Distinguish between an antiseptic and a disinfectant with an example of each.

• A. An antiseptic is used on living tissue (e.g., chlorhexidine); Disinfectant is used on inanimate surfaces (e.g., bleach).
• B. An antiseptic is always toxic; Disinfectant is non-toxic.
• C. An antiseptic kills spores; disinfectant cannot kill organisms.
• D. An antiseptic is used on metals; disinfectant on skin.

Answer: (A)

The main idea is when and where the chemical is used and how safe it is for living tissue. An antiseptic is meant to be applied to living tissue to reduce or prevent infection by killing or inhibiting microbes, and it’s formulated to be safe for skin or mucous membranes. Chlorhexidine is a classic example used on the skin or mucous membranes, such as for hand hygiene or prepping a patient.

A disinfectant, on the other hand, is used on inanimate objects and surfaces to destroy most pathogens. Because it’s not intended for living tissue, it’s typically harsher and can be irritating or harmful if applied to skin. Bleach is a common disinfectant used on countertops, floors, and equipment to decontaminate environments.

Why the other statements don’t fit: antiseptics aren’t always toxic to be effective, and disinfectants aren’t universally non-toxic—they’re chosen for safety on surfaces but can irritate living tissue. Also, while some agents can affect spores, antiseptics aren’t defined by spore-killing capability, and disinfectants aren’t restricted to non-living targets. Finally, antiseptics aren’t used on metals specifically, and disinfectants aren’t limited to skin use.