Brian Gaff (Sofa) formulated the question :
One word of warning though, its awfully tempting, I am told to vacuum the
spilled toner inside the printer to clean up printouts. DON'T!. Toner is low
melting point plastic with a conductive additive and very very small
particles. The vacuum used for this needs a special filter to stop it getting
into the and seizing it and shorting it out!

I agree, much better to take it outside on a dry day and if you have an
airline - blow it out, but standing upwind of it to avoid breathing in
the dust.