Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

In the presence of water, CyreneTM, with its anhydrous keto group [C=O] gains water to form the corresponding hydrated geminal diol or Gem Diol [C(OH)2]. An equilibrium is established rapidly and is completely reversible. When the amount of water is reduced, the Gem Diol loses water regenerating anhydrous CyreneTMin its keto form. The ratio of the two forms depends upon the amount of water present and hence the polarity of the solution. Further information is available in the Physical and chemical properties endpoint summary (IUCLID Section 4).


At concentrations relevant for studies of environmental fate properties, the Gem Diol form predominates and as such the environmental hazard assessment is based on the properties of the Gem Diol.

The submission substance attained 99% biodegradation (DOC removal) in 28 days in a screening test for biodegradation in water (OECD 301A). Since in aqueous media the Gem Diol predominates, the biodegradation observed is also considered to reflect that Gem Diol is readily biodegradable.

Additional information