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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

No acute and chronic ecotoxicity data are available for HFC 125.

Acute aquatic toxicity

In view of the nature of the substance, the performance of aquatic ecotoxicity studies would feasible only in close system and would likely not be indicative of the natural exposure conditions. The assessment of the possible aquatic toxicity of HFC 125 has been carried out by considering available data on structurally analogue substances.

The analogue approach for the HFC category is justified and documented in the position paper "Use of categories approach in environmental hazard assessment of hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs)", attached in the Endpoint Summary in Section 6 of the Technical Dossier (Ecotoxicological Information).

Experimental data for acute toxicity on fish are available for HFC 134a (1,1,1,2 -tetrafluoroethane), HFC 245fa (1,1,1,3,3-pentafluoropropane) and HFC 365mfc (1,1,1,2,2 -pentafluorobutane). In all cases, a low acute toxicity to fish was observed (LC50 = 450 mg/l for HFC 134a; LC50 > 100 mg/l for HFC 245fa and LC50 >200 mg/l for HFC 365mfc).

Similar results were obtained with the same structural analogues in the acute toxicity studies on Daphnia magna (EC50 = 980 mg/l for HFC 134a; EC50 > 100 mg/l for HFC 245fa and EC50> 200 mg/l for HFC 365mfc).

Finally, the toxicity on algae was estimated by considering available experimental data on HFC 245fa and HFC 365mfc and QSAR estimation carried out for HFC 32 (difluoromethane). Also in this case all considered results lead to an expected low toxicity for HFC 125 (EC50 > 118 mg/l for HFC 245fa; EC50 > 114 mg/l for HFC 365mfc and EC50 = 142 mg/l for HFC 32).

Chronic aquatic toxicity: HFC 125 is not emitted into the aquatic compartment during its manufacturing and uses. Besides, a negligible partitioning in the aquatic compartment is expected following the emission of HFC 125 in the environment. For those reasons, no chronic toxicity to aquatic biota is expectable for HFC 125.