Potassium trifluoroacetate

Endpoint summary

Additional information

Potassium trifluoroacetate (TFAK) is very soluble in water. In the environment, it is ionized into the trifluoroacetate anion and the potassium cation. As potassium is not potentially toxic to aquatic organisms, the toxicity effect of TFAK should be the activity of the trifluoroacetate moiety.

Short-term toxicity data

Reliable acute data for the trifluoroacetate moiety are available for three trophic levels: algae, invertebrates and fish. In aqueous solution, the pH of the substance is naturally low and for testing on organisms either the sodium or potassium salt (TFANa or TFAK) or pH adjustment were required.

• Algae: Among all the algae species tested, an adverse effect on growth inhibition was found only for the algae Pseudokirchneriella subcapitata, resulting for the key study performed with trifluoroacetic acid adjusted to neutral pH, in a 72h-ErC50 of 237 mg TFA/L (Chabot, 2017). Six other freshwater algae, three marine algae and three freshwater aquatic plants were tested and no toxicity was found on none of the species at the highest concentrations tested (up to 2 g/L).


• Aquatic invertebrates: No effect of TFAK was observed to Daphnia magna up at 100 mg/L. Moreover, in a reliable key study available for sodium trifluoroacetate, the EC50 (48h) to Daphnia magna was greater than or equal to the highest concentration tested of 1200 mg/L.


• Fish: Two acute studies (one key and one supportive) are available for sodium trifluoroacetate on Danio rerio. No acute effects were observed at the highest concentration tested of 1200 mg/L Therefore, an LC50 (96h) > 1200 mg/L was derived for fish.

Table: Overview of reliable acute toxicity data for TFA for hazard assessment purposes

Species	Parameter	Endpoint	Value (mg/L)	Test substance	Reference
Pseudokirchneriella subcapitata	Growth rate	72h-ErC50	237	TFA (pH adjustment applied)	Chabot, 2017
Daphnia magna	Mortality/Immobility	48h-EC50	>100	TFAK	Cerbelaud, 2000
Danio rerio	Mortality	96h-LC50	>1200	TFANa	Groeneveld et al, 1992

Chronic toxicity data

Reliable chronic data are available for three trophic levels: algae, invertebrates and fish. In aqueous solution, the pH of the substance is naturally low and for testing on organisms either the sodium or potassium salt (TFANa or TFAK) or pH adjustment were required.

• Algae: In the study of growth inhibition of the algae species Pseudokirchneriella subcapitata performed by Ineris (Chabot, 2017), a 72h-ErC10 of 5.6 mg/L was determined for trifluoroacetic acid (adjusted to neutral pH).


• Aquatic invertebrates: A GLP compliant guideline study with sodium trifluoroacetate is available for the long-term toxicity in aquatic invertebrates (Kuhl, 2010). The 21-day NOEC forDaphnia magna was determined to be ≥ 30 mg TFANa/L for the reproduction rate and for the survival of the adult test animals. While this value is taken as the NOEC for invertebrates it is not a true NOEC as no effect concentration was statistically calculated.


• Fish: A chronic fish study according to OECD 210 (Liu Min, 2019) was performed with the reaction mass of potassium trifluoroacetate (TFAK) and potassium trifluoromethanesulphinate (TFSK) on Gobiocypris rarus. The NOEC was set to ≥10 mg/L for the test substance, corresponding to a re-calculated NOEC (nominal) for TFAK of ≥ 4.7 mg/L.

Table: Overview of reliable chronic toxicity data for TFA for hazard assessment purposes

Species	Parameter	Endpoint	Value (mg/L)	Test substance	Reference
Pseudokirchneriella subcapitata	Growth rate	72h ErC10	5.6	TFA (pH adjustment applied)	Chabot, 2017
Daphnia magna	Reproduction/Survival	21d-NOEC	30	30% aqueous solution of TFANa	Kuhl, 2010
Danio rerio	Mortality	35d-NOEC	3.8	Reaction mass of TFSK/TFAK	Liu Min, 2019