Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Acetylene is not expected to hydrolyse based on a lack of hydrolysable functional groups. However, according to Atkinson (1989), the kinetic rate constant for the reaction of acetylene with OH radicals is estimated to be 0.82 E-12 cm3/mol/s, indicating that the atmospheric half-life would be 13.12 days. In addition a half-life of 382 days for ozone radicals has been reported (Atkinson 1989).

Reliable data are not available to demonstrate that acetylene is readily biodegradable, and for the purposes of a risk assessment, ready biodegradability will not be assumed.

Acetylene has the potential to rapidly volatilise from surface waters, based on a calculated Henry's Law constant of 2.20E+003 Pa m³/mol at 25 ºC. It is not expected to partition to suspended matter or sediments based on its log Kow of 0.37.