Diffusion & Inhalation of Essential Oils + Scientific Aromatherapy Safety

January 13th 2021

by Amy Pereira – Educational Director, Pranarom USA

As Winter settles in, many of us will hunker indoors throughout the colder months and increase our use of essential oils, and products that contain them, to clean homes and workspaces, to impart welcome aromas (think cinnamon, clove, vanilla, and winter greenery), and to support respiratory and immune system health. But is it ‘sky’s the limit’ with regard to diffusing and overall exposure? This article explores these aspects of scientific aromatherapy and aims to shed light on some other common health and safety concerns.

According to market research and business projections, the global essential oil diffuser market expects a compound annual growth rate of anywhere from nearly 8 to 12 percent during a forecast period of 2020 to 2026. Although nebulizers are projected as the fastest-growing type of diffusing devices, ultrasonic types are expected to dominate, overall, because of factors such as their affordability, esthetic value, and use of radio wave technology to disperse the essential oils’ quickly, efficiently, and without heat. Regardless of the style of diffuser that is chosen, more and more households will seek them for their valued ability to effectively deliver the precious, therapeutic properties of essential oil molecules into the environment which, in turn, may enhance mood, help combat microbes that compromise air quality, and confer numerous other benefits.

With ever-increasing amounts of research and awareness surrounding scientific aromatherapy’s efficacy for mental health, stress and pain management, respiratory support, and more comes a substantial increase in essential oil usage within the natural products, spa, complementary/alternative, and mainstream medical industries (among others). But despite such an abundance of scientifically validated data, there is still a need to be mindful surrounding the safety of dispersing too many volatile organic chemicals into the environment – particularly around those with chemical sensitivities and compromised respiratory systems. Most essential oils are gas-like liquids and can quickly evaporate to fill rooms (whole homes and workplaces too, if a diffuser is used and is rated for larger spaces). Considering this, individuals with chemical sensitivities and compromised respiratory systems should avoid entering poorly ventilated, enclosed spaces in which a powerful diffuser is continuously dispersing dozens of drops. Similarly, while a USDA Organic Eucalyptus, with its naturally high percentage of 1,8-cineole (~62%-72% of total phytochemicals within, depending upon species) may serve the majority of individuals in effectively expelling excess mucus and quieting cough, high amounts of this same phytochemical may incite too much movement too quickly for those with conditions like asthma or COPD.

Now, this is not to say that a drop or two of essential oil that contains this phytochemical or essential oil that has a lower percentage of this constituent (like Spike Lavender at just under 28% 1,8,-cineole) cannot ever be used by these individuals to impart benefit in particular situations. On the contrary, such sensitive individuals may find that essential oils with lower percentages of certain chemicals, like cineole or limonene, may be perfectly useful when diffused sparingly; fortunately, a little goes a long way and as little as a drop or two in a diffuser with intermittent feature (which pulses on and off approximately every 30 seconds)– in a setting with good airflow– may be plenty to help promote a sense of ease, address microbes, assist with respiratory health, etc. without presenting health challenges or exacerbating existing ones. Further, certain essential oils that are commonly utilized to assist with skin issues, muscle, and joint care, and other specific conditions, may still be used by sensitive souls whether applied sparingly in neat fashion or to larger surface areas in diluted form and whether used as single notes or as part of a blend (when judiciously used in well-ventilated spaces).

For those in top health, without any chemical sensitivities or respiratory concerns, it is still always wise to tread lightly, respecting each drop and the significant amount of precious plant chemistry within. That said, there are still instances in which a larger more significant amount of essential oil may be warranted. For instance, if someone with an illness was recently quarantined in a room or area of a home and has, since, moved to a different space but there is still concern about lingering contagion in their formerly occupied room/area, then diffusing a hearty amount of essential oils that are rich in phytochemicals with air deodorizing and antimicrobial effects may be a supportive sanitization approach. Although it is generally not prudent for any of us to sit next to a diffuser on continuous full blast all day every day, a number of essential oils like Lemon, Frankincense, Clove, and Oregano are known for their powerful micromanaging limonene, pinene, eugenol and carvacrol chemicals, respectively, may be useful when diffused in significant concentrations for longer stretches of time in small enclosed spaces – provided no small pets or individuals remain in the space for the extended duration. Other essential oils like Thyme, Bergamot, Eucalyptus, and Tea Tree may also serve great benefit against certain molds and microbes when used in proximity of these threats (ref. 3,4). Ideally, once the diffusing period is complete, the windows in the particular room may be opened to ventilate the space before reentering for a more hands-on traditional cleansing and wiping of surfaces.

When it comes to employing essential oils as chest/vapor rubs, this can be a wonderful approach to encouraging circulation and movement and supporting expectoration and respiration however certain essential oils should always be diluted and those high in 1,8-cineole should not be used anywhere in close proximity to babies’ faces. As an adult, with no lung conditions that warrant abstaining from essential oil inhalation, a properly diluted respiratory support blend (made from essential oils and carrier oil or purchased in pre-diluted, pre-formulated form) may be applied to the chest or rib cage a few times daily as a safe, effective way to help foster deep breathing and release of the mucus that impedes it. Steam inhalation, which is performed by placing a towel over the head to create a tent over a steaming bowl of hot water in which EOs are floating, typically ushers even more vapors to the lungs than being in a room with a diffuser so use this practice wisely, if needed, in times of deep congestion.

With regard to essential oil ingestion that is a whole other, sometimes controversial, subject. Although there is much misunderstanding and clearly understandable concern around internal use, there are 150 different essential oils on the Food and Drug Administration’s Generally Regarded as Safe (GRAS) list therefore many of us are already ingesting these in foods and beverages such as soups, lattes, and other grocery items. Nevertheless, sprinkling them in water or placing drops directly on the tongue is not suggested. This is where education, a scientific aromatherapist or practitioner who is well-versed in their use, and pre-diluted, pre-formulated supplements that are specifically designed for these purposes are vital. Essential oils should always be diluted into a carrier such as honey or olive oil prior to ingestion, and while most supplements are formulated with safety in mind there are a few instances in which certain essential oils may be contraindicated; for those with gastroesophageal reflux disease (GERD), peppermint may not be the best choice. Consulting with a practitioner who knows your health history should always be a consideration when including any new supplements into your regimen however, generally speaking, essential oils like lemon, lavender, and ginger are already in numerous food items on grocery store shelves and have a proven track record of safety. For more information on Essential Oil Ingestion, see Provender’s Winter 2018 article, Safe Internal Use of Essential Oil Supplements, and be sure to do your homework if and when approaching internal use.

All in all, when seeking ways to safely incorporate essential oils into your regimen, use respectful amounts of certified organic essential oils, consider ultrasonic diffusers with the ability to intermittently pulse off and on throughout the day, and place use your diffuser in a well-ventilated space to ensure ample fresh airflow. With regard to supplements, it is wise to work with your health care professional yet know that there are products like Pranarom’s new Mini-caps that are formulated to contain safely diluted levels of essential oils (37.5 mg of organic essential oil diluted in 42.5 mg organic/non-GMO sunflower seed oil per Mini-cap) and please remember that a little goes a long way! As for topical application, although some essential oils can be applied neatly, some must always–without exception–be diluted into a carrier prior to use. Despite the fact that there is no one size fits all rule for how much essential oil is enough or excess and how much dilution is required, there are numerous resources that outline details for every single note and chemotype. If you don’t already have a quality, professional aromatherapy publication that includes dilution guidelines and safety tips for each oil, then please feel free to reach out to Pranarom for a complimentary “Guidebook to Chemotyped Essential Oils” to reap the benefits of this pharmacist-written booklet, complete with recipes and a wealth of information to send you well on your way on your scientific aromatherapy and lifelong wellness journey!



  1. Global Aromatherapy Diffuser Market: Growth: Trends: Forecast. (n.d.). Retrieved December 08, 2020, from https://www.mordorintelligence.com/industry-reports/aromatherapy-diffuser-market
  2. Ltd, R. (2020, August). Global Aromatherapy Diffuser Market Analysis 2020. Retrieved December 08, 2020, from https://www.researchandmarkets.com/reports/5136900/global-aromatherapy-diffuser-market-analysis-2020
  3. Vimalanathan S et al. Anti-influenza virus activity of essential oils and vapors. American Journal of Essential Oils and Natural Products. 2014;2(1):47-53. Retrieved December 08, 2020, from https://www.essencejournal.com/pdf/2014/vol2issue1/PartA/8-565.pdf
  4. Pyankov QV et al. Inactivation of airborne influenza virus by tea tree and eucalyptus oils. Aerosol Science and Technology. 2012;46:1295-1302. doi: 10.1080/02786826.2012.708948 Retrieved December 08, 2020, from https://www.tandfonline.com/doi/full/10.1080/02786826.2012.708948


At Pranarom Scientific Aromatherapy, each and every one of our products begins with sustainably harvested organic plants that have been distilled or pressed into pure oils. As experts in Scientific Aromatherapy, we safely harness the active properties of plants for vibrant health and wellness. Some see small amber bottles; we see a world of plants. For more information on any of the products seen within, visit www.pranarom.us or call (952) 831-6776

For nearly 25 years, Amy Pereira has served numerous roles in the natural products industry. With a Bachelors’s Degree in Environmental Science, Amy is passionately committed to environmental & human health education & is currently National Educator for Pranarom Scientific Aromatherapy as well as a Certified Holistic Nutrition Consultant, Registered Yoga Teacher, Meditation Instructor, and seasoned Wedding Officiant.