In your original comment, you’d said “toxic”. toomuchtodo was right to note exactly what your source explains: they’re mostly recyclable (though many places aren’t ready for the blades because they’re so big!) and if not they can be scrapped and left in a landfill. Toxic means something specific, and isn’t just “can’t be recycled”.
Do you have any information on that, I'd never heard of that being the case?