Isoheptane

Specific investigations: other studies

Administrative data

Endpoint:

specific investigations: other studies

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles, acceptable for assessment. Vapour generation and analysis not well documented.

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: supporting information

Reference

Endpoint:

specific investigations: other studies

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles, acceptable for assessment. Vapour generation and analysis not well documented.

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 source

Details on results:

Large increases in respiration were noted in the animals during both exposure periods. No classic alteration in breathing patterns that would be indicative of upper airway irritation was noted in any of the animals.

Conclusions:

Based on these results, exposure to Isooctane at a nominal concentration of 33.52 mg/L of air did elicit an apparent response from the animals upon exposure, however, it did not appear to produce upper airway irritancy in the mice.

Executive summary:

This data is being read across from the source study that tested 2,2,4-trimethylpentane (isooctane) based on analogue read across.

Based on these results, exposure to Isooctane at a nominal concentration of 33.52 mg/L of air did elicit an apparent response from the animals upon exposure, however, it did not appear to produce upper airway irritancy in the mice.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Principles of method if other than guideline:

Respiratory tract irritancy determined by measuring the degree of sensory irritation.

GLP compliance:

yes

Type of method:

in vivo

Endpoint addressed:

respiratory irritation

Test material

Test material information

Constituent 1

Reference substance name:

2,2,4-trimethylpentane

EC Number:

208-759-1

EC Name:

2,2,4-trimethylpentane

Cas Number:

540-84-1

Molecular formula:

C8H18

IUPAC Name:

2,2,4-trimethylpentane

Details on test material:

- Name of test material (as cited in study report): Isooctane
- Analytical purity: 100% pure commercial product

Test animals

Species:

mouse

Strain:

CD-1

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River

Administration / exposure

Route of administration:

inhalation: vapour

Vehicle:

unchanged (no vehicle)

Details on exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: head only exposure chamber
- Source and rate of air: room air

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

2 treatments of 1 minute with 10 minute non-treatment period between each treatment.

Frequency of treatment:

once

Post exposure period:

none

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
99.54 mg/L (corresponding to 21000 ppm)
Basis:
analytical conc.

Doses / concentrations 2

Remarks:

Doses / Concentrations:
33.52 mg/L
Basis:
nominal conc.

No. of animals per sex per dose:

4 males

Control animals:

other: each animal established control breathing pattern prior to treatment by exposure to room air

Results and discussion

Details on results:

Large increases in respiration were noted in the animals during both exposure periods. No classic alteration in breathing patterns that would be indicative of upper airway irritation was noted in any of the animals.

Applicant's summary and conclusion

Conclusions:

Based on these results, exposure to Isooctane at a nominal concentration of 33.52 mg/L of air did elicit an apparent response from the animals upon exposure, however, it did not appear to produce upper airway irritancy in the mice.

Executive summary:

Based on these results, exposure to Isooctane at a nominal concentration of 33.52 mg/L of air did elicit an apparent response from the animals upon exposure, however, it did not appear to produce upper airway irritancy in the mice.