When dealing with syringes you need to be very careful how you dispose of them, I personally make sure every needle is bent after use, and then i put them in the sharps container. It becomes someone else’s responsibility to take care of it when I sneak my sharps container into the hospital. I drop off all of my needles in their containers because there isn’t an safe/easy way for me to dispose of them. I have no idea what happens next to be completely honest, but I assume it has something to do with melting the needles down and dumping the rest.