Final answer:
The three families of agents used in embalming fluids are alkylating agents such as formaldehyde, halogens like iodine, and heavy metals, though the latter are less favored due to toxicity concerns. Alcohols and phenolics are also disinfectants but are not primarily used in embalming fluids.
Step-by-step explanation:
The three families of disinfection/preservative agents used in embalming fluids are alkylating agents, halogens, and heavy metals. Alkylating agents such as formaldehyde are known for their sterilizing capabilities at low temperatures and are broadly used for tissue storage and as embalming fluids. Halogens like iodine work by oxidizing cellular components and can be complexed with organic molecules in formulations such as povidone-iodine. Although some heavy metals like mercury and silver have been used as preservatives, their toxicity and environmental risks have made them less favorable.
Alcohols are another category often used as disinfectants. Ethanol and isopropyl alcohol denature proteins and disrupt cell membranes, making them effective in destroying microbes. However, they are not typically included in the primary list of agents for embalming fluids. Phenolics and other chemical preservatives possess long-acting disinfectant properties and are used in a variety of cleaning and preservation contexts.