Trifluoroacetic anhydride

Endpoint summary

Description of key information

Acute toxicity: oral: Waiving
Acute toxicity: dermal: Waiving
Acute toxicity: inhalation: NOAEC = 300 mg/m3 (vapors) based on local irritation effect of the nasal cavity epithelium.

Additional information

Acute oral:In accordance with column 2 of REACH Annex VII, the acute oral study (required in section 8.5.1) does not need to be conducted as trifluoroacetic anhydride (TFAH) is classified as corrosive (see §7.3.1).

Acute dermal:In accordance with column 2 of REACH Annex VIII, the acute dermal study (required in section 8.5.3) does not need to be conducted as TFAH is classified as corrosive (see § 7.3.1).

Acute inhalation:

The objective of the study was to provide data on the no-effect level after acute (4-hour) exposure of inhaled trifluoroacetic acid in rats. In dose range finding experiments it was established that male animals were more sensitive than female animals and that exposure to 300 mg/m³resulted in treatment-related effects. Therefore, four groups of 10 male rats were exposed to target concentrations of 0 (control), 30, 100 and 300 mg/m³ trifluoroacetic acid during a single period of four hours. Five animals/group were sacrificed 1 day after exposure and the other 5 animals/group were sacrificed after a 14 day recovery period. The actual concentrations of trifluoroacetic acid in the test atmosphere during exposure were 31.2 (± 1.6) mg/m³, 119.8 (± 2.0) mg/m³and 335.9 (± 8.2) mg/m³for the low, mid and high concentration groups, respectively. Clinical abnormalities, mortality or treatment-related differences in body weight were not found. Five rats/group were sacrificed the day after the exposure. At necropsy, treatmentrelated macroscopic abnormalities were not seen. At the microscopic level, very slight focal degeneration of the respiratory epithelium lining the dorsal part of the septum at the second level of the nasal cavity was seen in 4 out of 5 animals of the high concentration group. Significant differences in biochemical parameters in bronchoalveolar lavage fluid between the exposed groups and the control group were not found. There were no exposure-related differences in total white blood cells counts and differential white blood cell counts in broncho-alveolar lavage fluid.

The other animals, also 5 rats/group, were sacrificed after a recovery period of 14 days. At necropsy, treatment-related macroscopic abnormalities were not seen. At the microscopic level, the focal degeneration in the nasal cavity observed in the animals sacrificed one day after exposure, was no longer seen. No other abnormalities at the microscopic level were seen. Significant differences in biochemical or white blood cell parameters in broncho-alveolar lavage fluid were not found. In conclusions, the only treatment-related effect was a very slight histopathological change at the

second level of the nasal cavity in animals of the high concentration group sacrificed one day after exposure. This lesion was reversible within a 14-day recovery period. Therefore, the mid concentration exposure level (119.8 mg/m³trifluoroacetic acid) was a No Observed Effect Level (NOEC) and the high concentration exposure level (335.9 mg/m³trifluoroacetic acid) was considered a Low Observed Adverse Effect

Level / No Observed Adverse Effect Level (LOAEC/NOAEC).

Justification for classification or non-classification

Harmonised classification:

No harmonised classification is available for Trifluoroacetic anhydride.

Self-classification proposed:

Trifluoroacetic anhydride is classified as:

- Acute Tox. 4 (Harmful if inhaled, H332) according to the Regulation (EC) No 1272/2008 including ATP1,

- Harmful by inhalation (Xn, R20) according to the Directive 67/548/EEC.