pyrethrin

insecticide

Also known as: pyrethrum

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Last updated

July 13, 2026

Quick Summary

Pyrethrins are natural insecticides derived from the flower heads of certain plant species in the aster family, such as the pyrethrum daisy. These compounds are effective contact poisons for insects and cold-blooded vertebrates.1

Pyrethrin insecticides are widely used in homes and for edible plants due to their low toxicity to plants, birds, and mammals. They are also a key component in organic farming. While generally safe for humans, pyrethrins can cause allergic contact dermatitis and asthma in some individuals.12

Synthetic compounds, known as pyrethroids, have been developed that mimic the insecticidal properties of natural pyrethrins. Both natural and synthetic pyrethrins can be toxic to fish and aquatic invertebrates if they accumulate in water.31

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poison
Insecticides
Pyrethrins are widely used insecticides in the home. They have a rapid “knockdown” for insects and have a low potential for producing toxicity in humans. The major toxicity of pyrethrins is allergy. Rotenone is a mild irritant and animal carcinogen (Table 1).
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Pyrethrins are widely used insecticides in the home. They have a rapid “knockdown” for insects and have a low potential for producing toxicity in humans. The major toxicity of pyrethrins is allergy. Rotenone is a mild irritant and animal carcinogen (Table 1).
Read More