Ethyl trifluoroacetate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

1 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.1 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.1 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

83.2 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

4.6 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.46 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

8.3 µg/kg soil dw

Assessment factor:

100

Extrapolation method:

assessment factor

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

Ethyl trifluoroacetate (TFAE) reacts with water and is degraded in Trifluoroacetic acid (TFA) and ethanol. A read across strategy is used with TFA which is the relevant substance for risk assessment and classification and labelling purposes. However, in aqueous solution, the pH of this substance is naturally low and for testing under realistic environmentally conditions either the sodium salt (NaTFA) or pH adjustment are required.

 

Aquatic toxicity:

Among all the species tested, a toxic effect (growth inhibition) was found only for the algae Selenastrum capricornutum which lead to a R52/53 classification for the environment. The lowest value of the range of EC50 that lead to such a classification is 10 mg/L which is in line with the ErC50 for Selenastrum capricornutum calculated at 8.5 mg/L. In total six other freshwater algae and three marine algae were tested and no toxicity was found at the highest concentrations tested (up to 1997 mg/L TFA). Neither short term nor long term toxicity were found on the invertebrate Daphnia magna giving a EC50 (48h) > 999 mg/L and an NOEC (21d) = 25 mg/L of TFA. Also, a low short term toxicity was found on the freshwater fish Pimephales promelas and an L(E)C50 (96h) of 10 g/L TFAE was derived. Therefore, it is postulated that, with high probability, the most sensitive species has been examined and that the lowest value in the range of toxicity consistent with a R52/53 classification can be use to derive the PNECs for the aquatic compartments.

Moreover, one key study is available to evaluate the influence of NaTFA on the activated sludge respiration rate. In this study, the 3 hours EC10, EC20 and EC50 could not be quantified because up to the highest nominal test concentration (1000 mg NaTFA/L, corresponding to 832 mg TFA/L) less than 10% inhibition was noted. Nevertheless, the 3-hour EC20 and EC50 are clearly higher than 832 mg TFA/L under the present test conditions. The NOEC/EC10 may be established above 832 mg TFA/L.

 

Environmental fate and pathways:

TFAE is rapidly hydrolysed to TFA with a half-life time of 57 minutes. However, TFA is not readily biodegradable.

Conclusion on classification

TFAE is classify as the harmonised classification of Trifluoroacetic acid (TFA).

Classification according to Annex VI of Directive 67/548/EEC: R52/R53 for the environment, based on the toxicology observed on Selenastrum capricornutum.

GHS classification: Aquatic chronic 3/ H412