All are true regarding disinfectants except -a) Gluteraldehyde is sporicidalb) Hypochlorites are virucidalc) Ethylene oxide is intermediate disinfectantd) Phenol usually requires oganic matter to act

**Core Concept**
Disinfectants are chemical agents used to eliminate or inactivate pathogens on inanimate surfaces. They are classified based on their spectrum of activity and mode of action. Understanding the properties and mechanisms of disinfectants is crucial in preventing the spread of infections in healthcare settings.

**Why the Correct Answer is Right**
Gluteraldehyde is indeed sporicidal, making it effective against bacterial spores, which are highly resistant to disinfection. Hypochlorites, such as bleach, are virucidal, meaning they can inactivate or kill viruses. Ethylene oxide is used as a sterilant, not a disinfectant, and is effective against bacterial spores, viruses, and fungi, making it a high-level disinfectant or sterilant. Phenol and its derivatives, such as phenol-based disinfectants, can act in the absence of organic matter, as they can denature proteins and disrupt cell membranes.

**Why Each Wrong Option is Incorrect**
**Option A:** This statement is incorrect because the question asks for an exception, and gluteraldehyde is indeed sporicidal.
**Option B:** This statement is incorrect because hypochlorites are indeed virucidal.
**Option C:** This statement is incorrect because ethylene oxide is used as a sterilant, not a disinfectant, and is effective against a broader spectrum of microorganisms.

**Clinical Pearl / High-Yield Fact**
Phenol and its derivatives can be used as disinfectants in the absence of organic matter, making them effective against a wide range of microorganisms. However, they can be irritating to skin and mucous membranes, and their use requires proper handling and precautions.

**Correct Answer:** D. Phenol usually requires organic matter to act.