In my parnoid time....
I used to use a wire cutter to break the needles into small pieces and put the whole deal into a aluminum-foil lined measuring cup. Put in the oven for 450 for a while, it melts into a big lump of goo.
Let cool, pull out and finish wrapping with foil. Dump in trash. Nobody gets the needle or risk of infection. Hard to tell what it was or what was in it.