Reaction mass of chlorodifluoroacetic acid and trifluoroacetic acid

Endpoint summary

Description of key information

The available study on chlorodifluoroacetic acid showed that the substance is corrosive with high score according to the OECD 404 scale.
Additionally, measured pH and acid reserve done on each component showed that chlorodifluoroacetic acid and trifluoroacetic acid are corrosive.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 03 jan 1990 to 19 sept 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study, OECD 404 compliant.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bancel (Albon - 26140 Saint Rambert d'Albon - France)
- Age at study initiation: adult, 3 males
- Weight at study initiation: 2.4 and 2.5 kg
- Housing: Individually in polystyrene cages (560 x 355 x 315 mm)
- Diet (e.g. ad libitum): 150 g pe animal and per day of rabbits food pellets (U.A.R, formula 112 - U.A.R, Villemoison - 91360 Epinay/Orge - France)
- Water (e.g. ad libitum): softened and filtered water (15 µm), ad libitum
- Acclimation period: 13 days before treatment

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3°C
- Humidity (%): 30 to 70%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12h/12h, lighting: 7h30 - 19h30

IN-LIFE DATES: From 03 jan 1990 To 05 jan 1990

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 ml

Duration of treatment / exposure:

4 hours

Observation period:

14 days maximum

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: back and flanks
- % coverage: 6 cm²
- Type of wrap if used: perforated adhesive tape 10 cm width.

SCORING SYSTEM: EU

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks:

Animals were killed at 48 hours for human reason

Remarks on result:

other: Necrosis

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

> 3 - <= 4

Max. score:

4

Reversibility:

not reversible

Remarks:

Animals were killed at 48 hours for human reason

Remarks on result:

other: reaction bigger than application area

Other effects:

Total necrosis of the skin. That's why all animals were killed at 48 hours.

Results:

Observation time	Erythema	Edema
1 hour	4a/4a/4a	4/4/3>
24 hours	4a/4a/4a	3>/4/4
48 hours	4n>/4n>/4n>	n/n/n
72 hours	-/-/-	-/-/-
Mean (24, 48 and 72 h)	4/4/4	-/-/-

a : eschar on application area

> : Reaction bigger than application area

n: total necrosis of the skin

Interpretation of results:

Category 1 (corrosive)

Conclusions:

Chlorodifluoroacetic acid is corrosive category 1 according to CLP 1272/2008/EC. However, the exposition time of 4 hours does not allow to differentiate between A, B or C categories.

Executive summary:

In a GLP study, 0.5 ml of Chlorodifluoroacetic acid was applied on the back or flanks, of 3 New Zealand White rabbits (males), under semiocclusive conditions during 4 hours.

The highest score (4) was observed only after 1 hour of observation.

Regarding the total necrosis observed in all animals, bigger than the application area, animals were killed for human reason after 48 hours.

Based on these observation, Chlorodifluoroacetic acid can be classified as corrosive for the Skin, Category 1 according to CLP 1272/2008/EC. In absence of shorter exposition time it is not possible to apply a stronger classification based on this study alone.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Trifluoroacetic acid has a pH of 0.45 in aqueous solution of 10% (w/w) and an acid reserve of 35 g NaOH for 100g TFA.

Chlorodifluoroacetic acid has a pH of 0.33 in aqueous solution of 10% (w/w) and an acid reserve of 30.8 g NaOH for 100g CDFA.

One skin irritation study on chlorodifluoroacetic acid is available and showed that it is corrosive to the skin. The CDFA skin corrosion study does not allow to classify it as skin corrosive category 1A, 1B or 1C because the exposition time was 4 hours. However, considering the very strong effects observed in the CDFA skin corrosion study, the pH and acid reserve of both CDFA and TFA, the reaction mass of these compounds is classified as skin corrosive category 1A (according to the CLP 1272/2008).

Justification for classification or non-classification

Based on the available study, pH and acid reserve, the reaction mass is considered as corrosive and classified:

- Skin corrosion 1A H314: "Causes severe skin burns and eye damage", according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.