Should I indicate that beryllium compounds exist in a device?
In the EU beryllium was deliberately not included in the RoHS, however, there is/are suggestions which in words from a report says it best;


  Beryllium metal and beryllium oxide is not proposed to be restricted by inclusion in RoHS, however, the presence of beryllium containing parts in EEE above a certain concentration level should be labelled in order to ensure that these parts are dismantled and recycled adequately (cf. Section 6.2.2).


This is from "Study on Hazardous Substances in Electrical and Electronic Equipment, Not Regulated by the RoHS Directive" which was part of a contract from the EU. Available here.

EEE = Electrical and Electronic Equipment.