In a groundbreaking study led by Acadia University, researchers have gained a better understanding of how lemongrass essential oil significantly impairs the ability of blacklegged ticks to detect humans. The findings published in Current Research in Insect Science by Dr. Nicoletta Faraone, Dr. Luis Anholeto, Dr. Kirk Hillier, and master’s graduate Kayla Gaudet, could pave the way for more effective, natural tick repellents and offer a safer alternative to synthetic chemicals like N,N-diethyl-meta-toluamide (better known as DEET).

Blacklegged ticks are notorious for carrying Lyme disease and other pathogens that can cause debilitating diseases in humans. These insects rely heavily on their olfactory systems to locate hosts. In fact, blacklegged ticks have no eyes and depend almost exclusively on smell to find nourishment.

The study found that exposure to lemongrass essential oil disrupts the ticks’ ability to detect human scents, effectively “blinding” them to potential hosts. The research conducted at Acadia University—which included ticks confirmed to be carrying Lyme disease—revealed that lemongrass oil offers a dual benefit: in addition to masking attractive scents emitted by humans (like carbon dioxide and butyric acid), the oil has a repelling effect that makes us unappetizing.

Dr.  Nicoletta Faraone, an associate professor in Acadia University’s chemistry department, led the research. She explains the significance of the results generated by her team and how they point to practical solutions people could use in their everyday lives.

“Ticks exposed to lemongrass oil are less likely to crawl on you, and even if they’re brave enough to do so, they’re far less likely to bite,” says Dr. Faraone. “The tick is likely to be repelled or become so disoriented that it drops off.”

One of the most exciting aspects of this research is the potential for lemongrass oil to serve as a natural alternative to DEET, the most commonly used synthetic repellent. While DEET is effective, it has been linked to environmental and health concerns, including toxicity to aquatic life and potential skin irritation in humans.

“Lemongrass oil is not only effective, but also environmentally friendly,” says Dr. Faraone. “It’s a win-win for those looking to protect themselves from ticks without the drawbacks of synthetic chemicals.”

For the average person, this finding could mean safer, more natural options for tick protection. And a bonus: lemongrass essential oil has been found to repel mosquitos, too.

But before you run out and start drenching everyone in the natural oil, Dr. Faraone stresses that her study took place in a controlled lab environment, and the results may not be replicable out in the woods.

Still, diluted or formulated versions of lemongrass essential oil are largely considered safe and beneficial for most people, says Dr. Faraone. “But they should be tested on a small patch of skin first to make sure they don’t cause any irritations or reactions.”

In fact, some essential oils can be toxic to family pets, including cats and dogs, so owners should consult a veterinarian before using any repellent around animals.

Acadia University’s tick research has already had a tangible impact on the local community’s well-being thanks to a collaboration with AtlanTick Repellent Products, a Nova Scotia-based company that provides natural tick and insect protection for families and pets.

The relationship has been cultivated by Acadia’s Office of Industry and Community Engagement in an effort to help local businesses generate financial, economic, academic and societal benefits for regional communities. Dr. Faraone has been involved since 2017 in developing and optimizing AtlanTick’s natural repellent formulations, including helping to ensure the products meet Health Canada’s rigorous safety and efficacy standards. Today, Dr. Faraone and her team continue to explore new products and expand applications and formulations of the AtlanTick brand.

These efforts are just a few pieces of a bigger picture that is putting Acadia University at the forefront of tick research. It’s work that is gaining importance as tick populations and instances of Lyme disease are on the rise.

Dr. Faraone and her team have begun to explore the chemosensory systems of ticks in greater depth, including those of other tick species found in the Maritimes. Through funding provided by an NSERC Discovery Grant along with NSERC Alliance and Mitacs Accelerate grants (with matching funds from AtlanTick), Dr. Faraone and her talented post-doc, Dr. Luis Anholeto are now investigating how environmental conditions like temperature and humidity influence tick behaviours in order to gauge the possible effects of a warming climate. This ongoing research could lead to even more effective tick control strategies in the future.

This article was adapted and published with permission from Acadia University.