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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1983
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions

Data source

Reference
Reference Type:
publication
Title:
Concentration-dependent elicitation of dermal sensitization in guinea pigs treated with 2,4-toluene diisocyanate
Author:
Koschier, F.J., Burden, E. J., Brunkhorst, C.S., Friedman, M.A.
Year:
1983
Bibliographic source:
Toxicol. Appl. Pharmacol., 67, 401-407

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
not specified
Principles of method if other than guideline:
not applicable
GLP compliance:
not specified
Type of study:
open epicutaneous test
Justification for non-LLNA method:
Other study available.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
dibutyl ether (purity not indicated)

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
not specified
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: commercial breeder
- Age at study initiation: young adults
- Housing: Animals were housed individually in stainless steel cages with wire mesh bottoms
- Diet (e.g. ad libitum): certified guinea pig chow 5026 (ralson Purina Co.) was available ad libitum
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2°C
- Humidity (%): 40 - 60%
- Photoperiod (hrs dark / hrs light): 12 hours each cycle

Study design: in vivo (non-LLNA)

Induction
Route:
epicutaneous, open
Vehicle:
other: no vehicle used
Concentration / amount:
The animals received a total application of 50 µl dibutyl ether with each animal receiving two 25 µl amounts on separate sites
Challenge
Route:
epicutaneous, open
Vehicle:
other: no vehicle used
Concentration / amount:
The animals received a total application of 50 µl dibutyl ether with each animal receiving two 25 µl amounts on separate sites
No. of animals per dose:
5
Details on study design:
1st application: Induction 50 µl other: two 25 µl applications undiluted open epicutaneous
2nd application: Challenge 150 µl other: six 25 µl applications undiluted open epicutaneous
3rd application: Challenge 150 µl other: six 25 µl applications undiluted open epicutaneous

Young adult guinea pigs (strain Hartley, received from commercial breeders) were housed individually in stainless-steel cages with wire-mesh bottoms in temperature (21 ± 2 °C) and humidity-controlled (40 - 60 %) rooms. Twelve hours of continuous fluorescent lighting was provided daily. Certified guinea pig chow 5026 (Ralson Purina Co.) and water were available ad libitum. The hair on the dorsum was clipped 24 hours before exposure. For induction, the animals received a total application of 50 µl undiluted dibutyl ether with each animal receiving two 25 µl amounts on separate sites. Five days later, each guinea pig received on virgin sites six challenge applications of 25 µl undiluted aliquots. A rechallenge was performed 9 days after the first challenge. Skin reaction was scored by the method of Draize at 24 and 48 hours after application
Challenge controls:
no information available
Positive control substance(s):
no

Results and discussion

Positive control results:
None

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
25 µl of the undlluted test substance
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
25 µl of the undliuted test substance
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
rechallenge
Hours after challenge:
24
Group:
test group
Dose level:
25 µl of the undliluted test substance
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
rechallenge
Hours after challenge:
48
Group:
test group
Dose level:
25 µl of the undliluted test substance
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Key result
Group:
positive control
Remarks on result:
not measured/tested
Group:
negative control
Remarks on result:
not measured/tested

Any other information on results incl. tables

The animals did not respond with dermal hypersensitivity reactions when challenged with dibutyl ether. The mean scores 24 hours after day 5 and day 14 challenge were 0.8 and 0.0, respectively. No individual scores were greater than 1.0 (maximum possible score of 8). According to these results, dibutyl ether has no sensitization potency.

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Under the conditions of the study, the animals did not respond with dermal hypersensitivity reactions when challenged with dibutyl ether. The mean scores 24 hours after day 5 and day 14 challenge were 0.8 and 0.0, respectively. No individual scores were greater than 1.0 (maximum possible score of 8). According to these results, dibutyl ether has no sensitization potency.
Executive summary:

The skin sensitization potential of dibutyl ether was evaluated in guinea pigs. Young adult guinea pigs (strain Hartley, received from commercial breeders) were housed individually in stainless-steel cages with wire-mesh bottoms in temperature (21 ± 2 °C) and humidity-controlled (40 - 60 %) rooms. Twelve hours of continuous fluorescent lighting was provided daily. Certified guinea pig chow 5026 (Ralson Purina Co.) and water were available ad libitum. The hair on the dorsum was clipped 24 hours before exposure. For induction, the animals received a total application of 50 µl undiluted dibutyl ether with each animal receiving two 25 µl amounts on separate sites. Five days later, each guinea pig received on virgin sites six challenge applications of 25 µl undiluted aliquots. A rechallenge was performed 9 days after the first challenge. Skin reaction was scored by the method of Draize at 24 and 48 hours after application. Under the conditions of the study, the animals did not respond with dermal hypersensitivity reactions when challenged with dibutyl ether. The mean scores 24 hours after day 5 and day 14 challenge were 0.8 and 0.0, respectively. No individual scores were greater than 1.0 (maximum possible score of 8). According to these results, dibutyl ether has no sensitization potency.