Registration Dossier

Administrative data

Description of key information

No skin sensitisation was induced by the test substance in a Buehler test with guinea pigs.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records
Reference
Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1 JULI 1988 to 10 AUG 1988
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
No LLNA was performed because a reliable guideline study according to GLP in guinea pigs is available.
Qualifier:
according to
Guideline:
EPA OTS 798.4100 (Skin Sensitisation)
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
valid study from 1988 available which has been conducted as "Buehler Test"
Species:
guinea pig
Strain:
Hartley
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Davidson's Mills Farm, South Brunswick, NJ
- Weight at study initiation: 332-449 g
- Housing: gang-caged
- Diet (ad libitum): Purina guinea pig pellets
- Water (ad libitum): tap water
- Acclimation period: 24 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.8-22.2

Route:
epicutaneous, semiocclusive
Vehicle:
other: 95% ethanol
Concentration / amount:
4% (w/w)
Day(s)/duration:
10 inductions/ 6 h
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
No.:
#1
Route:
epicutaneous, semiocclusive
Vehicle:
other: 95% ethanol
Concentration / amount:
4% (w/w)
Day(s)/duration:
1 d/ 6 h
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
10 animals in the test and positive control
5 naive controls per group
Details on study design:
RANGE FINDING TESTS:
The maximum non-irritating concentration of 4 % was determined in a range-finding test (4 animals in two sets, application of the test substance to the clipped dorsal thoracolumbar region, 4 test sites per animal, 0.5 ml of 1, 2, 4, 6.25, 8, 25 and 50% dilutions of the test substance in 95% ethanol, 6 h of semiocclusive exposure and examination 24 h after initial application)

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 10
- Exposure period: 6 h each
- Test groups: 10 animals
- Control group: 5 naive control animals per group
- Site: clipped dorsal thoracolumbar region
- Duration: 3.5 weeks
- Concentrations: 4%


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 14 days after 10th induction application
- Exposure period: 6 h (not stated in study report, but according to guideline)
- Test groups: 10 animals
- Control group: 5 naive control animals per group
- Site: untreated site on left flank
- Concentrations: 4%
- Evaluation (hr after challenge): 24 and 48 h after challenge
Challenge controls:
5 naive controls per group
Positive control substance(s):
yes
Remarks:
0.08% dinitrochlorobenzene (DNCB) in 95% ethanol
Positive control results:
6/10 test sites were erythematous 24 h after challenge, 4/10 were clear. At the 48 h reading there were 8 sites with erythema and 2 without effect. Scores ranged from 0.5 (very faint, nonconfluent) to 3 (strong). Detailed results are presented in the attached document.
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
4%
No. with + reactions:
2
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 4%. No with. + reactions: 2.0. Total no. in groups: 10.0.
Key result
Reading:
1st reading
Hours after challenge:
48
Group:
test group
Dose level:
4%
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 48.0. Group: test group. Dose level: 4%. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. No with. + reactions: 0.0. Total no. in groups: 5.0.
Reading:
1st reading
Hours after challenge:
48
Group:
negative control
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 48.0. Group: negative control. No with. + reactions: 0.0. Total no. in groups: 5.0.
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
0.08% DNCB
No. with + reactions:
6
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: positive control. Dose level: 0.08% DNCB. No with. + reactions: 6.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
48
Group:
positive control
Dose level:
0.08% DNCB
No. with + reactions:
8
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 48.0. Group: positive control. Dose level: 0.08% DNCB. No with. + reactions: 8.0. Total no. in groups: 10.0.

All animals appeared active and healthy and gained weight during the induction phase and in the period to challenge.

Induction phase: The occurence of generall sporadic and transient very faint non-confluent erythema (score 0.5) was observed during the first two weeks of the induction phase. One animal had eschar at the test site between the 5th and 6th induction treatment which did not re-occur after change of the test site. One animal showed a faint erythema after the 9th induction.

Challenge: Two sites challenged with the test substance showed very faint, non-confluent erythema 24 h after challenge (score 0.5; remaining animals: score 0). No reaction (score 0) was observed in all animals 48 h after application.

Interpretation of results:
GHS criteria not met
Conclusions:
Under the conditions of this study the test substance was not sensitising in a Buehler guinea pig sensitisation test.
Executive summary:

In this study according to EPA guideline 798.4100 a highest non-irritating concentration of a 4% dilution of the test substance (89% purity) in 95% ethanol was determined in a pre-test. 10 young adult male guinea pigs were treated ten times for 6 h each with this concentration during a 3.5 week induction phase. Another group of 10 males were treated equally with the positive control substance (0.08% dinitrochlorobenzene in 95% ethanol).

The occurence of generall sporadic and transient very faint non-confluent erythema was observed during the first two weeks of the induction phase. One animal developed transient eschar at the test site which did not re-occur after change of the test site. One animal showed a faint erythema after the 9th induction.

Challenge: Fourteen days after the last induction a challenge with the same concentration of test substance or the positive control substance was performed at a naive site of each animal and the reaction was scored 24 and 48 h later. 5 animals per each group served as naive controls and were treated with the test material or control material only at challenge. Two animals challenged with the test substance showed very faint, non-confluent erythema 24 h after challenge (Score 0.5, remaining animals: score: 0). No reaction was observed in all animals 48 h after application. Based on these results the test substance was judged to be not sensitising. The positive control substance produced a positive response (Pennwalt/PSL, 1988).

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

In the key study (Buehler test according to EPA guideline 798.4100) a highest non-irritating concentration of 4% of the test substance in 95% ethanol was determined in a pre-test. 10 young adult male guinea pigs were treated ten times for 6 h each with this concentration during a 3.5 week induction phase. Another group of 10 males were treated equally with the positive control substance (0.08% dinitrochlorobenzene in 95% ethanol). Fourteen days after the last induction a challenge with the same concentration of test substance or the positive control substance was performed at a naive site of each animal and the reaction was scored 24 and 48 h later. 5 animals per each group served as naive controls and were treated with the test material or control material only at challenge.

The occurence of generall sporadic and transient very faint non-confluent erythema was observed during the first two weeks of the induction phase. Two animals challenged with the test substance showed very faint, non-confluent erythema 24 h after challenge. No reaction was observed in all animals 48 h after application. Based on these results the test substance was judged to be not sensitising. The positive control substance produced a positive response (Pennwalt/PSL, 1988).

Sidorin et al. (1984) confirmed these results, but no experimental details are reported. In Patty's Industrial Hygiene and Toxicology (Cavender, 2001) the substance was reported to be sensitising, but this is based only on general annotations in two manufacturer's catalogues which are not substantiated by any experimental data. It is therefore concluded that this information is not reliable and can be disregarded in view of the unequivocal results of the key study.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

With respect to the negative findings in the key study on skin sensitisation no classification according to Regulation (EC) No 1272/2008 is required.