Pyrethroids Medium Risk

Synthetic insecticides modeled after pyrethrins found naturally in chrysanthemum flowers. More persistent and potent than natural pyrethrins. Common in household insect sprays, pet flea products, and mosquito control.

Health Concerns

  • Neurotoxic effects on nervous system
  • Respiratory irritation when inhaled
  • Skin sensitization and allergies
  • Possible endocrine disruption
  • Toxic to cats (lack enzyme to metabolize)
  • Associated with behavioral effects in children

Environmental Impact

  • Highly toxic to aquatic organisms
  • Toxic to bees and beneficial insects
  • Can persist in sediments
  • Contaminates urban waterways
  • Harms aquatic food chains

Regulatory Status

Registered for use by EPA. Some restrictions on aquatic applications. Cat-specific warnings required.

What to Avoid

Permethrin, cypermethrin, deltamethrin, bifenthrin. Never use dog flea products on cats.

Safer Alternatives

Essential oil-based repellents, flea combs, food-grade diatomaceous earth, regular vacuuming for fleas

Products That May Contain This Chemical

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