Which disinfectant is toxic to cats?

• A. Bleach
• B. Phenols
• C. None of these
• D. Quats

Answer: (B)

Phenolic disinfectants are particularly dangerous to cats because felines metabolize phenols poorly. Cats lack sufficient detox pathways, so exposure to phenol-containing products can lead to severe toxicity, affecting the liver and kidneys after skin contact, inhalation, or ingestion during grooming. For this reason, phenol-based cleaners (like many cresol-containing products) are avoided around cats, even in small amounts or short exposures.

In comparison, diluted bleach is irritating and must be used with caution (good ventilation, thorough rinsing, and keeping the animal away until dry), but it does not pose the same specific feline metabolic risk as phenols. Quats are generally considered less problematic for cats, though ingestion or high concentrations can still cause irritation. The key idea is that phenols present a uniquely high risk to cats, making them the preferred answer.