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Administrative data

Description of key information

The LD50 by ingestion was estimated to be between 1000 to 2000 mg/kg bw.

The LD50 by dermal exposure was estimated to be >880 mg/kg bw.

The LC50 by inhalation exposure (dust) was estimated to > 97 mg/m3.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Qualifier:
no guideline required
Principles of method if other than guideline:
- Principle of test: Standard acute method
- Short description of test conditions: Four mice (2/sex) were exposed to 1-naphthol at doses of 500, 1000 and 2000 mg/kg bw in propane-1,2-diol by gavage.
GLP compliance:
no
Test type:
standard acute method
Limit test:
no
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: No data
- Expiration date of the lot/batch:No data
- Purity test date: No data
- Purity : no data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: No data
- Stability under test conditions: No data
- Solubility and stability of the test substance in the solvent/vehicle: No data
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No data

TREATMENT OF TEST MATERIAL PRIOR TO TESTING No

FORM AS APPLIED IN THE TEST : Suspension
Species:
mouse
Strain:
CD-1
Remarks:
Cr1: CD-1 (ICR)BR)
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River UK limited
- Age at study initiation: 6-7 weeks old
- Weight at study initiation: No data
- Housing: solid-bottomed cages
- Diet (ad libitum): Porton rat Diet Pellets (Labsure Animal Food Ltd. Poole, Dorset)
- Water (ad libitum): filtred tap-water
- Acclimation period: yes - 2 weeks

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 to 22°C
- Humidity (%): 40-60%
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12h light/ 12h black

Route of administration:
oral: gavage
Vehicle:
other: propane-1,2-diol-water (1:1 v/v)
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 1/1
- Amount of vehicle (if gavage): 10 ml/kgbw
- Justification for choice of vehicle: No data
- Lot/batch no. (if required): No data
- Purity: No data

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kgbw
Doses:
500, 1 000 and 2 000 mg/kgbw
No. of animals per sex per dose:
2 per sex per dose
Control animals:
yes
Remarks:
one untreated and one with the vehicle
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: No data
- Necropsy of survivors performed: yes (colon, duodenum, gall bladder, heart, ileumn kidneys, liver, lungs, parathyroid, gland, stomach (forestomach and glandular region) and thyroid gland
- Other examinations performed: clinical signs, body weight,, clinical chemistry (ALT, ALP, GLDH, TP, ALB, BUN, CREA, GLU) and heamatology analyses (Hgb, RBC, Hct, Plt, WBC)
Statistics:
From the heamatology and clinical chemistry data generated in these studies, arithmetic means and standard deviations were calculated.
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 1 000 - < 2 000 mg/kg bw
Based on:
test mat.
Mortality:
The mice dosed at 2000 mg/kgbw became subdued shortly after treatment developed abnormal respiration and tremors and finally suffered total collapse. All of the animals in this dose group were killed in extremis between 15 and 90 min after dosing.
One male in the low-dose (500 mg/kgbw) group was killed in extremis approximately 2 hours after dosing.
Clinical signs:
The animals treated at 1000 mg/kgbw also showed subdued behaviour with piloerection, but recovered for the signs.
The other animals in the 500 mg/kgbw group, although showing subdued behaviour, laboured respiration and piloerection, recovered to survive to the end fo the study.
Body weight:
No data
Gross pathology:
No data
Other findings:
- Histopathology:
Renal changes (1) eosinophilic deposits in the lumen of the distal tubules and collecting ducts associated with degeneration of the distal tubular epithelia were seen in the 3 male mice killed at 2000 mg/kgbw and 1 to 500 mg/kgbw. and 1 female mice dosed at 1000 mg/kgbw (both of which survived) (2) papillary necrosis with an associated intravascular thrombosis in one male and both female mice receiving 1000 mg/kgbw and (3) marked dilatation of both corical and medullary tubules in both female mice dosed at 1000 mg/kgbw.
Gastric changes consisted of lesions in the forestomach and glandular region. These changes are seen in all but one of the mice dosed at 1000 and 500 mg/kgbw, included focal splitting of the squamous epithelium which was generally associated with vascular congestion and an acute inflammatory cell infiltration. Sloughing of the superficial epithelium of the glandular mucosa was observed in all mice dosed at 2000 mg/kgbw, in one male and one female mouse receiving 500 mg/kgbw. Generally, this change was associated with vascular congestion and an acute inflammatory cell inflitration.
- Potential target Organs : No data
- Other observations: no differences in the haematology or clinical chemistry data obtained from the control goup and those dosed with naphthol.
Interpretation of results:
other: study not considered for classification, but effect level is in line with harmonized Cat 4 classification
Remarks:
Note: substance has a harmonized classification as Cat 4
Conclusions:
The LD50 was estimated to be between 1000 to 2000 mg/kg bw.
Executive summary:

Four mice (2/sex) were exposed to 1-naphthol at doses of 500, 1000 and 2000 mg/kg bw in propane-1,2-diol by gavage. One male in the 500 mg/kg bw group was killed in extremis two hours post dosage. Other animals in this group showed piloerection and laboured respiration. Animals in the 1000 mg/kg bw group showed piloerection, but survived to the end of the study. Shortly after dosing animals exposed to 2000 mg/kg bw showed abnormal respiration and soon after dosing collapsed. All animals in this dosage group were killed in extremis from 15 to 90 minutes.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
Value:
1 000 mg/kg bw
Quality of whole database:
Klimisch 2

Acute toxicity: via inhalation route

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Referenceopen allclose all

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1980
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Principles of method if other than guideline:
Not specified, but based on the key information provided, it is scientifically acceptable.
GLP compliance:
not specified
Test type:
other: Not specified
Specific details on test material used for the study:
Substance identity provided with CAS number and purity (> 99% w/w)
Species:
rat
Strain:
Wistar
Sex:
female
Route of administration:
inhalation: dust
Type of inhalation exposure:
not specified
Vehicle:
other: presumed as air
Remark on MMAD/GSD:
details not provided
Details on inhalation exposure:
Dust was generated using a Wright Dust-Feed-Through with an air flow of 19 liters/min at 5psi. Dust was delivered to a 120 liter Plexiglass chamber containing 6 animals. Temperature of the chamber was 24 degrees C.
Analytical verification of test atmosphere concentrations:
yes
Remarks:
concentrations were measured gravimetrically every 30 min.
Duration of exposure:
4 h
Concentrations:
Not clear but at least one concentration of 97 mg/m3 is described.
No. of animals per sex per dose:
6
Control animals:
no
Details on study design:
Dust was generated using a Wright Dust-Feed-Through with an air flow of 19 liters/min at 5psi. Dust was delivered to a 120 liter Plexiglass chamber containing 6 animals. Temperature of the chamber was 24 degrees C. Six female Wistar rats were exposed for 4 hours.
Sex:
female
Dose descriptor:
LC50
Effect level:
> 97 mg/m³ air (analytical)
Based on:
not specified
Exp. duration:
4 h
Mortality:
None
Clinical signs:
other: Signs of toxicity included eye irritation, salivation and ataxia.
Body weight:
Not provided
Gross pathology:
Not provided (no deaths)
Interpretation of results:
other: STOT SE Category 3
Conclusions:
The LC50 was determined to be > 97 mg/m3 based on a 4 hour exposure of the test substance as dust. No deaths occured and the substance is not classifiable for Acute Toxicity - Inhalation by UN GHS criteria. Howerver, based on clinical symptoms including ataxia, per UN GHS criteria, it is classifed under STOT SE Category 3.
Executive summary:

Dust was generated from CAS no. 90 -15 -3 using a Wright Dust-Feed-Through with an air flow of 19 liters/min at 5psi.

Temperature of the chamber was 24 degrees C. Dust was delivered to a 120 liter Plexiglass chamber containing 6 Wistar

rats (female). Animals were exposed for 4 hours. Concentrations were measured. No deaths occured.

The LC50 was determined to be > 97 mg/m3 based on a 4 hour exposure of the test substance as dust. Under the conditions of the test and the results reported, the substance does not meet the UN GHS criteria for classification for Acute Toxicity -inhalation. However, signs of toxicity observed included eye irritation, salivation and ataxia. Accordingly, per UN GHS criteria, the substance is classified as STOT SE Category 3. (H335)

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1991
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
secondary literature
Remarks:
Methodology details missing
Principles of method if other than guideline:
Not specified
GLP compliance:
not specified
Test type:
other: Not specified
Specific details on test material used for the study:
Test material is identified by the CAS number in report (IUCLID 2003) and EPA 86-920000514S.
Species:
rat
Strain:
not specified
Remarks:
albio rats
Sex:
male
Details on test animals and environmental conditions:
None provided
Route of administration:
inhalation: dust
Type of inhalation exposure:
not specified
Vehicle:
not specified
Details on inhalation exposure:
Exposure time: 1 hour
Analytical verification of test atmosphere concentrations:
yes
Remarks:
concentration derived from dust sample collection in chamber
Duration of exposure:
ca. 60 min
Remarks on duration:
Lower than the current guideline duration.
Concentrations:
420 mg/m3
No. of animals per sex per dose:
six
Control animals:
no
Details on study design:
Not provided
Sex:
male
Dose descriptor:
LC0
Effect level:
> 420 mg/m³ air
Based on:
test mat.
Exp. duration:
60 min
Mortality:
None
Clinical signs:
other: lacrimation and salivation
Body weight:
provided
Gross pathology:
no significant findings
Other findings:
Toxic effects: Sense organs and special senses (Nose, Eye, Ear, and Taste) -Lacrimation
Gastrointestinal - Changes in structure and function of salivary glands
Interpretation of results:
GHS criteria not met
Remarks:
Note: the substance has a harmonized classification as STOT SE 3
Conclusions:
The L0 was > 420 mg/m3 based on 1 hour exposure (as dust) to male albino rats. This does not meet the UN GHS criteria for classification for Acute toxicity - Inhalation.
Executive summary:

The L0 was > 420 mg/m3 based on 1 hour exposure (as dust) to six male albino rats.No deaths were reported.

Toxic effects: Sense organs and special senses (Nose, Eye, Ear, and Taste) -Lacrimation

                       Gastrointestinal - Changes in structure and function of salivary glands

Under the conditions of this study, and the available information, the test item does not meet UN GHS criteria for classification.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LC50
Value:
97 mg/m³
Quality of whole database:
Klimisch 2

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1991
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Principles of method if other than guideline:
Method of Draize and associates was used (Draize et al, J. Pharmacol. Exp. Therap., 82: 377 (1944)
GLP compliance:
no
Test type:
standard acute method
Limit test:
no
Specific details on test material used for the study:
The material was either in commercial production or have been evaluated for commerical potential.
Species:
rabbit
Strain:
New Zealand White
Sex:
male
Details on test animals and environmental conditions:
Animals weighed 2.5 to 3.5 kg.
Type of coverage:
occlusive
Vehicle:
not specified
Details on dermal exposure:
The fur is removed from the entire trunk by clipping, and the dose is retained beneath an impervious plastic film. Dosages greater than 20ml/kg cannot be applied in contact with the skin.
Duration of exposure:
Animals are immobolized during the 24-hour contact period, after which the film is removed and the rabbits are caged for subsequent 14-day observation period.
Doses:
0.33 to 2.35
No. of animals per sex per dose:
four
Control animals:
not required
Statistics:
The LD50 and its fidutial range are estimated by the method of Thompson (Thompson WR: Use of moving Averages and Interpolation to Estimate Median effective dose. Bacteriol. Rev. 11: 115, 1947) using the Tables of Weil (Weil, GS: Tables for convenient calculation of Median-effective Dose (LD50 or ED50) and Instructions in their use. Biometrics 8: 249, 1952). The (dose) figures in parntheses show limits of +/- 1.96 standard deviations
Key result
Sex:
male
Dose descriptor:
LD50
Effect level:
>= 880 mg/kg bw
Based on:
test mat.
Remarks on result:
no indication of skin irritation up to the relevant limit dose level
Mortality:
Not described
Clinical signs:
Not described
Body weight:
Initial body weight range: 2.5 to 3.5 kg
Gross pathology:
Not mentioned
Interpretation of results:
Category 3 based on GHS criteria
Remarks:
Note: substance has a harmonized classification as Cat 4
Conclusions:
The LD50 was 880 mg/kg in NewZealand male albino rabbits in a 24 hour exposure (occlusive) based on acceptable scientific methods (Draize method for experimental procedures and Thompson's method for LD50 calculations).
Executive summary:

LD50 was calculated to be 880 mg/kg in NewZealand male albino rabbits exposed to 1 -naphthol for 24 hours (occlusive), follwed by a 14-day observation period. Acceptable scientific methods (Draize method for experimental procedures and Thompson's method for LD50 calculations) were used.

Under the conditions of this study, based on the results, this substance is classified as Acute toxicity - dermal, Category 3 according to the UN GHS criteria.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
Value:
880 mg/kg bw
Quality of whole database:
Klimisch 2

Additional information

Justification for classification or non-classification

On the basis of the data, the 1-naphthol is classified Acute Tox Cat 4, H302 (oral) and Acute tox Cat 3 (dermal), and STOT SE Cat. 3 for inhalation exposure, and STOT SE Category 2 (H371) for oral exposure according to the UN GHS. However, with regard to the dermal classification, there is a harmonized classification of Acute tox Cat 4 (dermal).