I'd like to know what your source is for that statement.

Perhaps you should elaborate. That's a pretty simple response. Have you found something that refutes the recent respected studies that show evidence that kava (water extracted root at least) is not toxic to the liver?

Here is the study that I refer to:

http://www.springerlink.com/content/.../fulltext.html

the study does not address alcohol or acetone extraction methods, or the use of non traditional parts of the plant ... which I would be suspicious of.

Its a shame that people might not use a miraculous root like kava based on dis-proven information about liver damage. Large populations use it on the islands without liver damage, mind you, there kava is water extracted. Not much evidence either way, that I can find so far on alcohol / acetone extractions but that is another issue.