Which statement about pyrethroids is true?

Which statement about pyrethroids is true?

• A. They are never used in consumer products
• B. They degrade instantly in all conditions
• C. They have high mammalian toxicity
• D. They have low mammalian toxicity but cats are more sensitive

Answer: (D)

Pyrethroids are designed to be insect-specific in their action, and overall they are relatively safe for mammals because most mammals detoxify them quickly. The important nuance is species differences: cats are more sensitive to pyrethroids because they have limited capacity to metabolize and detoxify these compounds, especially certain pyrethroids, due to reduced glucuronidation and other liver enzyme activities. This means that while a typical exposure may be low-risk for most mammals, cats can experience neurotoxic effects like tremors, ataxia, and seizures at doses that wouldn’t affect humans or dogs as readily. That combination—low general mammalian toxicity with greater sensitivity in cats—is why the statement is true. Other options aren’t correct because: pyrethroids are commonly found in consumer products (pets, household sprays, and pest-control products), so they aren’t never used in consumer products. They do not degrade instantly in all conditions; they can persist indoors and outdoors depending on formulation and environment. And they do not have high mammalian toxicity; their relatively low mammalian toxicity is a defining feature, with the important caveat of cat sensitivity.

Pyrethroids are designed to be insect-specific in their action, and overall they are relatively safe for mammals because most mammals detoxify them quickly. The important nuance is species differences: cats are more sensitive to pyrethroids because they have limited capacity to metabolize and detoxify these compounds, especially certain pyrethroids, due to reduced glucuronidation and other liver enzyme activities. This means that while a typical exposure may be low-risk for most mammals, cats can experience neurotoxic effects like tremors, ataxia, and seizures at doses that wouldn’t affect humans or dogs as readily. That combination—low general mammalian toxicity with greater sensitivity in cats—is why the statement is true.

Other options aren’t correct because: pyrethroids are commonly found in consumer products (pets, household sprays, and pest-control products), so they aren’t never used in consumer products. They do not degrade instantly in all conditions; they can persist indoors and outdoors depending on formulation and environment. And they do not have high mammalian toxicity; their relatively low mammalian toxicity is a defining feature, with the important caveat of cat sensitivity.