I mean, how do you even answer a question like this? What, 3-4 million people in the city proper, plus millions more in the surrounding suburbs, then the collar counties....
how could you even study a question about consumption of illegal substances? By the quantity of confiscated material?
The logical answer has to be weed, cause it crosses so many age and socio-economic boundaries. It really couldn't be anything else...but your question makes it sound like you are asking our personal favorites, plus you are posting in the Chicago Heroin thread, so it's mostly Midwest junkies here. I haven't smoked weed in longer than I've had an alcoholic drink, years, like over 10 for the weed, maybe 5 since my last drink. But I've got 10 days clean off smack. But I took bupe and clonazepam this morning. So what does that mean in terms of your posted question?
Man, I've got too much time on my hands right now. Gotta start painting the kitchen again. But I have absolutely no interest.