Lemon Eucalyptus vs IR3535: Which EPA-Registered Repellent Fits?
IR3535 and oil of lemon eucalyptus (OLE) are both on CDC's list of recommended repellent ingredients, and both must come as EPA-registered products. The biggest practical difference is age: CDC says not to use OLE or PMD products on children under 3, while it says IR3535 products can be used on children without age restriction.
Lemon Eucalyptus Essential Oil
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Shop Now →That age rule is the first thing to settle, so it opens this page. The rest is a short, honest comparison built from CDC and EPA documents, plus a caution about protection times, because numbers for IR3535 vary a great deal by product. We sell neither a registered OLE repellent nor an IR3535 repellent. We sell lemon eucalyptus essential oil, which is not a registered repellent, so this page is a buyer's aid and not a pitch. Last reviewed: October 2026.
The two-line comparison
| Question | Oil of lemon eucalyptus (OLE) | IR3535 |
|---|---|---|
| On CDC's recommended list | Yes ("OLE or PMD") | Yes |
| EPA registration needed | Yes, for the repellent product | Yes |
| Children under 3 | CDC: do not use OLE or PMD products | CDC: can be used without age restriction (follow the label) |
| Registered product protection time | Per product label | Per product label; EPA's 2019 review of two 20% products supported 3 hours |
| Typical label cautions | Read the label for eye and age statements | Eye hazard statement; some labels warn about plastics and synthetic fibers |
| Where it sits for the essential oil we sell | Not the same material (see our comparison) | Unrelated |
CDC's active-ingredient list is on its mosquito-bite prevention page, and the age statements come from the CDC Yellow Book chapter on arthropods. For the five-way view that includes DEET, picaridin and 2-undecanone, use the ingredient comparison; the hub guide, oil of lemon eucalyptus explained, covers the OLE side.
Age is the deciding difference
If a child under 3 will be wearing the repellent, OLE and PMD are out by CDC's rule, and IR3535 is one of the ingredients CDC says can be used without an age restriction. That does not mean any IR3535 product is right for any child. Read the label of the exact product, because EPA-accepted labels add their own directions. On the EPA-accepted label for one 20% IR3535 aerosol (EPA Reg. No. 70759-4, label dated February 13, 2025), for example, the text says not to let children handle the product, not to apply it to children's hands, and to apply it to your own hands first and then put it on the child. For children under 2 months, EPA's repellent-safety page directs readers to a health care provider or the National Pesticide Information Center at 1-800-858-7378 (EPA). A pediatrician is the right person to ask about a specific baby; for the wider picture see lemon eucalyptus and kids.
One caution about that label: the document in EPA's database is a template with bracketed optional text, so some phrases below are optional claims that a given product may or may not carry. We are quoting the template for what an EPA-accepted label can say, not describing a retail product we have seen.
Protection time: why you cannot trust a single number
Here sources disagree, and the disagreement is instructive.
- EPA's 2019 science review of a Florida field study of two products, a lotion and a wipe, each containing 20% IR3535, concluded that the study supports a complete protection time of 3 hours for both. The applicant had argued for 14 hours; EPA did not accept that (EPA science review, October 2019).
- The optional text on the EPA-accepted aerosol label template reads "[Repels] [mosquitoes] [and] [ticks] [for] [up to] [8 hours]" and tells users to reapply about every 8 hours, not to exceed three applications a day (EPA label, 70759-4).
- A 2002 lab comparison in the New England Journal of Medicine of 16 repellents, as summarized by ScienceDaily, listed Skin-So-Soft products (IR3535 or citronella) as protecting for well under 20 minutes, with DEET products protecting for hours (ScienceDaily summary). The summary does not give the IR3535 concentration.
These are three different products, concentrations and test designs, so we do not average them. What they share is a lesson: for IR3535, the percentage and the product matter, and the number to trust is the one on the label of the product in your hand, backed by registration. We have not verified protection times for any specific OLE product for this page, so we do not compare hours directly. For the OLE-versus-DEET side of the argument, see lemon eucalyptus versus DEET, and for picaridin, lemon eucalyptus versus picaridin.
What OLE has that the IR3535 evidence does not
A fair comparison needs the other direction too. In a 2017 wind-tunnel study at New Mexico State University, a commercial lemon eucalyptus spray significantly reduced the attraction of Aedes aegypti mosquitoes to a volunteer, as did the DEET sprays; the authors wrote that "DEET and PMD are very effective mosquito repellents when used in sufficient concentration" (Rodriguez et al., 2017). That study did not include IR3535, so it cannot rank the two, and a lab attraction test is not a field protection time. A Malaria Journal review likewise calls PMD the only plant-based repellent advocated for use in disease-endemic areas by CDC (Maia and Moore, 2011). We read the evidence as: both are legitimate registered choices, OLE has more independent lab work behind it in the sources we opened, and IR3535 has the age advantage.
Label details that affect real use
- Eyes. The IR3535 label template carries a hazard statement that the product "causes substantial but temporary eye injury." Apply to the face by spraying onto your palm and rubbing on, as the template directs, and keep it away from eyes.
- Sunscreen. The template lists optional text: apply sunscreen first, wait 10 to 15 minutes, then apply the repellent. Check your own label, and ask a pharmacist if you use several skin products.
- Plastics and fabrics. The template lists optional text to avoid contact with plastics, costume jewelry, leather and synthetic fibers. This is a reason to read the label before gear, glasses or watch straps touch the product.
- Pest list. Check whether the label names mosquitoes only or also ticks. EPA's repellent search tool lets you filter by target pest, protection time and active ingredient.
Who should choose which
| You are | Lean toward | Reason |
|---|---|---|
| Applying to a child under 3 | IR3535 (or another ingredient CDC allows without age restriction), after asking a pediatrician | CDC rules out OLE and PMD under 3 |
| An adult who dislikes the scent of some repellents | Try a small amount of either product, following the label | Scent preference is personal; we have no scent data on either |
| Wearing synthetic gear or carrying a camera | Read the label of either product for plastics and fabric statements | Labels vary |
| Traveling to an area with mosquito-borne illness | Ask a travel-medicine clinic | This is a medical decision, not a label comparison |
Where we come in
Because our shop sells the essential oil and not these products, our recommendation is the same one CDC gives: choose a registered product, read its label, and ask a professional where illness is the concern. If what you want is the lemony top note of lemon eucalyptus for a candle, soap or diffuser, the shop page lists sizes from 0.5 oz upward. It is a fragrance material, and our stance page says plainly that it is not a registered repellent.
FAQ
Is IR3535 natural?
The EPA label template lists "Classified as a Biopesticide by the EPA" as an optional claim, but we did not find a source that settles how to describe its origin, and "natural" is not a safety test. Judge it by registration, label directions and the age rules above.
Is IR3535 safe for babies?
CDC says IR3535 products can be used on children without age restriction. For an infant, ask the pediatrician first and follow the label; a physician should answer any question about a specific child.
Can I use either one with sunscreen?
Some labels say to apply sunscreen first, wait 10 to 15 minutes, then apply the repellent. Follow your product's own label.
Which lasts longer?
It depends on the product. EPA's review supported 3 hours for two 20% IR3535 products, while label text on other products can state longer or shorter times. Compare labels, not ingredient names.
Where can I find registered products?
Use EPA's search tool and look for the EPA registration number on the label. Our guide to choosing a lemon eucalyptus repellent walks through label checks.
Lemon Eucalyptus Essential Oil
Lemon Eucalyptus Essential Oil from our own shop, in sizes from 0.5 oz to bulk.
From $9.99
Shop Now →Sources & Further Reading
- CDC: Preventing mosquito bites
- CDC Yellow Book: Mosquitoes, Ticks, and Other Arthropods
- EPA (2019): Science review of a field evaluation of two IR3535 products
- EPA-accepted label, Bug Repell IR3535 20% Aerosol (Reg. No. 70759-4)
- EPA: Using Insect Repellents Safely and Effectively
- EPA: Find the repellent that is right for you
- Rodriguez et al. (2017), Journal of Insect Science
- Maia and Moore (2011), Malaria Journal
- ScienceDaily: Comparative efficacy of insect repellents (Fradin and Day, NEJM 2002)