2,2,2-trifluoroethyl methacrylate

Endpoint summary

Description of key information

Guinea pig maximisation test: sensitising; similar to OECD guideline 406; GLP; induction: 5% in arachis oil (intradermal) / 100% (epicutaneous); challenge: 100%

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:

1985-05-02 to 1985-06-01

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:

adopted 12 May 1981

Deviations:

yes

Remarks:

No pretreatment to create local skin irritation was done before epicutaneous induction.

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A valid GPMT conducted comparable to guideline with acceptable restrictions is available, which is reliable with restrictions and adequate for classification and labelling purposes. Potency estimation is not mandatory when existing guideline and GLP conforming data are available, which were conducted before the new annex of the REACH Regulation entered into force.

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 8 – 12 weeks
- Weight at study initiation: 420 – 495 g
- Housing: in groups of 4 in solid floor polypropylene cages, furnished with softwood shavings
- Diet (e.g. ad libitum): standard laboratory guinea pig diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3°C
- Humidity (%): 45-65%
- Air changes (per hr): approx. 10/h
- Photoperiod (hrs dark / hrs light): 12/12

Route:

intradermal and epicutaneous

Vehicle:

arachis oil

Concentration / amount:

intradermal induction: 5% in Arachis oil
topical induction: 100% as supplied
challenge: 100% as supplied

Route:

epicutaneous, occlusive

Vehicle:

arachis oil

Concentration / amount:

intradermal induction: 5% in Arachis oil
topical induction: 100% as supplied
challenge: 100% as supplied

No. of animals per dose:

20 (test group, control group)

Details on study design:

RANGE FINDING TESTS:
- intradermal injection of 0.1 mL of 1% and 5% test substance in arachis oil (one guinea pig/concentration)
- observation after 24, 48, 72 h and 7 days for signs of toxicity and necrosis

- topical application of 50% (vehicle: abs. ethanol) and 100% for 24 h (4 guinea pigs, each treated with 50% and 100%)
- observation after patch removal: 1, 24, 48 h for signs of irritation

MAIN STUDY
A. INDUCTION EXPOSURE
Intradermal induction
- No. of exposures: 1
- Test groups: test substance
- Control group: vehicle (arachis oil)
- Site: shoulder region, pairwise injections
- Concentrations:
0.1 mL Freund’s complete adjuvant (FCA)
0.1 mL 5% test substance in Arachis oil (or vehicle only in control)
0.1 mL 50:50 mixture of 5% test substance (or vehicle only in control) and FCA

Topical induction
- No. of exposures: 1
- Exposure period: 48 h
- Test groups: 100% test substance
- Control group: vehicle
- Site: shoulder region, same as for intradermal injections
- Frequency of applications: 1
- Duration:
- Concentrations: 100% (or vehicle in control)
- No pretreatment to create local skin irritation was done before epicutaneous induction.


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: day 21
- Exposure period: 24 h
- Test groups: 100% test substance (right), vehicle (left)
- Control group: 100% test substance (right), vehicle (left)
- Site: flanks
- Concentrations: 100%
- Evaluation (hr after challenge): 24 h, 48 h

Positive control substance(s):

not specified

Remarks:

sensitivity of the animals is regularly checked in the laboratory

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100%

No. with + reactions:

17

Total no. in group:

20

Clinical observations:

reduced body weight gain

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 100%. No with. + reactions: 17.0. Total no. in groups: 20.0. Clinical observations: reduced body weight gain.

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100%

No. with + reactions:

16

Total no. in group:

20

Clinical observations:

reduced body weight gain

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 100%. No with. + reactions: 16.0. Total no. in groups: 20.0. Clinical observations: reduced body weight gain.

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

100%

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No positive reaction.

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 100%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

100%

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No positive reaction.

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 100%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Dose range finding test:

Intradermal application:

- 1 % and 5 %: no evidence of necrosis or systemic toxicity -> 5% is used for the main study

Topical application:

- 100 % (undiluted) and 50%: no irritant response in any animal at any observation -> 100% is used for the main study

 

Main study:

Induction: no documentation of reactions

Challenge:

- no dermal reactions in the control group

- at the 24 h reading 10/20 animals showed moderate diffuse redness (grade 2), 7/20 animals showed scattered mild redness (grade 1) and 3/20 showed no dermal reaction

- at the 48 h reading 7/20 animals showed moderate diffuse redness (grade 2), 9/20 animals showed scattered mild redness (grade 1) and 4/20 animals showed no dermal reaction

Body weight gains of the test group was slightly reduced between day 0 and 24 compared to the control animals. 3 animals in the experimental group showed body weight losses.

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

TFMEA was sensitising in this GPMT test.

Executive summary:

In a dermal sensitisation study similar to OECD guideline 406, adopted 12 May 1981, with TFMEA (not given in the study report, but according to sponsor >90%), 20 young adult female Dunkin-Hartley guinea pigs were tested using the method of Magnusson & Kligman (Guinea Pig Maximisation Test).

Test concentrations were selected based on pretest results. For the intradermal and epicutaneous induction procedure concentrations of 5% in arachis oil and 100% were used, respectively. The test article concentration for the challange procedure was 100%. No pretreatment to create local skin irritation was done before epicutaneous induction.

After challenge10/20 animals showed moderate diffuse redness (grade 2), 7/20 animals showed scattered mild redness (grade 1) and 3/20 showed no dermal reaction at the 24 h observation. Similar results were observed after 48 h. No dermal reactions were noted in the control group.

 

The test material produced a response in 85% of the animals. According to CLP, EU GHS (Regulation (EC) No 1272/2008), a response of at least 30% of the test animals of an adjuvant type guinea pig test method for skin sensitisation is considered as positive.

TFMEA is a dermal sensitiser in this study.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Two relevant, reliable (Klimisch score 2; reliable with restrictions) studies are available for assessment of the sensitising potential of TFMEA:

In a dermal sensitisation study similar to OECD guideline 406, adopted 12 May 1981, with TFMEA (not given in the study report, but according to sponsor >90%), 20 young adult female Dunkin-Hartley guinea pigs were tested using the method of Magnusson & Kligman (Guinea Pig Maximisation Test).

Test concentrations were selected based on pretest results. For the intradermal and epicutaneous induction procedure concentrations of 5% in arachis oil and 100% were used, respectively. The test article concentration for the challange procedure was 100%. No pretreatment to create local skin irritation was done before epicutaneous induction.

After challenge10/20 animals showed moderate diffuse redness (grade 2), 7/20 animals showed scattered mild redness (grade 1) and 3/20 showed no dermal reaction at the 24 h observation. Similar results were observed after 48 h. No dermal reactions were noted in the control group.  

The test material produced a response in 85% of the animals. According to CLP, EU GHS (Regulation (EC) No 1272/2008), a response of at least 30% of the test animals of an adjuvant type guinea pig test method for skin sensitisation is considered as positive. TFMEA is a dermal sensitiser in this study.

This finding is supported by an in vitro test for sensitisation:

In an in vitro dendritic cell activation test theskin sensitisation potential of TFMEA was assessed.The test is performed using the human pro-monocytic cell line U937 as surrogate for dendritic cells. As readout, the change in the expression of the cell membrane marker CD86 measured by flow cytometry after 48 h of exposure is determined. A test substance is predicted to activate dendritic cells when CD86 cell surface expression exceeds the threshold of 1.2 in relation to vehicle control in at least two independent experiments.

After 48 hours of exposure to TFMEA CD86 expression was induced in U937 cells at concentration affording at least 70% viability. From this it is concluded that the test substance does induce dendritic cell activation and therefore can be considered as potential sensitiser.

There is no information available for respiratory sensitisation. Therefore, there is a data gap in this respect. However, the data gap cannot be fulfilled with experimental data, since there is no internationally accepted animal model for respiratory sensitisation. In case human data for respiratory sensitisation emerges, this will be taken into account.

No human information is available for skin sensitisation. However, there is no reason to believe that these results would not be applicable to humans.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

Inhalation is no relevant route of exposure.

Justification for classification or non-classification

According to regulation (EC) 1272/2008, TFMEA is classified as skin sensitiser (Category 1) and labelled with H317.    

According to the former European directive on classification and labelling 67/548/EEC, TFMEA is classified as Xi (irritant), R43 (May cause sensitisation by skin contact).