Trifluoromethanesulphonic acid

Endpoint summary

Description of key information

Skin irritation study: based on the pH-acid/alkali reserve method and the results of the in vivo study (Longobardi, 2003), triflic acid is considered as corrosive.
Eye irritation: based on the corrosivity of trifluoromethanesulphonic acid, a waiving was proposed.
Respiratory irritation: no specific study is available, however it can be presumed from the corrosive effects on skin that trifluoromethanesulphonic acid may cause respiratory irritation.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 2000-02-28 to 2003-08-19

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Non-GLP study performed similarly to OECD guideline No. 404 (screening test) with some restrictions: no detail on the animal and environmental conditions.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

screening test: no detail on the animal and environmental conditions

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Italia S.p.A.
- Age at study initiation: no data
- Weight at study initiation: 2.7 kg
- Fasting period before study: no
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

IN-LIFE DATES: no data

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): not applicable, the test item is applied undiluted

VEHICLE
not applicable, the test item is applied undiluted

Duration of treatment / exposure:

3 min, 1 hour or 4 hours. Three sites in the same animal were treated with the test item.

Observation period:

1, 24, 48 and 72 hours and 7 days after the end of exposure.

Number of animals:

one animal

Details on study design:

TEST SITE
- Area of exposure: dorsal surface of the trunk
- % coverage: 6.25 cm² (2.5 x 2.5 cm)
- Type of wrap if used: the test item was spread over a gauze square but no data on the dressing.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no data but probably yes.
- Time after start of exposure: no data but probably 3 min, 1 hour and 4 hours after the application of the test item.

SCORING SYSTEM: no data

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

Mean individual score after 3 min exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

0

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

Mean individual score after 3 min exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

1

Reversibility:

not reversible

Remarks:

within 7 days

Remarks on result:

other: necrosis on day 7

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

Mean individual score after 1 hour exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

Mean individual score after 1 hour exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

1

Reversibility:

not fully reversible within: 7 days

Remarks on result:

other: start of necrosis at 72 hrs

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

Mean individual score after 4 hours exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

1.3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

Mean individual score after 4 hours exposure

Time point:

other: Overall 24, 48 and 72 h

Score:

1.3

Reversibility:

not fully reversible within: 7 days

Remarks on result:

other: start of necrosis at 72 hrs

Irritant / corrosive response data:

Brown coloration, hardening were observed within 1 hour (after 1 or 4 hours exposure) or 24 hours (after 3 min exposure) after the end of the exposure period. Erythema around the site of application was observed 24 hours after the end of exposure in the cases of 1 and 4 hours exposure.
Necrosis was observed 7 days after the exposure period and for all exposure time (3 min, 1 hr or 4 hrs). See details in Table 7.3.1/1.

Table 7.3.1/1: Irritant/corrosive response data at each observation time up to removal of animal from the test (3 min, 1 or 4 hrs exposure)

	3 min exposure		1 hour exposure		4 hours exposure
Score at time point / Reversibility	Erythema	Edema	Erythema	Edema	Erythema	Edema
	Max. score: no data	Max. score: no data	Max. score: no data	Max. score: no data	Max. score: no data	Max. score: no data
60 min	0	0	-	0	-	2
24 h	0	1	1	1	2	2
48 h	0	1	1	1	1	1
72 h	0	1	1	1	1	1
Average 24h, 48h, 72h	0.0	1.0	1.0	1.0	1.3	1.3
Reversibility*)	-	n	?	n	?	n

 *) Reversibility: c. = completely reversible;n.c.= not completely reversible; n. = not reversible; ?: no data

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Conclusions:

Under the test conditions, the test item trifluoromethanesulfonic acid (triflic acid) is classified as Skin Corr./Irr. 1B (H314; causes severe skin burns and eye damage) when applied topically to rabbits according to the criteria of the Regulation (EC) 1272/2008 (CLP) and as skin corrosive (C, R34; Causes burns) according to the criteria of the annex VI of the Directive 67/548/EEC.

Executive summary:

In a non-GLP dermal irritation study (Longobardi, 2003) performed similarly to the OECD No. 404 (screening test), one New Zeland White rabbit was dermally exposed to 0.5 mL of undiluted trifluoromethanesulfonic acid (triflic acid) to the dorsal surface of the trunk (skin was shaved before application). Three test sites were covered with a semi-occlusive dressing and tested in the same animal corresponding to 3 different time of exposure: 3 min, 1hr or 4hrs. After the removal of the gauze patch, animals were then observed for 7 days. Skin irritation was assessed and scored at 1, 24, 48, 72 hrs and 7 days after the end of the exposure.  

The mean individual scores calculated within 3 scoring times (24, 48 and 72 hrs) were 0.0 for erythema and 1.0 for edema after a 3 min exposure period, 1.0 for erythema and 1.0 for edema after a 1 hr exposure period and 1.3 for erythema and 1.3 for edema after a 4 hr exposure period. Indeed brown coloration, hardening were observed within 1 hour (after 1 or 4 hours exposure) or 24 hours (after 3 min exposure) after the end of the exposure period. Erythema around the site of application was observed 24 hours after the end of exposure in the cases of 1 and 4 hours exposure. Necrosis was observed 7 days after the exposure period and for all exposure time (3 min, 1 hr or 4 hrs) and started to occur within 72 hrs observation after a 1 or 4 hr exposure period.

In conclusion, under the test conditions, the test item trifluoromethanesulfonic acid (triflic acid) is classified as Skin Corr./Irr. 1B (H314; causes severe skin burns and eye damage) when applied topically to rabbits according to the criteria of the Regulation (EC) 1272/2008 (CLP) and as skin corrosive (C, R34; Causes burns) according to the criteria of the annex VI of the Directive 67/548/EEC.

Reference 2

Endpoint:

skin corrosion: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is a strong acid (pH ≤ 2.0) or base (pH ≥ 11.5) and the available information indicates that it should be classified as skin corrosion (Category 1, 1A, 1B or 1C)

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is classified as skin corrosion, leading to classification as serious eye damage (Category 1)

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Additional information

Skin irritation:

- The pH of a trifluoromethanesulphonic acid aqueous solution at 10% (w/w) is 0.11 and the measure of the acid reserve is 27,0 (as g NaOH/100g substance), (see section 4.20). Based on these data, trifluoromethanesulphonic acid is classified as corrosive into category 1B (H314; causes severe skin burns and eye damage) according to the criteria of the Regulation (EC) 1272/2008 (CLP) and as skin corrosive (C;R34, Causes burns) according to the criteria of the annex VI of the Directive 67/548/EEC.

- One non-GLP dermal irritation study (Longobardi, 2003) performed similarly to the OECD No. 404 (screening test) was available and considered as Weight of Evidence. In this study, one New Zealand White rabbit was dermally exposed to 0.5 mL of undiluted trifluoromethanesulphonic acid to the dorsal surface of the trunk.Three test sites were covered with a semi-occlusive dressing and tested in the same animal corresponding to 3 different time of exposure: 3 min, 1hr or 4hrs. After the removal of the gauze patch, animals were then observed for 7days. Skin irritation was assessed and scored at 1, 24, 48, 72 hrs and 7 days after the end of the exposure.  

The mean individual scores calculated within 3 scoring times (24, 48 and 72 hrs) were 0.0 for erythema and 1.0 for edema after a 3 min exposure period, 1.0 for erythema and 1.0 for edema after a 1 hr exposure period and 1.3 for erythema and 1.3 for edema after a 4 hr exposure period. Indeed brown coloration, hardening were observed within 1 hour (after 1 or 4 hours exposure) or 24 hours (after 3 min exposure) after the end of the exposure period. Erythema around the site of application was observed 24 hours after the end of exposure in the cases of 1 and 4 hours exposure. Necrosis was observed 7 days after the exposure period and for all exposure time (3 min, 1 hr or 4 hrs) and started to occur within 72 hrs observation after a 1 or 4 hr exposure period. under the test conditions, the test item trifluoromethanesulphonic acid is classified as corrosive to skin into category 1B (H314; causes severe skin burns and eye damage) when applied topically to rabbits according to the criteria of the Regulation (EC) 1272/2008 (CLP) and as skin corrosive (C; R34 Causes burns) according to the criteria of the annex VI of the Directive 67/548/EEC.

Eye irritation:

Trifluoromethanesulfonic acid is considered as corrosive (Cat 1B, H314). Therefore, according to the column 2 of the Annex VIII of the Regulation (EC) NO. 1907/2006 (REACh) (section 8.2.1), an in vivo eye irritation study does not need to be conducted if the substance is classified as corrosive to the skin.

Respiratory irritation:

No specific study is available, however it can be presumed from the corrosive effects on skin, pH and acid reserve measurement and the volatility (vapour pressure: 2.4 hPa at 20°C and 3.2 hPa at 25° C) that trifluoromethanesulphonic acid should cause respiratory irritation.

Justification for classification or non-classification

Skin irritation:

Based on the above data, trifluoromethanesulphonic acid is classified as skin corrosive into category 1B (H314; causes severe skin burns and eye damage)according to the criteria of the Regulation (EC) 1272/2008 (CLP) and as skin corrosive (C; R34 Causes burns) according to the criteria of the annex VI of the Directive 67/548/EEC.

Eye irritation:

No data is available. However, as the substance is classified as corrosive, no further test has to be conducted. As mentioned in the Guidance on the application of Regulation (EC) No 1272/2008, a skin corrosive substance is considered to also cause serious eye damage. Therefore, trifluoromethanesulphonic acid is classified as Eye Damage category 1 (H318: Causes serious eye damage).

Respiratory irritation:

No specific study is available, however it can be presumed from the corrosive effects on skin, pH and acid reserve measurement and the volatility (vapour pressure: 2.4 hPa at 20°C and 3.2 hPa at 25° C) that trifluoromethanesulphonic acid should cause respiratory irritation and is classified as STOT SE Cat.3, H335 according to the Regulation (EC) No 1272/2008 criteria and as Xi; R37 according to the Directive 67/548/EEC criteria.