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Administrative data

Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1990
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report date:
1990

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
GLP compliance:
yes

Test material

Constituent 1
Reference substance name:
Sodium diisobutylnaphthalenesulphonate
EC Number:
248-326-4
EC Name:
Sodium diisobutylnaphthalenesulphonate
Cas Number:
27213-90-7
Molecular formula:
Not applicable (UVCB substance)
IUPAC Name:
sodium 2,3-bis(2-methylpropyl)naphthalene-1-sulfonate
Test material form:
solid: particulate/powder

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female

Administration / exposure

Route of administration:
inhalation: aerosol
Type of inhalation exposure:
nose/head only
Remarks on MMAD:
MMAD / GSD: MMAD= 3.1 - 3.3 um
Duration of treatment / exposure:
28 days
Frequency of treatment:
6 hours per day; 5 days per week
Doses / concentrations
Remarks:
Doses / Concentrations:
0.8, 8, 80 mg/m3
Basis:
nominal conc.
No. of animals per sex per dose:
5 male/female rats
Control animals:
yes

Results and discussion

Effect levels

Dose descriptor:
NOEL
Effect level:
0.8 mg/m³ air
Based on:
test mat.
Sex:
male/female
Basis for effect level:
organ weights and organ / body weight ratios

Target system / organ toxicity

Critical effects observed:
not specified

Any other information on results incl. tables

The following findings were obtained and assessed to be related to the inhalation of the test substance:

80 mg/m3 group

main group

Clinical examinations

-         retarded body weight change (male rats)

Clinical chemistry and hematology

-         no substance-related effects

Relative and absolute organ weights

-         increased absolute and relative lung weights (males and females)

Macroscopic lesions

-         no substance-related effects

Microscopic lesions

lungs:

-         hypertrophy of goblet cells (male and females)

-         interstitial pneumonitis (increased in grading; males and females)

-         increased connective tissue content (male and females)

nasal cavity (level 1):

-         focal metaplasia of the respiratory epithelium (males and females)

 

80 mg/m3 group

post-exposure observation group. Females

Clinical examinations

-         no substance-related effects

Relative and absolute lung weights

-         trend towards increased absolute and relative lung weigths

Macroscopic lesions

-         no substance-related effects

Microscopic lesions

-         increased connective tissue content lungs

 

8 mg/m3 group

main group

Clinicalexaminations, clinical chemistry and hematology. macroscopic and microscopic lesions

-         no substance-related effects

Relative and absolute organ weights

-         increased absolute and relative lung weights

 

8 mg/m3 group

post-exposure observation group. females

Clinical examinations. macroscopic and microscopic lesions

-         no substance-related effects

Relative and absolute organ weights

-         increased absolute and relative lung weights

 

0.8 mg/m3 groups:

main and post-exposure observation groups

-         no substance-related effects

Applicant's summary and conclusion

Conclusions:
The test substance induced unspecific toxic effects in the nasal cavity and lungs as known from the inhalation of mild irritants. The lesions are reversible except the increase of connective tissue in the lungs which is seen as a reparative process after the inhalation of a mild irritant.
The no-observed-effect-level (NOEL) under the conditions of the test is 0.8 mg/m3.

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