I used to work for the California Department of Toxic Substances Control. Audio vacuum tubes were not regulated when I worked there. I called up their Regulatory Assistance Officer to find out if the regulations had changed. I found out the regulations had not changed and had fun reminiscing with another old-timer.
In summary: Audio vacuum tubes are not a federally regulated or California regulated waste. Therefore the chances are very good (but not guaranteed) they are not regulated in any given state. That means household waste collection sites would probably

if you tried to dispose of tubes there and would not know what to do with them. Of course it does not hurt to check with them if you have a lot of tubes to dispose of.
Thanks to all who expressed concern and desired to do the "green thing".
