Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Substance is a gas of low solubility and is expected to quickly disappear from the aquatic phase. Therefore, any impact on the aquatic environment is expected to be low. According to 9.1.3 Column 2 of REACH Annex VIII aquatic toxicity studies need not be conducted if there are mitigating factors indicating that aquatic toxicity it unlikely to occur.

Given that tetrafluoroethylene is a gas and the consequent difficulty to test it meaningfully in aquatic media, no experimental aquatic toxicity data are available. Instead, QSAR methods have been used to estimate the acute toxicity of the substance to the aquatic organisms.

The toxicity of TFE to fish, daphnia and algae were estimated using the US EPA program ECOSAR v1.00 (2009).

Predicted acute toxicity to aquatic organisms

 Organisms  Duration (h)  Effect/Parameter Predicted Concentration (mg/l)
 Fish  96  Lethality LC50  379
 Daphnia  48  Immobility EC50  190
 Algae  96  Growth inhibition  64

The predicted toxic concentrations for fish and daphnia are considerably greater than the solubility limit of TFE in water of 110 mg/l, which was only achievable in equilibrium with a gas phase containing 1 atmosphere of TFE. The predicted Algae EC50 is below the solubility limit; however, experience with other fluorocarbons shows that for this endpoint ECOSAR v1.00 predictions tend to be signifcantly lower than experimental values, and so the predicted algae EC50 of 64 mg/l for TFE may well be conservative. Given that there is no direct or indirect exposure of the aquatic environment to TFE, and that it will disappear rapidly from water, likely concentrations would be orders of magnitude below the solubility limit. Therefore, it is concluded that TFE will not be toxic in the aquatic environment.