Reaction mass of 1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate and (1S,2S,4S)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate

Specific investigations: other studies

Administrative data

Endpoint:

specific investigations: other studies

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: No GLP compliance and no data on guidelines requirements.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1974

Report date:

1974

Materials and methods

Principles of method if other than guideline:

Exposure of rats to 44 different odour substances and examination of olfactory bulbs.

GLP compliance:

no

Type of method:

in vivo

Endpoint addressed:

not applicable

Test material

Test material information

Constituent 1

Reference substance name:

Exo-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate

EC Number:

204-727-6

EC Name:

Exo-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate

Cas Number:

125-12-2

Molecular formula:

C12H20O2

IUPAC Name:

(1S,2S,4S) 1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate

Test animals

Species:

rat

Strain:

Wistar

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 2 weeks
- Weight at study initiation: 28-39 g
- Housing: cylindrical cages, with closed tops

ENVIRONMENTAL CONDITIONS
- Air changes: 0,6 litre X sec-1

Administration / exposure

Route of administration:

inhalation

Vehicle:

unchanged (no vehicle)

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Each substance was introduced into the air stream from a glass bottle, the content of which was weighed before and after the experiments to measure the concentration of substance in the stream.

Duration of treatment / exposure:

For IBA: 4 weeks and 8 weeks

Frequency of treatment:

Continous

Doses / concentrations

Remarks:

Doses / Concentrations:
7.9 E(-9) M
Basis:
analytical conc.

No. of animals per sex per dose:

For IBA: 3 animals

Control animals:

yes

Results and discussion

Any other information on results incl. tables

Administration of IBA 7.9 E-9 M (1.551 mg/m³):

after 4 weeks: mean weight of animals at sacrifice: 107 g

after 8 weeks: mean weight of animals at sacrifice: 220 g

Applicant's summary and conclusion

Conclusions:

For IBA was observed a specific pattern of mitral cell degeneration in the olfactory bulb: a heavy 'degeneration' of granule cells in the ventral area of the bulb.

Executive summary:

Rats have been exposed to a variety of constant odorous environments from 2 weeks of age for periods from 1 to 12 weeks. They have been compared with control litter-mates exposed to a non-odorised milieu for the same periods. For each of 44 different odours a specific pattern of mitral cell degeneration was observed in the olfactory bulb; the pattern and extent of this 'selective degeneration' did not appear to be correlated with the concentration of the odorant. The pattern of degeneration in coronal sections was maintained through the antero-posterior extent of the bulb in most cases. These results suggest a topological representation of different odours in the olfactory bulb. The implications of selective degeneration in the study of odour-quality discrimination are discussed.