Registration Dossier

Administrative data

Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
no data available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study is sufficiently documented. OECD Guideline study; analytical purity of test substance: 68,3%.

Data source

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

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
Deviations:
no
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
See confidential details on test material section


Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Dr. K Thomae GmbH
- Age at study initiation: about 7 weeks
- Weight at study initiation: males: mean = 230 g; females: mean = 177 g
- Housing: single
- Diet: ad libitum during post exposure observation period
- Water: ad libitumduring post exposure observation period

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
other: Inhalation: dust aerosol
Type of inhalation exposure:
nose/head only
Vehicle:
air
Remarks on MMAD:
MMAD / GSD: 0.8 mg/m³: 3.3 µm
8 mg/m³: 3.3 µm
80 mg/m³: 3.1 µm
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: aerodynamic exposure apparatus (INA 60, Volume ca. 90 L, BASF AG)
- Method of holding animals in test chamber: The rats were restrained in exposure tubes (glass tubes), their snouts projected into the inhalation chamber and they thus inhaled the dust aerosol.
- System of generating particulates/aerosols: brush generator
- Temperature, humidity, pressure in air chamber: 22°C, 50% humidity
- Method of particle size determination: cascade imapactor

TEST ATMOSPHERE
- Brief description of analytical method used: Spectrophotometric analysis
- Samples taken from breathing zone: yes
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
no data available
Duration of treatment / exposure:
6 hours per day for 28 days
Frequency of treatment:
5 days per week
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:
0, 0.8, 8, 80 mg/m³
Basis:
nominal conc.
Remarks:
Doses / Concentrations:
0, 0.86, 8.1, 82 mg/m³
Basis:
analytical conc.
No. of animals per sex per dose:
5
groups of female rats (5 animals) were hold without further exposure for an about 4-week post exposure
Control animals:
yes, concurrent vehicle
Details on study design:
no data available
Positive control:
no data available

Examinations

Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations: mortality, behavior and state of health

DETAILED CLINICAL OBSERVATIONS: No

OPHTHALMOSCOPIC EXAMINATION: No

BODY WEIGHT: Yes
- Time schedule for examinations: each week

HAEMATOLOGY: Yes
- Time schedule for collection of blood: after 28 day exposure period and after post-exposure observation period
- Anaesthetic used for blood collection: No data
- Animals fasted: No
- How many animals: all
- Parameters checked: leukocytes, erythrocytes, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelets, differential blood count, thromboplastin time

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: after 28 day exposure period and after post-exposure observation period
- Animals fasted: No
- How many animals: all
- Parameters checked: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, sodium, potassium, chloride, inorganic phosphate, calcium, urea, creatinine, glucose, total bilirubin, total protein, albumin, globulins, triglycerides, cholesterol

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No
Sacrifice and pathology:
GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes
Other examinations:
None
Statistics:
Clinical examinations
Means and standard deviation were calculated for the variables (body weight and body weight gain/body weight change) of the animais of each test group for the statistical evaluation of the study. Statistical relevance was established using methods of ANOVA and DUNNETT.
Clinical chemistry and hematology
Mean and standard deviation were calculated for each test group and tabulated together with the individual values.
Except of the differential blood count, a non-parametric one-way analysis of variance is done via the Kruskal-Wallis-h-test. If the resulting p-value is equal or less than 0.05 a pairwise comparison of each dose group with the control group was carried out. This comparison is done using the Mann-Whitney-U-test for the hypotheses of equal medians.

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
statistically significant retarded body weight change in male rats
Food consumption and compound intake (if feeding study):
not specified
Food efficiency:
not specified
Water consumption and compound intake (if drinking water study):
not specified
Ophthalmological findings:
not examined
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
not examined
Behaviour (functional findings):
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Histopathological findings: neoplastic:
effects observed, treatment-related
Details on results:
CLINICAL SIGNS AND MORTALITY:
80 mg/m³: no substance related effects
8 mg/m³: no substance related effects
0.8 mg/m³: no substance related effects
No mortalities were recorded throughout the exposure period.

BODY WEIGHT AND WEIGHT GAIN:
80 mg/m³: statistically significant retarded body weight change in male rats
8 mg/m³: no substance related effects
0.8 mg/m³: no substance related effects

HAEMATOLOGY:
all groups: no substance related effects

CLINICAL CHEMISTRY:
80 mg/m³: no substance related effects; 8 mg/m³: no substance related effects; 0.8 mg/m³: no substance related effects

ORGAN WEIGHTS:
80 mg/m³: increased absolute and relative lung weights (females and males); in the post exposure observation group a trend towards increased absolute and relative lung weights were still seen
8 mg/m³: increased absolute and relative lung weights which was still apparent in the post exposure observation group
0.8 mg/m³: no substance related effects

GROSS PATHOLOGY:
80 mg/m³: no substance related effects; 8 mg/m³: no substance related effects; 0.8 mg/m³: no substance related effects

HISTOPATHOLOGY:
80 mg/m³: lungs: hypertrophy of goblet cells (male and females), interstitial pneumonitis (increased in grading; males and females), increased connective tissue content (males and females)
nasal cavity (level 1): focal metaplasia of the respiratory epithelium (males and females)
post exposure observation period: increased connective tissue content lungs
8 mg/m³: no substance related effects
0.8 mg/m³: no substance related effects

Effect levels

open allclose all
Dose descriptor:
NOAEL
Remarks:
local
Effect level:
0.86 mg/m³ air (analytical)
Based on:
test mat.
Remarks:
(equivalent to the substance as registered)
Sex:
male/female
Basis for effect level:
other: based on the absence of local effects
Dose descriptor:
LOAEL
Remarks:
local
Effect level:
8.1 mg/m³ air (analytical)
Based on:
test mat.
Remarks:
(equivalent to the substance as registered)
Sex:
male/female
Basis for effect level:
other: based on the effects on lung weight
Dose descriptor:
NOAEL
Remarks:
systemic
Effect level:
82 mg/m³ air (analytical)
Based on:
test mat.
Remarks:
(equivalent to the substance as registered)
Sex:
male/female
Basis for effect level:
other: based on the absence of toxicologically significant systemic effects

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
In a repeated dose inhalation toxicity study conducted according to OECD Guideline 412 (1990), groups of male and female Wistar rats (5/sex) were exposed by the inhalation route to the test substance as dust aerosol for 6 hours per day on 5 days per week for 4 weeks (28-day test) to head/nose at concentrations of 0, 0.8, 8, 80 mg/m³ (nominal concentrations) or 0, 0.86, 8.1, 82 mg/m³ (analytical concentrations). Based on the results of this study, 82 mg/m³ of test item was established as the No Observed Adverse Effect Level (NOAEL) systemic based on the absence of toxicologically significant systemic effects; 0,86 mg/m³ of test item was established as the No Observed Adverse Effect Level (NOAEL) local and 8.1 mg/m³ of test item was established as the Lowest Observed Adverse Effect Level (LOAEL) local based on the effects on lung weight. Therefore, reaction product of naphthalene, butanol, sulfonated and neutralized by caustic soda is not classified for repeated dose toxicity according to the classification criteria of the Regulation (EC) 1272/2008 (CLP) and of the Directive 67/548/EEC.
Executive summary:

In a repeated dose inhalation toxicity study according to OECD Guideline 412 (1990), groups of male and female Wistar rats (5/sex) were exposed by the inhalation route to the test substance as dust aerosol for 6 hours per day on 5 days per week for 4 weeks (28-day test) to head/nose at concentrations of 0, 0.8, 8, 80 mg/m³ (nominal concentrations) or 0, 0.86, 8.1, 82 mg/m³ (analytical concentrations). Groups of 5 female rats were hold without further exposure for an about 4-week post-exposure observation period to obtain informations on persistency, progression or regression of effects.

No mortality and no clinical signs were reported throughout the study whatever the dose level. Body weight gain was reduced in high dose males only. There were no test item-related effects on hematology and clinical chemistry parameters at any dose levels. No macroscopic findings were reported at necropsy. An increase of absolute and relative lung weights in male animals was observed at 82 mg/m³ and in female animals at 8.1 and 82 mg/m³. Histopathologically, goblet cell hyperplasia was reported in the bronchi of both sexes at 82 mg/m³. Furthermore, the grade of severity of pneumonitis that occurred also in control animals was slightly increased in the animals at 82 mg/m³, as was there a slight increase in the content of connective tissue of the lungs. In the nasal cavity, focal metaplasia of the respiratory epithelium to stratifying epithelium was noted in the animals at 82 mg/m³ at the transition of the stratifying epithelium to respiratory epithelium. After a 4-week recovery period (females only), the lungs of the animals at 82 mg/m³ showed only a slight reparative increase of mature connective tissue. Focal metaplasia in the nasal cavity was evident in only 2 animals at 82 mg/m³.

Based on the results of this study, 82 mg/m³ of test item was established as the No Observed Adverse Effect Level (NOAEL) systemic based on the absence of toxicologically significant systemic effects; 0,86 mg/m³ of test item was established as the No Observed Adverse Effect Level (NOAEL) local and 8.1 mg/m³ of test item was established as the Lowest Observed Adverse Effect Level (LOAEL) local based on the effects on lung weight.

Therefore, reaction product of naphthalene, butanol, sulfonated and neutralized by caustic soda is not classified for repeated dose toxicity according to the classification criteria of the Regulation (EC) 1272/2008 (CLP) and of the Directive 67/548/EEC.