Which of the following is a plausible safety concern when using pyrethrin products?

• A. It can be toxic if overdosed
• B. It never causes any adverse effects
• C. It improves liver function
• D. It repels fleas but does not kill them

Answer: (A)

The main safety idea here is that even natural insecticides can be dangerous if they’re not used exactly as directed. Pyrethrins work by affecting the nervous system of insects, but that same mechanism can harm pets if the product is overdosed or misused. Overdosing a pyrethrin product can lead to toxicity, with signs such as tremors, drooling, ataxia, weakness, or even seizures in more severe cases. Cats are especially sensitive, and risk rises if an animal grooms after application or if multiple products are used together or not rinsed off as instructed. That’s why overdosing is the plausible safety concern. The other statements don’t fit as safety concerns: pyrethrins can cause adverse effects, so saying they never cause problems is incorrect; they don’t enhance liver function—this isn’t how they work; and while some formulations may have repellency, many products are intended to kill fleas, so stating they only repel and don’t kill isn’t accurate or relevant to safety.