Is erosion of enamal at root from the teeth whitening trays/strips possible?

Teeth Erosion: I have not seen any enamel distruction after using dental strips to clean teeth much more root erosion because it is deep inside the gum not reach by cleaning.

Not enough evidence: If you happen to be experiencing sensitivity at the gumline after using your trays/strips, it is possible that the gel is causing that. However, it is not likely that gel is causing any recession. You may also be noticing it more, since the dentin where the enamel stops will not whiten as enamel does and you will see the difference at the gumline more so with the enamel becoming lighter.

Yes.: Depending on the material used to whiten, you can affect the enamel. If the whitening gel/strips are not ph balanced and are acidic, it will remove calcium from the enamel making it soft and easily brushed away. Dental offices typically should be offering a gel to use in the trays that is safe.