Friday, Jul 24, 2026 The claims desk. Receipts included. POWERED BY LENZ ↗
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HEALTH

The Claim

Citronella oil has adulticidal effects on adult mosquitoes, other flying insects, and cockroaches.

Verified by Lenz ·

The Short Version

The evidence does not support this as a broad, general property of citronella oil. Stronger sources describe citronella primarily as a repellent, while some laboratory studies do show adult mortality in certain mosquitoes and other insects under specific conditions. The claim overstates that limited evidence and adds cockroaches without support from the cited record.

Caveats

  • Do not confuse repellency with adulticidal action: citronella is much better supported as an insect repellent than as an adult insect killer.
  • Laboratory toxicity results may depend on high concentrations, direct contact, fumigation, or specialized formulations and may not reflect ordinary real-world use.
  • The cockroach part of the claim is unsupported by the cited evidence, and 'other flying insects' is too broad for the available data.

The Receipts

  1. Oil of Citronella Fact Sheet

    National Pesticide Information Center

  2. Certain Essential Oils Found To Be Highly Effective at Killing Mosquito Larvae and Adults

    Beyond Pesticides

  3. The effectiveness of citronella essential oil extract as a mosquito ...

    University of South Florida Digital Commons

  4. Citronella – an overview

    ScienceDirect Topics

  5. Comparison of Repellency Effect of Mosquito Repellents for DEET and Citronella Oil

    PMC

  6. In vivo mosquito repellency effect of citronella (Cymbopogon nardus) essential oil bath bomb on Culex quinquefasciatus in dogs

    PubMed Central

  7. The effect of lemongrass (Cymbopogon nardus) extract as insecticide against Aedes aegypti

    Academia.edu

  8. Biological and Insecticidal Effect of Citronella Oil: A Short Review

    Academia.edu

  9. Efficacy of Active Ingredients From the EPA 25(B) List in Reducing Mosquito Biting Activity

    Journal of Medical Entomology (Oxford Academic)

  10. Citronella Oil - Uses, Side Effects, and More

    WebMD

+ 16 more sources — see the full list on Lenz

Filed Under

Citronella OilCockroachesMosquitoes

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