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Environmental fate & pathways

Biodegradation in water: screening tests

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Description of key information

Experimental data show that in common with many highly fluorinated alkanes 1,1,1,2 -tetrafluoroethane (HFC-134a) to be poorly degraded in water. However, as it is gas (boiling point -26°C) of low solubility it is difficult to dissolve in water and will readlily partition to air.

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Additional information

In the closed bottle assay with activated sludge, there was negligible (2 to 3%) biodegradation of HFC-134a after 28 days (Tobeta 1989). However, as HFC 134 is a gas (boiling point -26°C) of low solubility it is difficult to dissolve in water and will readily partition to air. Any that may be present in aqueous waste streams discharged directly into rivers or lakes would be expected to have a half-life with respect to volatilization of several days to a few weeks. A calculation with Epi Win software (US-EPA, 2009) suggests half-lives of about 1 hour for rivers and 96 hours for lakes. Therefore HFC 134a is not expected to be persistent in the aquatic environment.