It's possible, but not known. From my readings on the net, no one even knows when the plant makes the most salvinorin A. You could find out by smoking them plain and then making an extract and smoking that. If you have little to no effect you would know there is little to no salvinorin A in the flowers. If you do get an effect you could compare it subjectively to a similar concentration extract or perform a more quantative experiment to measure the salvinorin A content.