The agents in this class are bicyclophosphates and bicyclothiophosphates. This class of agents is not speciﬁcally listed in theChemicalWeaponsConvention nor is it covered by the languageof thegeneraldeﬁnitions in theSchedules. Someof these chemicalshavebeenused as ﬁre retardants, oil lubricants, and for medicinal research. They also occur as breakdown products in some synthetic turbine engine lubricants and some rigid polyurethane foams. These materials are fourth generation chemical warfare agents that have been evaluated
by various countries. They are relatively easy to synthesize. No information is available on dispersing these agents. However, because they produce negligible vapor, they will be somewhat difﬁcult to deliver in a manner that will produce immediate casualties. Minimal information about these agents or potential research programs concerning these
agents has been published in the unclassiﬁed literature. There is no information to indicate that these agents were ever stockpiled or have ever been used on the battleﬁeld.