Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
22 February 1985 to 19 April 1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
Split adjuvant test

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985
Report date:
1985

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
12 May 1981
Principles of method if other than guideline:
Split Adjuvant Test, challenge concentration is similar to induction concentration (non-irritant concentration)
GLP compliance:
yes
Type of study:
split adjuvant test
Justification for non-LLNA method:
Reliable data that were available before the LLNA study was introduced

Test material

Constituent 1
Chemical structure
Reference substance name:
5-methyl-s-triazolo[1,5-a]pyrimidin-7-ol
EC Number:
219-706-7
EC Name:
5-methyl-s-triazolo[1,5-a]pyrimidin-7-ol
Cas Number:
2503-56-2
Molecular formula:
C6H6N4O
IUPAC Name:
5-methyl-s-triazolo[1,5-a]pyrimidin-7-ol
Test material form:
solid: particulate/powder
Specific details on test material used for the study:
induction 25% in petrolatum; challenge 25% in petrolatum (non-irritant)

In vivo test system

Test animals

Species:
guinea pig
Strain:
Dunkin-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Olac, Bicester, UK
- Females (if applicable) nulliparous and non-pregnant: not specified
- Age at study initiation: adult
- Weight at study initiation: 454-567 g
- Housing: 2/cage; in cages with wire-mesh floors
- Diet: standard guinea-pig diet (LC 23-B, Hope Farms, Woerden) ad libitum
- Water: tap water ad libitum
- Acclimation period: 27 days
- Indication of any skin lesions: not indicated (prevented by wrapping the back paws of the animals)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.5-21 °C
- Humidity (%): 50-65%
- Air changes (per hr): not indicated
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Induction
Route:
epicutaneous, occlusive
Vehicle:
petrolatum
Concentration / amount:
0.2 mL of 25% substance in petrolatum
Day(s)/duration:
9 days (repeated exposure for 4 periods of 48-72 hours) until day 9
Adequacy of induction:
other: non-irritant concentration, adequacy not assessed
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
petrolatum
Concentration / amount:
0.1 mL of 25% substance in petrolatum
Day(s)/duration:
24 hours
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
20 treated and 10 controls
Details on study design:
RANGE FINDING TESTS: PIT (4 animals) was performed after the induction to make sure that the challenge concentration was non irriitant

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 4 times
- Exposure period: 48-72 h
- Test groups: yes
- Control group: not exposed (Freund complete adjuvant on day 4)
- Site: back (2x2cm)
- Frequency of applications: every 2 days (day 0, 2, 4 and 7)
- Duration: 48-72 h
- Concentrations: 0.2 mL at 25%
- Adjuvant: 0.1 mLFreund's complete adjuvant on day 4 intra-dermal (back)

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: day 20
- Exposure period: 24 h
- Test groups: yes
- Control group: yes
- Site: flank
- Concentrations: 0.1 mL at 25%
- Evaluation (hr after challenge): 24 and 48 hours after exposure
Challenge controls:
with 0.1 mL of 25% substance in petrolatum
Positive control substance(s):
no

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.1 mL 25%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
all animals appeared healthy and were feeding normally
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.1 mL 25%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
all animals appeared healthy and were feeding normally
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
0.1 mL 25%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
all animals appeared healthy and were feeding normally
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
0.1 mL 25%
No. with + reactions:
1
Total no. in group:
20
Clinical observations:
all animals appeared healthy and were feeding normally
Group:
positive control
Remarks on result:
not measured/tested

Any other information on results incl. tables

no effects on body weight gain were seen

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The substance is not sensitizing to the skin
Executive summary:

Female guinea-pigs (20 in test group and 10 in controls) were induced epicutaneously with the test substance (25% in petrolatum under occlusion) over a 9 day period in a Split Adjuvant test. On day 20 of the study the animals were challenged with 25% substance in petrolatum for a 24 hour period. The reaction of the exposed skin was assessed at 24 and 48 hours after the challenge period. None of the animals showed any signs of sensitization. Therefore it is concluded that the substance is not sensitizing to the skin.