Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

This endpoint is covered by four studies. The key study, an activated sludge respiration inhibition test, shows that the NOEC, EC10 and EC50 after 3 hours were clearly higher than 832 mg TFA/L. The other studies on the mode of action support this result suggesting that TFA presented no acute or chronic effect on acetate metabolism and methanogenic systems.

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:
832 mg/L

Additional information

This endpoint is covered by four studies. A key study, performed according to standard guidelines and GLP, which evaluated the influence of Sodium trifluoroacetate on the activated sludge respiration rate under defined conditions and three supporting studies, not performed according to international guidelines and without GLP statement, which evaluated the effects of trifluoroacetic acid on freshwater microbial communities, on microbial methanogenesis, and on acetate metabolism by stream microbial communities.

In the key 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.

Moreover, three supporting studies indicated no acute/chronic effects of TFA on acetate metabolism (TFA did not reduce methane formation from acetate) and no effect of TFA on tested methanogenic systems (TFA is inert in these methanogenic systems and there is no evident toxicity to either the methanogenic or fermentative population). However, a potential to be actively incorporated by microorganisms have been found.