Herbs and Essential Oils that Repel Insects

In the middle of Summer, the biting bugs are out in full force, such as mosquitos, ticks, and fleas.  We want to repel such pests, not just because of the resulting itch, but also to steer clear of the potential diseases such as Malaria and Lyme Disease that they may carry.  There are many synthetic sprays on the market to deter insects and arthropods, but they can contain toxic chemicals with both environmental and health concerns such as skin irritations, headaches, nausea, difficulty concentrating, and more.

In recent years, the repelling potential of various essential oils and herbs has been significantly studied, with hopeful results.  Further, it has been researched that combining certain essential oils together, or with other natural products such as vanillin or neem has shown a synergistic strength, being more effective that products made with just a single essential oil.  Many essential oils, such as citronella, eucalyptus, peppermint, palmarosa, balm mint bush, and lemongrass have shown repellent action, but usually have a shorter repelling time than some of the chemicals like DEET that are more toxic to humans, animals, and the environment.

When using natural repellent sprays, keep in mind that they may have to be applied more often.  Further, certain ingredients may be inappropriate for pets (especially cats), children, pregnant ladies, and those with other health concerns.  Investigate the safety guidelines of the ingredients used in a natural spray.  Always discontinue use if any irritation occurs.

Here are a few natural recipes to try at home:

Herbal Flea, Tick, Mosquitoe, and Biting Fly Bug Spray

Essential Oil Bug Spray Recipe

https://www.earthtokathy.com/mosquito-repellent-salve-draft/

Research

• Essential oils can be efficient, and safer repellents for humans and the environment.  In this mega analysis on insect repelling essential oils, Cymbopogon (lemongrass) spp., Ocimum (basil) spp. and Eucalyptus (eucalyptus) spp. are the most cited.  Key constituents cited include α-pinene, limonene, citronellol, citronellal, camphor and thymol.  From:  Nerio, L. S., Olivero-Verbel, J., & Stashenko, E. (2010). Repellent activity of essential oils: a review. Bioresource technology, 101(1), 372-378.
• In this double blind randomized study of over 4000 participants,  the use of a bed net treated with a natural insect repellent whose key ingredient was Eucalyptus maculata citriodon, was effective in repelling the mosquito that causes malaria. Hill, N., Lenglet, A., Arnez, A. M., & Carneiro, I. (2007). Plant based insect repellent and insecticide treated bed nets to protect against malaria in areas of early evening biting vectors: double blind randomised placebo controlled clinical trial in the Bolivian Amazon. bmj, 335(7628), 1023.
• Essential oils offer a variety of insect repelling and controlling actions with less toxicity.  From: Regnault-Roger, C., Vincent, C., & Arnason, J. T. (2012). Essential oils in insect control: low-risk products in a high-stakes world. Annual review of entomology, 57.
• Essential oils for pest control was reviewed.  From: Regnault-Roger, C. (1997). The potential of botanical essential oils for insect pest control. Integrated Pest Management Reviews, 2(1), 25-34.
• Phytochemical extracts from citrus fruit peels (Citrus sinensis, Citrus limonum,Citrus aurantifolia, Citrus reticulata and Citrus vitus) at a dilution of 20-25% applied topically on human volunteers repelled insects for 2-5 hours.  From:  Effiom, O. E., Avoaja, D. A., & Ohaeri, C. C. (2012). Mosquito repellent activity of phytochemical extracts from peels of citrus fruit species. Global J Sci Front Res Interdisc, 12(1).
• Geranium treated bed nets repelled malaria causing mosquitos.  From:  Alipour, H., Mahdian, S. M. A., Rami, A., Abad, M. O. K., Amin, M., & Dinparast, N. (2015). Excito-repellency effects of Pelargonium roseum wild (Geraniaceae) essential oil-treated bed nets on the malaria mosquito, Anopheles stephensi Liston, 1901 (Diptera: Culicidae).
• Constituents of geranium oil demonstrated safe repelling action against the mosquito associated with the West Nile virus.  From:  Tabari, M. A., Youssefi, M. R., Esfandiari, A., & Benelli, G. (2017). Toxicity of β-citronellol, geraniol and linalool from Pelargonium roseum essential oil against the West Nile and filariasis vector Culex pipiens (Diptera: Culicidae). Research in veterinary science, 114, 36-40.
• Curcuma longa (tumeric), Citrus hystrix (lime), Cymbopogon winterianus (citronella), and Ocimum americanum (basil) were assessed for their repellency against three mosquito vectors, Aedes aegypti, Anopheles dirus and Culex quinquefasciatus.  Turmeric, citronella grass and hairy basil formulated with vanillin demonstrated mosquito repellency similar to deet.  From:  Tawatsin, A., Wratten, S. D., Scott, R. R., Thavara, U., & Techadamrongsin, Y. (2001). Repellency of volatile oils from plants against three mosquito vectors. Journal of Vector Ecology, 26, 76-82.
• Apium graveolens (celery), Citrus sinensis (orange), Eucalyptus globulus (eucalyptus), Juniperus oxycedrus (juniper), Laurus nobilis (bay), Lavandula hybrida (lavender) , Mentha microphylla (mint), Mentha viridis (spearmint), Ocimum basilicum (basil), Origanum vulgare (oregano), Pistacia terebinthus (turpentine tree), Rosmarinus officinalis (rosemary), and Thuja orientalis (thuja) were effective insect repellents against Acanthoscelides obtectus.  From:  Papachristos, D. P., & Stamopoulos, D. C. (2002). Repellent, toxic and reproduction inhibitory effects of essential oil vapours on Acanthoscelides obtectus (Say)(Coleoptera: Bruchidae). Journal of Stored Products Research, 38(2), 117-128.  Link:  http://dx.doi.org/10.1016/S0022-474X(01)00007-8
• Against the yellow fever mosquito, pulegone, thymol, eugenol, trans-anithole, rosemary oil and citronellal showed high larvicidal activity.  Eugenol, citronellal, thymol, pulegone, rosemary oil and cymene showed oviposition deterrent and/or repellent activities.  From:  Waliwitiya, R., Kennedy, C. J., & Lowenberger, C. A. (2009). Larvicidal and oviposition‐altering activity of monoterpenoids, trans‐anithole and rosemary oil to the yellow fever mosquito Aedes aegypti (Diptera: Culicidae). Pest management science, 65(3), 241-248.
• This was a review of neem ant its azadirachtin constituent and its repelling and insecticidal actions.  From:  Chaudhary, S., Kanwar, R. K., Sehgal, A., Cahill, D. M., Barrow, C. J., Sehgal, R., & Kanwar, J. R. (2017). Progress on Azadirachta indica based biopesticides in replacing synthetic toxic pesticides. Frontiers in plant science, 8, 610.
• Essential oils of Cymbopogan martinii (palmarosa), Cymbopogan citratus (lemon grass) and Cymbopogan nardus (citronella) were as effective as the chemical mylol in repelling mosquitoes. From:  Ansari, M. A., & Razdan, R. K. (1995). Relative efficacy of various oils in repelling mosquitoes. Indian journal of malariology, 32(3), 104-111.
• Field trials indicate that an aqueous cream containing 15% of the leaf oils of Litsea elliptica, Cinnamomum mollissimum, and Cymbopogon nardus provided 96.6% protection against mosquito bites.  From:  Jantan, I., & Zaki, Z. M. (1998). Development of environment-friendly insect repellents from the leaf oils of selected Malaysian plants. ASEAN Rev Biodivers Environ Conserv, 1-7.
• Essential oils from the following plants and their effectiveness as a mosquito repellent was reviewed:  Cymbopogon nardus, Eucalyptus maculata, Cymbopogon excavatus, Mentha piperita, and Azadirachta indica.  From:  Gupta, D. K., Chouhan, M., & Gupta, R. A. (2018). Herbal Mosquito Repellent Formulation from the Essential Oil: A Review. International Journal of Pharmacy & Life Sciences, 9(2).
• Peppermint oil on human skin was effective against three mosquito species.  From:  Ansari, M. A., Vasudevan, P., Tandon, M., & Razdan, R. K. (2000). Larvicidal and mosquito repellent action of peppermint (Mentha piperita) oil. Bioresource Technology, 71(3), 267-271.  Link:  http://dx.doi.org/10.1016/S0960-8524(99)00079-6
• The constituent cis-jasmone detracted aphids and attracted insects that ate aphids.  From:  Birkett, M. A., Campbell, C. A., Chamberlain, K., Guerrieri, E., Hick, A. J., Martin, J. L., … & Poppy, G. M. (2000). New roles for cis-jasmone as an insect semiochemical and in plant defense. Proceedings of the National Academy of Sciences, 97(16), 9329-9334.
• The constituent lavandulol has also been found in the pheromones of mealybugs (Planococcus kraunhiae) and can aid in mating disruption.  From:  Tabata, J., Teshiba, M., Shimizu, N., & Sugie, H. (2015). Mealybug mating disruption by a sex pheromone derived from lavender essential oil. Journal of Essential Oil Research, 27(3), 232-237.
• Methyl salicylate controlled release increased the amount of predatory insects (Chrysopa nigricornis, Hemerobius sp., Deraeocoris brevis, Stethoruspunctum picipes, Orius tristicolor) and may be useful in the growing of grapes and hops.  From:  James, D. G., & Price, T. S. (2004). Field-testing of methyl salicylate for recruitment and retention of beneficial insects in grapes and hops. Journal of chemical ecology, 30(8), 1613-1628.
• Methyl salicylate and myrtenal were repellent to the black bean aphid.  From:  Hardie, J., Isaacs, R., Pickett, J. A., Wadhams, L. J., & Woodcock, C. M. (1994). Methyl salicylate and (−)-(1R, 5S)-myrtenal are plant-derived repellents for black bean aphid, Aphis fabae Scop.(Homoptera: Aphididae). Journal of Chemical Ecology, 20(11), 2847-2855.
• Essential oils of Eucalyptus globulus, Lavender officinalis, Rosemarinus officinalis, and Thymus vulgaris showed repellent activities against the mosquito: Culex pipiens pallens.  Thyme was the strongest and constituents that were effective included alpha-terpinene, thymol, p-cymene, carvacrol, and linalool.  From:  Choi, W. S., Park, B. S., Ku, S. K., & Lee, S. E. (2002). Repellent activities of essential oils and monoterpenes against Culex pipiens pallens. Journal of the American Mosquito Control Association, 18(4), 348-351.
• This study warrants further research of the use of the following plant essential oils to repel insects such as the mosquitos Culex quinquefasciatus and Anopheles minimus:  citronella, hairy basil, catnip, and vetiver.  From:  Tisgratog, R., Sanguanpong, U., Grieco, J. P., Ngoen-Kluan, R., & Chareonviriyaphap, T. (2016). Plants traditionally used as mosquito repellents and the implication for their use in vector control. Acta tropica, 157, 136-144.
• A product whose main ingredient was celery seed oil was effective in repelling mosquitoes.  From:  Tuetun, B., Choochote, W., Pongpaibul, Y., Junkum, A., Kanjanapothi, D., Chaithong, U., … & Pitasawat, B. (2009). Field evaluation of G10, a celery (Apium graveolens)-based topical repellent, against mosquitoes (Diptera: Culicidae) in Chiang Mai province, northern Thailand. Parasitology research, 104(3), 515-521.
• Angelica archangelica root showed mosquito deterrent activities.  From:  Wedge, D. E., Klun, J. A., Tabanca, N., Demirci, B., Ozek, T., Baser, K. H. C., … & Zhang, J. (2008). Bioactivity-guided fractionation and GC/MS fingerprinting of Angelica sinensis and Angelica archangelica root components for antifungal and mosquito deterrent activity. Journal of agricultural and food chemistry, 57(2), 464-470.
• The following plant oils showed repellent activity against the mosquito Aedes aegypti:  Acantholippia seriphioides, Achyrocline satureioides, Aloysia citriodora (lemon verbena), Anemia tomentosa, Baccharis spartioides, Chenopodium ambrosioides, Eucalyptus saligna, Hyptis mutabilis, Minthostachys mollis (mint), Rosmarinus officinalis (rosemary), Tagetes minuta and Tagetes pusilla (marigold). From:  Gillij, Y. G., Gleiser, R. M., & Zygadlo, J. A. (2008). Mosquito repellent activity of essential oils of aromatic plants growing in Argentina. Bioresource technology, 99(7), 2507-2515.  Link:  http://dx.doi.org/10.1016/j.biortech.2007.04.066
• Pulegone, thymol, eugenol, trans-anithole, rosemary oil, citronellal, and cymene showed high larvicidal, oviposition deterrent, and/or repellent activities against the denge fever mosquito.  From:  Waliwitiya, R., Kennedy, C. J., & Lowenberger, C. A. (2009). Larvicidal and oviposition‐altering activity of monoterpenoids, trans‐anithole and rosemary oil to the yellow fever mosquito Aedes aegypti (Diptera: Culicidae). Pest management science, 65(3), 241-248.
• Vitex agnus castus (monk’s pepper) was used as an effective six hour spray to keep away ticks, mosquitoes, biting flies and fleas.  From:  Mehlhorn, H., Schmahl, G., & Schmidt, J. (2005). Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious with  repellent against ticks, fleas, mosquitoes and biting flies. Parasitology research, 95(5), 363-365.
• A two percent neem oil mixed in coconut oil  applied to the skin of humans gave complete protection for 12 hours against the anopheline species of mosquito associated with malaria.  From:  Sharma, V. P., Ansari, M. A., & Razdan, R. K. (1993). Mosquito repellent action of neem (Azadirachta indica) oil. Journal of the American Mosquito Control Association, 9(3), 359.
• A 2% neem oil mixed in coconut or mustard oil provided 100% protection against teh sand fly: Phlebotomus argentipes.  From:  Sharma, V. P., & Dhiman, R. C. (1993). Neem oil as a sand fly (Diptera: Psychodidae) repellent. Journal of the American Mosquito Control Association, 9(3), 364-366.
• A 2% neem oil mixed in coconut oil was effective at repelling multiple mosquito species.  From:  Sharma, S. K., Dua, V. K., & Sharma, V. P. (1995). Field studies on the mosquito repellent action of neem oil. The Southeast Asian journal of tropical medicine and public health, 26(1), 180-182.
• DEET is found as a pollutant in aquatic environments all over the world.  From:  Costanzo, S. D., Watkinson, A. J., Murby, E. J., Kolpin, D. W., & Sandstrom, M. W. (2007). Is there a risk associated with the insect repellent DEET (N, N-diethyl-m-toluamide) commonly found in aquatic environments?. Science of the Total Environment, 384(1-3), 214-220.
• A review of 20,000 DEET related calls from Poison Control was reviewed.  From:  Bell, J. W., Veltri, J. C., & Page, B. C. (2002). Human exposures to N, N-diethyl-m-toluamide insect repellents reported to the American Association of Poison Control Centers 1993–1997. International journal of toxicology, 21(5), 341-352.

By: Kathy Sadowski, MS in Aromatherapy, Registered Aromatherapist, NAHA and AIA Member, LMT

4/11/18

This categorized compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use. These statements are not meant to diagnose, treat, or cure any diseases. The information at this page has not been evaluated by the Food and Drug Administration. Consult a Doctor before using herbs and essential oils if you have medical conditions, are taking medications, or have questions.