Radio personalities are pulled from the general population. The math tells you that pretty much any drug that can be ingested has been ingested by someone in Seattle radio history, likely in the same proportion as the general population. Adding in the stressors that come with radio, the isolation that can happen with the odd hours, and my anecdotal view that radio can draw some real characters with serious problems, the percentage might actually be higher than general population numbers.
So, to answer your question, yes.
Pat O'Day (for example) pretty much told us he did ALL the drugs back in his glory daze. Fortunately for him he was able to get cleaned up and have a healthy and long life after.