CNN The Situation Room August 9, 2013 21:50:00
We spent time with the marijuana potency project, where they analyze the marijuana confiscated in various places. back in the 60s and even above 10%. 10 to 13% thc now. they found marijuana with thc concentrations as high as 37%. there has been this breeding of the plant to try and increase the thc. so i think that's true. whether or not it's more addictive is a bit of a tougher question to answer. certainly if you talk to the institute of drug abuse. which we did. they believe a higher potency will be more addictive. this has been a difficult thing to prove. theoretically it doesn't seem so, ...
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