Final answer:
The statement is false(b). Heavy metals like mercury and copper are historically used as germicides due to their capability to denature proteins within microbial cells, but tinctures and ointments are not types of heavy metal germicides.
Step-by-step explanation:
The statement that tinctures and ointments are two types of heavy metal germicides is false(b). Heavy metals, such as mercury and copper, have been used historically as germicides and disinfectants because of their ability to denature proteins in microbial cells. This is done by heavy metal ions binding to sulfur-containing amino acids within proteins, thus inhibiting their function and leading to the death of the microbe. Mercury, for example, has a broad spectrum of activity and binds to these sulfur-containing amino acids strongly, leading to bioaccumulation within cells.