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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Remarks:
in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
17 Nov 1979 - 31 Dec 1979
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:
1981
Report Date:
1981

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
An intradermal sensitization test was conducted by injecting nitroethane solution (P-1355) into male guinea pigs according to Landsteiner and Jacobs procedure (Landsteiner, K., and J. Jacobs. "Studies on Sensitization of Animals with Simple Chemical Compounds. J. Exp. Med. 61:643-656, 1935).
GLP compliance:
no
Type of study:
other: Landsteiner and Jacobs
Justification for non-LLNA method:
This study was conducted before the LLNA method became available,

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
The test material consisted of 97.70% nitroethane, 0.13% nitromethane, 1.80% 2-nitropropane and 0.024% water.

In vivo test system

Test animals

Species:
guinea pig
Strain:
not specified
Sex:
male
Details on test animals and environmental conditions:
Thirty male guinea pigs weighing 250 to 300 g were divided into three groups of 10 each. The animals' backs and flanks were shaved free of hair.

Results and discussion

Positive control results:
In the positive control (Group II) at 24 h, eight animals with 0.03% and ten animals with 0.3% solution of DNCB showed skin reactions. At 48 hours all the animals challenged with 0.3% DNCB solution showed skin reactions.

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
1% test substance
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
1% test substance
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
0.3% DNCB
No. with + reactions:
10
Total no. in group:
10
Remarks on result:
positive indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
0.3% DNCB
No. with + reactions:
10
Total no. in group:
10
Remarks on result:
positive indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.9% saline, challenge with 1% of test substance
No. with + reactions:
2
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
0.9% saline, challenge with 1% of test substance
No. with + reactions:
1
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation

Any other information on results incl. tables

During the induction phase the guinea pigs in Group I showed some skin reactions when injected with 10% (first two injections) and 5% (third injection) solution, so the last seven injections were made with a 1% solution of P-1355. None of the animals in Group III showed any skin reactions. The animals in Group II showed mild to necrotic skin reactions during the entire induction period. At challenge, Group I (treatment group) and Group III (negative control) guinea pigs were intradermally injected with 1.0% solution of P-1355, and none of the animals in Group I showed any skin reactions, but two animals at 24 h and one animal at 48 h in Group III showed mild reactions.

Table 1 P-1355 Intradermal Sensitization Challenge Skin Reactions Scores in Guinea Pigs

 Description

 Group I

Test Material   

      Group II

Positive Control    

  Group III

Negative Control              

 Material injected  P-1355              DNCB      Saline
 Number of animals  10     10     

10

 Induction dose % conc.

 10 to 1   

0.3

 0.9

 Challenge material

P-1355

DNCB

  P-135

 DNCB 

 % Conc./site

 1

  0.3

 0.03

0.3

 0.03

 Reaction scored at (h)

 24

 48

 24

 48

 24

 48

 24

 48

 24

 48

 24

 48

 No. reacted/No. challenged

0/10 

 0/10

 10/10

 10/10

 8/10

 10/10

 2/10

 1/10

 0/10

0/10

 0/10

 0/10

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information
Conclusions:
Nitroethane (P-1355) was a non-sensitiser to the guinea pigs under the conditions of this test. The positive control DNCB gave an expected positive response.
Executive summary:

The dermal sensitization potential of nitroethane was examined using the method of Landsteiner and Jacobs. Nitroethane (P-1355) was a non-sensitiser to the guinea pigs under the conditions of this test. The positive control DNCB gave an expected positive response.