Insert File Data into Container via Applescript

[splatto]

The following Applescript step will insert a reference to a file into a container field >

set cell "MessageData" of new_rec to file aPath

where aPath is defined as >

set aPath to "file:../../../" & POSIX path of aFile

Is it possible to script FileMaker to insert 'the data' of a file into a container field rather than just a reference.