Here is a list of things people have searched for which are not recyclable and are of such low value you should just put them in the trash.

arm and hammer baking soda, fridge filter, desiccant, diatomite, hair brush, hair clips, handphone case, helium balloons, insulation, ipad cover, loofah, mousepad, notebook cover, phone casing, phone holder, plasticine, rafia string, shaver, shaving razors, shoelaces, stress ball, toothbrush, toothpaste tube, tracing paper, velcro, pop socket, screen protector, disposable slippers, eye mask, earbud holder, earphone case, deodorant bottle, aligner trays

This list is not exhaustive. We add to it all the time.

Note that most items which are mixed material (a mixture of plastic, glass, paper or metal) are not recyclable in blue bins. To the extent that you can separate the materials, the chance of recycling improves.

Likewise, things made of rubber or silicon cannot be recycled. Similarly, items made of stone, sand or other minerals (eg diatomite mat) cannot be recycled.