Electric fields do the work there. A charged particle in a magnetic field feels a force (Lorenz force) that act perpendicularly to its velocity. But work is only work if the force is applied in the direction of its velocity. Essentially it's changing its direction of momentum, but not its magnitude.

On the other hand, some magnetic fields (not all) can be transformed into electric fields by a change of reference frame. In that case, the electric field can be used to do work. But I don't believe that's possible on these scales.