α,α,α-trifluoro-4-nitro-m-cresol

Endpoint summary

Description of key information

Skin:

In a primary skin sensitation study in guinea pigs similar to OECD guideline 406, the test substance showed no skin sensitizing potential (Hazleton Laboratories, 1990).

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:

1990-05-31 to 1990-08-16

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

1992-07-17

Principles of method if other than guideline:

According to Buehler et al., 1980

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

The test was conducted before the implementation of OECD 429 in 2002.

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature

OTHER SPECIFICS: dark brown liquid

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Hazleton Research Products, Inc.
- Microbiological status of animals, when known: SPF
- Age at study initiation: young adult
- Weight at study initiation: 446 - 550 g
- Housing: individually, in screen-bottom stainless steel cages
- Diet: ad libitum, certified guinea pig chow #5026 (Purina Mills, Inc.)
- Water: ad libitum
- Acclimation period: at least 7 days
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 50 ± 20
- Photoperiod (hrs dark / hrs light): 12/12
- IN-LIFE DATES: From: 1990-06-06 To: 1990-07-16

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

deionized

Concentration / amount:

0.4 mL, 1.0 % w/v

Day(s)/duration:

day 0, day 7, and day 14; 6 h

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

No.:

#1

Route:

epicutaneous, open

Vehicle:

water

Remarks:

deionized

Concentration / amount:

0.4 mL, 0.1 % w/v

Day(s)/duration:

2 weeks after last induction; 6 h

No. of animals per dose:

Test group: 10
Naive control group: 10
positive control group: 4

Details on study design:

RANGE FINDING TESTS:
yes, two range finding groups, 4 animals each.
1st group: undiluted, 75 % w/v, 50 % w/v, 25 % w/v
Due to the level of irritation, a second range finding study ws conducted
2nd group: 10 % w/v, 5 % w/v, 1 % w/v, 0.1 % w/v

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: 6 h
- Test groups: 1
- Control group: 2, naive and positive control
- Site: back of the animals
- Frequency of applications: once a week
- Duration: 3 week
- Concentrations: 1.0 % w/v

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: two weeks after the last inducton exposure
- Exposure period: 6 h
- Test groups: 1
- Control group: 2, naive and positive control
- Site: back of the animals
- Concentrations: 0.1 % w/v
- Evaluation (hr after challenge): 24, 48

Positive control substance(s):

yes

Remarks:

0.3 % w/v 2,4-dinitrochlorobenzene (DNCB) in 80 % ethanol/deionized water

Positive control results:

The mean score of DNCB (all animals) 24 h after challenge was 2.0 (max. score 3.0).

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1 % w/v

No. with + reactions:

0

Total no. in group:

10

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.1 % w/v

No. with + reactions:

0

Total no. in group:

10

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

0.1 % w/v

No. with + reactions:

4

Total no. in group:

4

Clinical observations:

subcutanous hemorrhaging, possible necrotic areas

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

0.1 % w/v

No. with + reactions:

4

Total no. in group:

4

Clinical observations:

subcutanous hemorrhaging, possible necrotic areas

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0.1 w/v

No. with + reactions:

0

Total no. in group:

10

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0.1 % w/v

No. with + reactions:

0

Total no. in group:

10

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance showed no skin sensitizing potential.

Executive summary:

In a primary sensitisation study similar to OECD guideline 406, a group of young adult Dunkin-Hartley guinea pigs (10♂, 446 - 550 g) were epicoutanously treated with the test substance (3x 0.4 mL, 1.0 % w/v in deionized water, once a week for 6 h) at the back (Hazleton Laboratories, 1990). After an incubation period of 2 weeks, the animals were challenged with 0.4 mL of a 0.1 % w/v water solution for 6 h at the back. Readings were done 24 and 48 h after the challenge injection. The sensitizing score was determined according to Buehler et al. (1980). The test substance caused no sensitisation response. A positive control group of 4 animals was treated with 2,4-dinitrochlorobenzene (0.3 % w/v in 80 % ethanol/dionized water). All animals of the positive control group showed signs of sensitisation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

In a primary sensitisation study similar to OECD guideline 406, a group of young adult Dunkin-Hartley guinea pigs (10♂, 446 - 550 g) were epicoutanously treated with the test substance (3x 0.4 mL, 1.0 % w/v in deionized water, once a week for 6 h) at the back (Hazleton Laboratories, 1990). After an incubation period of 2 weeks, the animals were challenged with 0.4 mL of a 0.1 % w/v water solution for 6 h at the back. Readings were done 24 and 48 h after the challenge injection. The sensitizing score was determined according to Buehler et al. (1980). The test substance caused no sensitization response. A positive control group of 4 animals was treated with 2,4-dinitrochlorobenzene (0.3 % w/v in 80 % ethanol/deionized water). All animals of the positive control group showed signs of sensitisation.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008.

The substance is considered not to be classified for sensitisation under Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EU) No 2017/776.