Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

C4 fluorinated isonitrile is fully fluorinated at all atoms except the nitrile group. It is a gas under normal conditions, with a boiling point of -4.7 °C. It is used as an inert insulating gas for high-voltage electrical components. Potential releases would be during transfer, filling, or emptying steps, or during catastrophic failure of the filled component. Such releases would be to the atmospheric compartment only. In the atmosphere, this substance is subject to reaction with hydroxyl radical with an atmospheric lifetime of 35 years. This substance does not attain high concentrations in water, and is hydrolytically unstable. When a headspace containing this substance is held in contact with water in closed systems, substantial portions dissolve in the water phase and form heptafluoroisobutyramide. However as a gas, limited contact with the aquatic compartment is expected. Hydrolysis in the atmosphere cannot be excluded given the facile reaction with water in closed systems and the relatively long atmospheric lifetime. The effect of hydrolysis in the atmosphere would be to reduce atmospheric lifetime of the isonitrile, with deposition of the amide to the terrestrial and the aquatic compartments. The Global Warming Potential (100-y integrated time horizon) relative to carbon dioxide is 2300.

 

Most degradation is expected to occur in the atmosphere. As the C4 fluorinated isonitrile is not expected to partition to aquatic or terrestrial compartments, biodegradation is not relevant. If present, it is not expected to be subject to biodegradation based on results of a QSAR study.