However, breathing its dust, as formed when machining or welding may cause serious lung damage. [1]Beryllium compounds are known human carcinogens when inhaled. [2] As a result, beryllium copper is sometimes replaced by safer copper alloys such as Cu-Ni-Sn bronze.[3][edit]UsesBeryllium copper is used in springs and other parts that must retain their shapes during periods in which they are subjecte