Dibutyltin oxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 4-18, 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

not specified

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dibutyltin oxide

EC Number:

212-449-1

EC Name:

Dibutyltin oxide

Cas Number:

818-08-6

Molecular formula:

C8H18OSn

IUPAC Name:

dibutylstannanone

Details on test material:

- Name of test material (as cited in study report): Dibutyltin Oxide

- Physical state: White Powder
- Analytical purity: 98.5%
- Lot/batch No.: EKRDX-052M
- Expiration date of the lot/batch: Feb 28, 1995
- Storage Conditions: Room Temperature

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hazleton Research Products, Inc. , Denver, Pennsylvania
- Age at study initiation: Young adult
- Weight at study initiation: 3142 to 3482 grams
- Housing: Individual suspended wire-mesh cages at the WIL Research Laboratories
- Diet (e.g. ad libitum): Ad libitum, Purina Certified Rabbit Chow #5322
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: Seven days
- Method of Identification: Eartag

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 22 °C
- Humidity (%): 32-70%
- Photoperiod (hrs dark / hrs light): 12 hours light/12 hours dark

Test system

Type of coverage:

other: The 3- and 60-minute exposures were occluded for the corrosion study, and the four-hour exposure was semi-occluded for the irritation study

Preparation of test site:

shaved

Vehicle:

water

Remarks:

For the 3- and 60-minute exposures, materials were not be moistened with water, but for the 4 hour exposure, the solid materials were moistened with deionized water

Controls:

not specified

Amount / concentration applied:

For the 3- and 60-minute exposures, 0.5 grams/site
For the 4-hour exposure, 0.5 grams/site

Duration of treatment / exposure:

Three treatments:
3-minute exposure
60-minute exposure
4-hour exposure

Observation period:

3-minute exposure: 24 and 48 hours after dosing
60-minute exposure: 24 and 48 hours after dosing
4-hour exposure: 30 minutes, 60 minutes, 24, 48, and 72 hours after dosing, and daily thereafter through day 14

Number of animals:

Six

Details on study design:

TEST SITE
- Area of exposure: Dermal surface of shaved backs and flanks
- % coverage: 2.5 cm x 2.5 cm gauze patch
- Type of wrap if used: Patches were overwrapped with plastic wrap for the 3- and 6-minute occluded exposures and gauze bandaging for the four-hour semi-occluded exposure. Bandaging materials were secured with Dermiform Tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Sites were wiped with disposable paper towels moistened with tepid tap water
- Time after start of exposure: Either 3-minutes, 60-minutes, of 4 hours after exposure.

SCORING SYSTEM: Draize method (Table 3)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

1.83

Max. score:

2

Reversibility:

not fully reversible within: 14 days

Results 2

Irritation parameter:

erythema score

Basis:

mean

Time point:

48 h

Score:

1.67

Max. score:

2

Reversibility:

not fully reversible within: 14 days

Results 3

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Score:

1.83

Max. score:

2

Reversibility:

not fully reversible within: 14 days

Results 4

Irritation parameter:

erythema score

Basis:

mean

Time point:

14 d

Score:

1.83

Max. score:

2

Reversibility:

not fully reversible within: 14 days

Remarks on result:

other: disquamination was seen in all rabbits

Results 5

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 72 hours

Results 6

Irritation parameter:

edema score

Basis:

mean

Time point:

48 h

Score:

0.17

Max. score:

1

Reversibility:

fully reversible within: 72 hours

Results 7

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Score:

0

Max. score:

0

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

There was no evidence of corrosion following the three-minute, sixty-minute and four-hour exposures. Dermal irritation following the four-hour exposure included very slight to moderate erythema, very slight to slight edema and desquamation on all sites. All edema completely subsided within 72 hours of application. Very slight to slight erythema persisted through day 14 for all sites.

Other effects:

There was no evidence of corrosion following the 3- and 60-minute and 4-hour exposures to the test material. No irritation greater than very slight to slight erythema and no edema was observed on any three or 60-minute exposure site at both 24 and 48 hours post-exposure.

The test material induced very slight to moderate erythema and very slight to slight edema on all rabbits following the four-hour exposure. All sites had desquamation by day 11. There were no other dermal findings. Edema completely subsisted within 72 hours. Very slight to slight erythema was present on all sites at study termination (day 14).

Any other information on results incl. tables

There was no evidence of corrosion following the three- and 60- minute and 4-hour exposures to the test material. No irritation greater than very slight to slight erythema and no edema was observed on any three or 60 -minute exposure site at both 24 and 4 hours post-exposure.

The test material induced very slight to moderate erythema and very slight to slight edema on all rabbits following the four-hour exposure- All sites had desquamation by day 11. There were no other dermal. findings. Edema completely subsided within 72 hours. Very slight to slight erythema was present on all sites at study termination (day l4).

There were no deaths or significant body weight changes during the study period.

See attached tables for results.

Applicant's summary and conclusion

Interpretation of results:

other: Skin irritant (category 2) according to EU criteria

Conclusions:

There were no deaths or significant body weight changes during the study period. There was no evidence of corrosion following the 3-minute, 60-minute, and 4-hour exposures. Dermal irritation following the 4-hour exposure included very slight to moderate erythema, very slight to slight edema and desquamation on all sites. All edema completely subsided within 72 hours of application. Very slight to slight erythema persisted through day 14 for all sites.

Executive summary:

Dibutyltin oxide was evaluated for dermal irritation on New Zealand White rabbits.

Single 0.5 g doses of the test material were applied to the shaved, intact skin of 6 albino rabbits under occlusive dressings for three and 60 -minute application sites and under semi-occlusive dressings for a four-hour expsoure period. The three and 60 minute application sites were observed immediately after bandage removal and at approximately 24 and 48 hours after dosing for the presence or absence of corrosion. The four hour exposure sites were washed immediately following bandage removal.

There were no deaths or significant body weight changes during the study period. There was no evidence of corrosion following the three-minute, sixty-minute and four-hour exposures. Dermal irritation following the four-hour exposure included very slight to moderate erythema, very slight to slight edema and desquamation on all sites. All edemas completely subsided within 72 hours of application. Very slight to slight erythema persisted through day 14 for all four-hour sites. Based on the data, dibutyltin oxide was found to be non-corrosive when applied under occlusion to the shaved, intact skin of albino rabbits for up to 4 hours.