Question

Which of the following is Non-ester Pyrethroid?

• A. Etofenprox
• B. Allethrin
• C. Cypermethrin
• D. Deltamethrin

Hint:

Etofenprox is widely used in mosquito control programs due to its low mammalian toxicity.

Answer 1

The Correct Option is A

Step 1: Pyrethroids ending in "-thrin" (Allethrin, Cypermethrin, Deltamethrin) are ester-linked compounds.
Step 2: Etofenprox has no ester bond, it uses an ether linkage instead, making it esterase-resistant.
Step 3: Since only Etofenprox lacks the ester group, the correct answer is Etofenprox.