Calcium acetylide

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Guideline study with acceptable restrictions performed with the relevant decomposition product Ca(OH)2; Minor devaitions from the guideline with no effect on the study results: - The purity and the stability of the test substance are missing. - According to the guideline, body weights of the animals during the observation period should be determined, which is missing in this report.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

yes

Remarks:

, see "rationale for reliabiility"

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

, see "rationale for reliabiility"

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

7719-01-9

Cas Number:

7719-01-9

IUPAC Name:

7719-01-9

Constituent 2

Reference substance name:

Calcium dihydroxide

EC Number:

215-137-3

EC Name:

Calcium dihydroxide

Cas Number:

1305-62-0

Molecular formula:

CaH2O2

IUPAC Name:

calcium dihydroxide

Test material form:

semi-solid (amorphous): gel

Remarks:

migrated information: paste

Details on test material:

- Name of test material (as cited in study report): "Weisskalkteig" (from the Federal German Lime Industry Association in Cologne), which is generally known as a paste-like mixture of Calcium dihydroxide with water (white lime paste).
No further information on the test substance was stated.

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Germany, External branch
- Weight at study initiation: 2.4 to 2.9 kg
- Housing: Individual cages
- Diet (ad libitum): Commercially available complete feed
- Water (ad libitum)
- Acclimation period: one week

ENVIRONMENTAL CONDITIONS
- Temperature: 21 +/- 2 °C
No further information on the test animals was given.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Remarks:

The test item "Weisskalkteig" is most appropriately translated as "white lime paste". As such it is an aqeous paste-like preparation and does not require further moistening in order to ensure good skin contact.

Details on dermal exposure:

TEST SITE
- Area of exposure: On the day before the test sample was applied to the rabbits, the fur on their skin was sheared over an area of some 8 cm wide and 15 cm long. The test sample was applied evenly with a plastic spatula on an area of 100 cm^2 of shorn skin.
- Type of wrap if used: The treated skin area was covered with a gauze. The gauze was affixed using a "Peha-haft" dressing, so that the animal could not strip off the gauze.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The treated skin area was rinsed with water.
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): A quantity of 2.5 g/kg of body weight
No further infomration on dermal exposure was stated.

Duration of exposure:

24 hours

Doses:

2500 mg/kg

No. of animals per sex per dose:

5 males / 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days (including treatment day)
- Frequency of observations and weighing: The animals were clinically examined on a daily basis.
- Necropsy of survivors performed: Yes
On the last day of the observation phase, the rabbits were put down byintravenous injection of Pentobarbital (Nembutal R), and then immediately dissected in the Institute of Pathology, of the Hannover College of Veterinary Medicine.
- Other examinations performed: During the daily clinical observations, the general conditions were observed plus changes that occurred in the area of the fur and the treated skin, the eyes and the mucous membranes were registered and recorded.
No further information on the study design was stated.

Statistics:

No data

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 500 mg/kg bw

Based on:

test mat.

Mortality:

There were no indications of toxic effects from the test sample after dermal application.

Clinical signs:

other: Overall, redness, followed by scabbing, did occur in the area of the treated skin after the dressing was removed and the skin was cleaned. Slight redness after removal of the dressing was observed in one female rabbit. Moderate redness plus scabbing was o

Gross pathology:

Dissection of the rabbits yielded no particular results.

Other findings:

- Histopathology: The pathological-histological examination of the liver, kidneys, lung and skin yielded no particular results.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The available data showed that the tested White lime paste caused no acute toxic effect after dermal application. However, the test did show skin irritating effects from the test sample.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified.

Executive summary:

In an acute dermal toxicity study according to OECD TG 402, groups of 5 New Zealand White rabbits/sex were dermally exposed to Calcium hydroxide in water (White lime paste) for 24 hours to 100 cm² of shorn skin at a dose of 2500 mg/kg. Animals were then observed for 14 days.

There were no treatment related deaths or necropsy signs. Clinical signs included redness, followed by scabbing, occuring in the area of the treated skin after the dressing was removed and the skin was cleaned. Slight redness after removal of the dressing was observed in one female rabbit.

Moderate redness plus scabbing was observed after removal of the dressing in four females rabbits and three male rabbits. Moderate redness plus pronounced scabbing was observed after removal of the dressing in one male rabbit. The pathological-histological examination of the liver, kidneys, lung and skin yielded no particular results.

Based on these results, GHS criteria are not met and classification is not warranted according to Regulation (EC) No. 1272/2008.