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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:
No data
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
OECD Guide-line 406 "Skin Sensitisation" method (Buehler test ) was performed before the LLNA was set as preferred test method.

Test material

Constituent 1
Chemical structure
Reference substance name:
Boric acid
EC Number:
233-139-2
EC Name:
Boric acid
Cas Number:
10043-35-3
Molecular formula:
H3BO3
IUPAC Name:
Boric acid
Details on test material:
- Name of test material: Boric acid
- Physical state: White powder
- Analytical purity: >99%
- Lot/batch No.: 4H25-3611

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Davidson’s Mill Farms, South Brunswick, NJ
- Age at study initiation: Young adult
- Weight at study initiation: Males: 314 -411 g; females: 282-376 g

Study design: in vivo (non-LLNA)

Induction
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
Induction: 0.4 g 95 % w/w boric acid
Challenge: 95 % w/w boric acid
Challenge
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
Induction: 0.4 g 95 % w/w boric acid
Challenge: 95 % w/w boric acid
No. of animals per dose:
Test Group: 20 animals
Naive Control: 10 animals
Positive Control: 20 animals
Positive Naive Control: 10 animals
Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Concentrations: 0.4 g 95 % w/w boric acid moistened with distilled water to enhance skin contact.


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: Day 28
- Exposure period: Test substance was wiped off with water after 6 h.
Challenge controls:
No data
Positive control substance(s):
yes
Remarks:
Dinitrochlorobenzene

Results and discussion

Positive control results:
No data

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.4 g 95% w/w/boric acid
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
Very faint erythema seen in one animal at induction stage and 2 animals at challenge stage and also in one naïve control. No other adverse effect observed
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
0.4 g 95% w/w/boric acid
No. with + reactions:
0
Total no. in group:
20
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
no data
No. with + reactions:
10
Total no. in group:
20
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
no data
No. with + reactions:
7
Total no. in group:
20
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0
No. with + reactions:
0
Total no. in group:
20
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
0
No. with + reactions:
0
Total no. in group:
20

Any other information on results incl. tables

Observations:

Treatments

Buehler test

Observations/Remarks

 

Day of treatment

 

Induction 1

day 0

Very faint erythema (0.5) observed at one test site at 24 hours after first induction dose. No other irritation observed

Induction 2

7

No irritation observed

Induction 3

14

No irritation observed

Challenge

28

No irritation observed

Scoring 1

29

Very faint erythema (0.5) observed at two test sites at 24 hours after  challenge dose. Irritation persisted at one site for 48 hours.  Very faint erythema (0.5) observed at one test site at 24 hours in one naive control.

Scoring 2

30

 

Results of skin sensitisation test:

 

Number of animals with signs of allergic reactions /
number of animals in group

 

Negative control

Test group

Positive control

scored after 24h

0 / 10

0 / 20

10/20

scored after 48h

0 / 10

0 / 20

7/20

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
OECD Guideline 406 "Skin Sensitisation" method (Buehler test ) was performed using 95 % w/w boric acid moistened with distilled water to enhance skin contact. Very faint erythema was observed in one animal at induction stage and 2 animals at challenge stage and also in one naïve control. No other adverse effects were observed therefore the test substance was considered a non-sensitiser.