Lubricating oils (petroleum), base oils, paraffinic

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Summary study report

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

review article or handbook

Title:

ROBUST SUMMARY OF INFORMATION ON LUBRICATING OIL BASESTOCKS

Author:

American Petroleum Institute

Year:

2003

Bibliographic source:

ROBUST SUMMARY OF INFORMATION ON LUBRICATING OIL BASESTOCKS pag 38-39

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Groups of 5 male and 5 female rats were exposed to oil mists
generated from two highly refined oils. Exposures were by
inhalation six hours each day for a total of 10 days
The two oils were examined in separate experiments.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Two samples of highly refined, solvent extracted dewaxed paraffinic base oil

IUPAC Name:

Two samples of highly refined, solvent extracted dewaxed paraffinic base oil

Test animals

Species:

rat

Strain:

not specified

Sex:

male/female

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure:

not specified

Vehicle:

not specified

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

14 days

Frequency of treatment:

Six hours per day

Doses / concentrations

Remarks:

Doses / Concentrations:
Controls: Air only Oil 1: 55, 507 and 1507 mg/m3 Oil 2: 50, 513 and 1480 mg/m3
Basis:
nominal conc.

No. of animals per sex per dose:

5

Control animals:

yes

Results and discussion

Effect levels

Dose descriptor:

NOAEL

Effect level:

> 50 mg/m³ air

Based on:

not specified

Sex:

male/female

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Oil 1

All treated animals survived to study termination. The fur of all animals was saturated with test material and the amount of material present was clearly related to the exposure concentration. Alopecia and scabs subsequently formed in the highest 2 dose groups. Animals in the highest dose group were relatively unresponsive to auditory stimulation. Decreased body weight associated with a decrease in food consumption was recorded for the high dose animals. Biologically significant increases in relative lung and liver weights were observed in he males and females in the high dose group but only in the mid dose females. An increase in white cell counts and the percentage of neutrophils and a decrease in the percentage lymphocytes was observed in the high dose groups only. There were no treatment related histopathological changes in the lowest 2 dose groups. Animals in the highest dose group exhibited the same changes as those observed in the nasoturbinates and lungs of animals exposed to oil 2.

Oil 2

Clinical observations were the same as for those animals exposed to Oil 1, except that there was no scabbing and no treatment related alterations in food consumption. There was a biologically significant increase in absolute and relative lung weights in males and females at the high dose and in females only at the mid dose. Apart from elevated liver alanine and aspartate transaminase levels in the high dose females there were no other treatment related effects. Histological effects considered to be treatment related consisted of an increase in the amount of perivascular and peribronchial lymphoid proliferations and an increase in mixed inflammatory cell infiltrations in the terminal bronchioles and alveolar ducts of the highest two dose groups. Increases in the appearance of focal hyperplasia and squamous cell metaplasia of the anterior nasal mucosa associated with inflammatory cell infiltration were observed in the two highest dose groups. These changes were indicative of mild irritation of the nasal mucosa.