Cesium acetate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From Jan 9, 1997 to Jan 24, 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA Pesticide Assessment Guidelines, Subdivision F (81-1) EPA Health Effects Testing Guidelines (TSCA Guideline No. 798.1100)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

other: Limit test

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cesium acetate

EC Number:

222-248-0

EC Name:

Cesium acetate

Cas Number:

3396-11-0

Molecular formula:

C2H4O2.Cs

IUPAC Name:

cesium acetate

Test material form:

liquid

Remarks:

Cloudy

Details on test material:

- Name of test material (as cited in study report): Cesium acetate
- Physical state: A cloudy liquid
- Storage condition of test material: Room temperature

Test animals

Species:

rabbit

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Naive, young adult male and female Sprague-Dawley New Zealand White rabbits weighing 2405 to 2652 g were used. The animals were purchase from a vendor who equals or exceeds U.S.D.A. standards even though rats are not regulated animals. All animals were acclimated to the laboratory for at least 5 d before being used. Animals were housed singly in wire mesh suspension cages and were supplied Teklad Hi-Fiber Rabbit Diet and tap water ad libitum during both acclimation and test periods. The animal room was maintained on a 12 h light/12 h dark cycle and at a temperature of 61-72°F and a relative humidity of 30-70%. There were no contaminants in either the feed or the water that were expected to affect the outcome of this study.

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

On the day prior to dosing, the hair of each rabbit was clipped from the dorsal surface of the trunk using an electric clipper so as to expose not less than 10% of the body surface area. Care was taken to avoid abrading the skin, which would alter its permeability. Animals were weighed shortly before test substance exposure in order to calculate doses. Using the bulk density of the test substance to determine the volume for dosing, the undiluted test substance at a dosage of 5000 mg/kg bw was applied uniformly to the dorsal surface of the animal. The test substance was held in contact with the skin by wrapping gauze around the trunk of each animal and securing with paper tape. The test site was further covered with a sleeve of rubber dental dam to retain the gauze dressing and test substance and ensure that the animals could not ingest the test substance. Each rabbit was then fitted with an Elizabethan collar to prevent the removal of the wrapping. At the end of an approx. 24 h exposure period, the Elizabethan collar and wrapping were removed, and any unabsorbed test substance remaining on the skin was removed by gentle sponging using a towel moistened with tap water. The presence or absence of residual test substance on the wrapping and on the rabbits were documented.

Duration of exposure:

24 h

Doses:

Single dose of 5000 mg/kg bw of the test substance

No. of animals per sex per dose:

Ten animals (five/sex)

Control animals:

not required

Details on study design:

Animals were observed for signs of toxicity and behavioral changes once, or more frequently if clinical signs were present, on the day of test substance administration. All surviving rabbits were maintained for 14 d following completion of the exposure period. An examination of gross signs of toxicity was carried out once daily with an additional check for viability during the day. Skin reactions and other evidence of irritation or injury including erythema, edema, atonia, desquamation, necrosis, coriaceousness, and fissuring were noted once daily.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was noted as of Day 14 following the test substance administration.

Clinical signs:

other: The only clinical sign noted during the observation period was fecal stains.

Gross pathology:

Gross necropsy fIndings for animals that survived during the observation period included liver pale, liver mottled, kidneys pale, and kidneys congested.

Applicant's summary and conclusion

Conclusions:

Under the study condition, the dermal LD50 of the test substance in rats was > 5000 mg/kg bw.

Executive summary:

A study was conducted to assess the acute dermal toxicity of the test substance according to OECD Guideline 402 and EPA Pesticide Assessment Guidelines, Subdivision F (81-1) EPA Health Effects Testing Guidelines (TSCA Guideline No. 798.1100), in compliance with GLP. The substance was dermally administered undiluted to five male and five female rabbits at a dose level of 5000 mg/kg bw. The animals were then observed for 14 d. No mortality was recorded and the only clinical sign noted was faecal staining. Irritation effects seen during the observation period included moderate to extreme erythema, mild or slight to marked edema, mild or slight to moderate desquamation, mild or slight coriaceousness, necrosis, blanching, scabbing, purple discoloration and dark brown discoloration. All animals exhibited an increase in bodyweight by Day 14. Gross necropsy findings in animals which survived until termination included pale, mottled or congested livers and pale kidneys. Under the study condition, the dermal LD50 of the test substance in rats was > 5000 mg/kg bw (Harrod, 1997).