Bentonite, acid-leached

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Performed between 23 March 2010 and 06 April 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to GLP and internationally accepted guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Bentonite, acid-leached

EC Number:

274-324-8

EC Name:

Bentonite, acid-leached

Cas Number:

70131-50-9

Molecular formula:

unspecified for this UVCB substance

IUPAC Name:

Bentonite, acid-leached

Details on test material:

- Name of test material (as cited in study report):Bentonite acid-leached
- Physical state: Solid
- Lot/batch No.: not supplied
- Expiration date of the lot/batch: 31 December 2010
- Storage condition of test material: Room temperature in the dark

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Limited, Bicester, Oxon, UK
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: At least 200 g
- Housing: Suspended solid-floor polypropylene cages furnished with woodflakes
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: At lesat 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 19 to 25 °C
- Humidity: 30 to 70 %
- Air changes: 15 changes per hour
- Photoperiod: 12 hrs dark /12 hrs light

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
Test material was applied to an area of shorn skin (approximately 10% of the total body surface). A piece of surgical gauze was placed over the treatment area and semi-occ;luded with a piece of self-adhesive bandage.

REMOVAL OF TEST SUBSTANCE
Cotton wool moistened with distilled water was used to remove any residual test material

TEST MATERIAL
The test material was applied at a dose level of 2000 mg/kg

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

5/sex/dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for deaths or overt signs of toxicity 1/2, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days. Bodyweight was recorded on day 0, 7 and 14.
- Necropsy of survivors performed: yes, this consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths

Clinical signs:

other: There were no signs of systemic toxicity

Gross pathology:

No abnormalities were noted.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute dermal median lethal dose (LD50) of the test material was > 2000 mg/kg bw. The test material is therefore not classified for acute dermal toxicity in accordance with Regulation (EC) No 1272/2008