Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2016-2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report date:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Version / remarks:
1987
Qualifier:
according to guideline
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Version / remarks:
30 May 2008
GLP compliance:
yes (incl. QA statement)
Test type:
standard acute method
Limit test:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
2,6-di-tert-butyl-4-nonylphenol
EC Number:
224-320-7
EC Name:
2,6-di-tert-butyl-4-nonylphenol
Cas Number:
4306-88-1
Molecular formula:
C23H40O
IUPAC Name:
2,6-di-tert-butyl-4-nonylphenol
Test material form:
liquid
Details on test material:
- Density: 0.895 g/cm3
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No. of test material: Delivered by the sponsor; Batch: 222375101
- Expiration date of the lot/batch: 02 May 2018
- Purity test date: 02 September 2016
-Arrival of the Test item: 13 September 2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions:


Test animals

Species:
rat
Strain:
other: WISTAR Crl: WI(Han)
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany. The animals were derived from a control full-barrier maintained breeding system (SPF).
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation:
Males: 7-8 weeks old
Females: 8-9 weeks old
- Weight on the day of administration:
Males: 246 – 253 g
Females: 214 – 219 g
- Fasting period before study: No
- Housing: The animals were kept individually in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding.
- Diet (e.g. ad libitum): Free access to Altromin 1342 maintenance diet for rats and mice.
- Water (e.g. ad libitum): Free access to tap water, sulphur acidified to a pH value of approximately 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals).
- Acclimation period: at least five days under laboratory conditions

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- Humidity (%): 55 ± 10%
- Air changes (per hr): 10x/hour
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES:
From: Experimental starting date: 18 January 2017
To: Experimental Completion Date: 02 February 2017

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
TEST SITE
- Area of exposure: dorsal area of the trunk
- % coverage: No less than 10% of the body surface
- Type of wrap if used: . Thie dressing consisted of a semi-occlusive dressing made of a porous gauze and non-irritating tape and was fixed with an additional dressing in a suitable manner.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): At the end of the exposure period the residual test item was removed using aqua ad injectionem.
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg body weight



Duration of exposure:
24 hours
Doses:
2000 mg/kg body weight
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
The animals were weighed on day 1 (prior to application) and on days 8 and 15.
A careful clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). As soon as symptoms were noticed they were recorded. Thereafter, the animals were observed for clinical signs once daily until the end of the observation period. All abnormalities were recorded.
Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, autonomic and central nervous systems and somatomotor activity and behaviour pattern were examined. Attention was directed to observations of tremors, convulsions, salivation, diarrhea, lethargy, sleep and coma.
- Necropsy of survivors performed: yes. At the end of the observation period the animals were sacrificed with an overdosage of pentobarbital injected intraperitoneally at a dosage of 250 – 400 mg/kg bw.
All animals were subjected to gross necropsy and examined macroscopically for gross pathological changes. In absence of gross pathological changes no tissues were preserved for a possible histopathological evaluation.

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
No deaths.
Clinical signs:
No treatment-related effects were observed.
No erythema or oedema was observed. Scratches were observed in 1 of 5 male and 2 of 5 female animals.
All signs of irritation were reversible within the observation period.
Body weight:
The body weight development of all male and female animals was within the expected range.

Gross pathology:
No specific gross pathological changes were recorded for any animal.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Under the conditions of the present study, single dermal application of the test item 2,6-Di-tert-butyl-4-nonylphenol to rats at a dose of 2000 mg/kg body weight was not associated with mortality and there were no signs of toxicity but slight signs of irritation.The dermal LD50 was determined to be >2000 mg 2,6-Di-tert-butyl-4-nonylphenol /kg body weight
Executive summary:

5 Male and 5 female WISTAR Crl: WI(Han) rats were tested for acute dermal toxicity according to OECD TG 402.

Approximately 24 hours before the test, the fur was removed from the dorsal area of the trunk using an electric clipper. Care was taken to avoid abrading the skin, and only animals with healthy intact skin were used. No less than 10% of the body surface was cleared for the application. Prior to application a detailed clinical observation was made of all animals. Only healthy animals were used.

The test item was applied at a single dose, uniformly over an area which was approximately 10% of the total body surface.

The test item was held in contact with the skin by a dressing throughout a 24-hour period. This consisted of a semi-occlusive dressing made of a porous gauze and non-irritating tape and was fixed with an additional dressing in a suitable manner. The test item was applied undiluted at a single dose of 2000 mg/kg body weight to each animal. The test item was held in contact with the skin throughout a 24-hour period. At the end of the exposure period the residual test item was removed using aqua ad injectionem.

All animals were observed for 14 days after dosing. Signs of erythema and oedema were assessed using the scoring system laid down in OECD 404. The animals were weighed on day 1 (prior to application) and on days 8 and 15. A careful clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). As soon as symptoms were noticed they were recorded. Thereafter, the animals were observed for clinical signs once daily until the end of the observation period. All abnormalities were recorded. Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, autonomic and central nervous systems and somatomotor activity and behaviour pattern were examined. Attention was directed to observations of tremors, convulsions, salivation, diarrhea, lethargy, sleep and coma.

At the end of the observation period the animals were sacrificed with an overdosage of pentobarbital injected intraperitoneally at a dosage of 250 – 400 mg/kg bw. All animals were subjected to gross necropsy and examined macroscopically for gross pathological changes. In absence of gross pathological changes no tissues were preserved for a possible histopathological evaluation.

The test item showed no mortality, no signs of acute dermal toxicity but slight signs of dermal irritation after a single dose application.

The body weight development of all male and female animals was within the expected range.

No specific gross pathological changes were recorded for any animal.

Under the conditions of the present study, single dermal application of the test item 2,6-Di-tert-butyl-4-nonylphenol to rats at a dose of 2000 mg/kg body weight was not associated with mortality and there were no signs of toxicity but slight signs of irritation. The dermal LD50 was determined to be >2000 mg 2,6-Di-tert-butyl-4-nonylphenol /kg body weight.