How is salvinorin A extracted?

Hi, I've recently been pondering about experiencing salvia, but am slightly concerned about the extraction methods used, i found on the Internet that extraction methods include the use of Acetone, isopropyl, Chloroform and Naphtha in making the standardized extractions, (X5, X10 etc)



surely this cant be good to take, and residual from the solvents are bound to be left, the extraction methods i found all said it should not be used for commercial purposes but i cant find any other methods so how do they do it commercially?



Any comments/replies would be brilliant, cause I am not sure i would want to take the standardized versions if this is the case and would much rather take just the dried leafs.



Regards

Marcus