I believe the *other* reason for the different formulas for medical CA's is the cure rate... the stuff we use generates significant heat during the polymerization process. Here's another quote from the link to the woodturning site: "Medical grade cyanoacrylates by contrast, are typically n-butyl-ester, isobutyl ester, or octyl ester based and are specially prepared to cure with as little heat during polymerisation as possible. Excessive heat or rapid cure during polymerisation can lead to tissue necrosis."

Regards

Kaptain "I dislike necrosis, particularly when my internal organs are involved" Zero