Which of the following is a disinfectant?

Which of the following is a disinfectant?

• A. Formaldehyde gas
• B. Alcohols
• C. Peracetic acid
• D. Aldehydes

Answer: (B)

Disinfectants are agents that kill or inactivate many microorganisms on inanimate surfaces, but they don’t reliably destroy all forms of life such as bacterial spores. Alcohols, like ethanol or isopropanol, are widely used as disinfectants because they rapidly denature proteins and disrupt cell membranes, providing quick broad-spectrum activity against many bacteria and enveloped viruses. They’re effective for surface and instrument disinfection and for hand sanitizing when formulated appropriately, though they aren’t sporicidal and won’t sterilize equipment that may harbor spores. The other options are more associated with sterilization or high-level disinfection under controlled conditions: aldehydes (including formaldehyde) and related compounds are used as potent sterilants and fixatives, and peracetic acid is employed as a high-level disinfectant/sterilant in specialized settings. Thus, alcohols best fit the common definition of a disinfectant in routine use.

Disinfectants are agents that kill or inactivate many microorganisms on inanimate surfaces, but they don’t reliably destroy all forms of life such as bacterial spores. Alcohols, like ethanol or isopropanol, are widely used as disinfectants because they rapidly denature proteins and disrupt cell membranes, providing quick broad-spectrum activity against many bacteria and enveloped viruses. They’re effective for surface and instrument disinfection and for hand sanitizing when formulated appropriately, though they aren’t sporicidal and won’t sterilize equipment that may harbor spores. The other options are more associated with sterilization or high-level disinfection under controlled conditions: aldehydes (including formaldehyde) and related compounds are used as potent sterilants and fixatives, and peracetic acid is employed as a high-level disinfectant/sterilant in specialized settings. Thus, alcohols best fit the common definition of a disinfectant in routine use.