The HP toner cartridges should not be thrown away. They should be recycled. To recycle them, put them in a box and slap a UPS label on it. The UPS label can be found in one of three ways:
1) Look in the manual inside the box. There is one there. 2) If there is no manual inside the box, then look in the office drawer (where the machine room keycard is kept) and take one from there. 3) If there are none there or you can't find them, then call HP at 1-800-752-0900 Ext. 1872 and talk to the nice lady there. She will send you some labels.
After you have slapped the label on, call UPS and ask them to come pick up. Or check with the Campus Activities Complex. They might be able to work it into their UPS stuff.