With 60 tonnes of khat imported to the UK each week, a chemist at the University of Birmingham makes the case for better scientific literacy of the now banned herbal stimulant.

Dr Simon Cotton

“The home secretary, Theresa May's decision to reject the advice of her scientific advisers and ban Khat has caused something of a controversy. Her main justification was the fear that Britain could become a regional trafficking hub for the substance, which is outlawed in the majority of other northern European countries."

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You can listen to Dr Simon Cotton's podcast about the subject of Khat on our Soundcloud channel. Full transcript available on the Chemistry World website.