites:
The major urinary metabolites in rats were p-tert-butylbenzoic acid and its alcohol derivative 2-(p-carboxyphenyl)-2-methylpropan-1-ol whereas p-tert-butylbenzoylglycine was the most prominent metabolite in guinea pig urine.

Applicant's summary and conclusion

Conclusions:
Interpretation of results: low bioaccumulation potential based on study results
Executive summary:

This data is being read across from the source study that tested 1-tert-butyl-4-methylbenzene based on analogue read across.

The metabolism of p-tert-butyltoluene (TBT) was studied in the rat and guinea pig. Both the methyl and the tert.-butyl group were oxidized to alcohol and carboxylic acid derivatives in these species. The major urinary metabolites in rats were p-tert-butylbenzoic acid and its alcohol derivative 2-(p-carboxyphenyl)-2-methylpropan-1-ol whereas p-tert-butylbenzoylglycine was the most prominent metabolite in guinea pig urine. No significant differences in metabolism were found when TBT was given intragastrically or by inhalation. The intragastric administration of 14C-TBT to rats showed that the bulk of the excretion of radioactivity occurred within three days. A recovery of 83% was achieved and the ratio of urinary/faecal radioactivity was roughly 3.5:1.