reaction mass of 2,2,3,3,5,5,6,6-octafluoro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)morpholine and 2,2,3,3,5,5,6,6-octafluoro-4-(heptafluoropropyl)morpholine

PBT assessment

PBT assessment: overall result

PBT status:

the substance is PBT / vPvB

Justification:

All impurities identified as present in FC-770 at > or = 0.1% are either inorganic and thus not subject to PBT evaluation, or are isomers and homologues of FC-770 with physical/chemical properties essentially the same as FC-770 and therefore having PBT characteristics equivalent to FC-770. The ultimate degradation products are hydrofluoric acid (HF, CAS# 7664-39-3), carbon dioxide and oxides of nitrogen which are all inorganic substances and thus do not require a PBT evaluation.

By screening and definitive REACH PBT criteria, FC-770 is very persistent, vP. However, it is only vP in the atmospheric compartment. An evaluation of its fate in water or soil concludes that FC-770 is rapidly removed by volatilization, and it will not partition into water or soil from the atmosphere due to the unfavorable thermodynamics of distribution between the gas phase the aqueous phase. Therefore this substance is non-persistent in the aquatic and terrestrial environments. It is very persistent only in the atmosphere and is subject to long-range transport. Due to mixing in the atmosphere and lack of partitioning out of the atmosphere, concentrations in the biosphere will be negligible. Widespread exposure to FC-770 will not occur.

Based on the provisional BCF result, FC-770 has a very bioaccumulative (“vB”) assignment. It should be noted the study was reliable with restrictions and that availability of a more reliable result showing a suitably low BCF would reverse this conclusion.

Based on available data, FC-770 is not classified as carcinogenic, mutagenic, or toxic to reproduction or specific target organ toxic after repeated dose. FC-770 does not meet the REACH “T” criteria for mammalian toxicity. This information combined with the lack of acute aquatic toxicity can be used to conclude that FC-770 does not fulfill the screening criteria for toxic (“T”).

The data on properties of the substance can be interpreted as meeting the criteria in Annex XIII Section 1 as a vPvB but not PBT substance.

Likely routes of exposure:

Uses in open systems have been removed in this registration update. Uses are limited to closed applications. Given the recent availability of the provisional BCF result used to make the vPvB conclusion, information gathering on routes of exposure, development of exposure scenario, etc., are still being gathered and will be provided in an additional dossier update without undue delay.