This depends on your city's laws by the way. Where I live, as long as it is in a puncture-proof container and labeled properly it can be disposed of in the trash. I purchase the $5 dollar sharps containers from Walmart and toss em in the dumpster after I seal the lid. Just an FYI.
Edit: I figured I'd paste what my city has to say for guidelines:
- Place all needles and syringes in a secured puncture proof plastic container with a screw-on lid (for example: a rigid detergent, bleach or fabric softener bottle).
- Clearly label the container ***8220;NON-RECYCLABLE***8221; and dispose of it in your trash container.
- Once filled to no more than 2 inches from the top, tightly secure the lid and reinforce with duct tape.
- Place the container into your trash; do not place this container in with your other recyclables.