As an Aromatherapist I use essential oils or EOs on a regular basis for therapeutic purposes (see previous article on Aromatherapy). I regularly blend essential oils to prepare body oils, perfume rollers, body sprays, bath oils, and many others (see previous article on Aromatherapy’s uses). I use these on myself as well as prepare them for clients to help support their health and wellness goals.
EOs are extracted from aromatic substances found in all parts of the plant including the seeds, leaves, flowers, fruits, stems, bark, and roots, through processes of distillation, expression, carbon dioxide extraction, and others.
The modern use of EOs in Aromatherapy began in the 1930’s in Europe, although in recent years there has been an increased interest in Aromatherapy, making it one of the fastest growing alternative or complementary treatments. But, EOs are more common than you may realize, and have been used for thousands of years in a variety of industries.
1. EOs in Fragrances
This use for EOs is perhaps the most expected one. Throughout history EOs have been used in fragrance and perfumery. Indians and Chinese have been using EOs to prepare incense and other aromatics for thousands of years. As far back as 4500 BC, Egyptians were using EOs for mummification and religious practices, to scent their hair and skin, particularly in the uncomfortable summer months, and as an ambience enhancer in banquets and gatherings (Petersen, 2014). The practice of fragrance eventually spread to the Greeks, Romans, and other parts of the world, and the perfumery industry blossomed several hundreds of years later in France. Today, we still use EOs in fragrance and perfumery for both commercial and household purposes. Products include ambience aromas, foul odor maskers, scents for food, scents for personal items, perfumes, fragrances, and sprays.
2. EOs in Food
Uses of EOs in foods also started several thousands of years ago by Greeks, Romans, and Egyptians. There are records that Chinese used EOs in ice creams, and many believe Marco Polo reintroduced the use of EOs in food in Europe when he returned from China (Brud, 2009). EOs were used not just for flavoring, but also as preservatives. Today EOs are used less for their preservative qualities, and instead to flavor and scent things like soft drinks, water, liquors, juices, dairy, ice creams, condiments, pickles, spices, sweets, confectionary items, baked goods, meats, breads, and processed foods. One of the most used EOs is orange (Citrus sinensis), with a global consumption at around 50,000 tons, used to make “soft drinks, sweets, and fragrances” (Brud, 2009, p. 847).
3. EOs in Cosmetics
In addition, EOs are used in cosmetics and beauty products, such as soaps, shampoos, lotions, scrubs, oils, creams, and serums. One of the most notable historical uses of lavender is in the production of Yardley’s soap, which is still used today (Brud, 2009). EOs are used for their scent, but also for their therapeutic benefits. It is common to see Epsom salts scented with lavender to induce more relaxation while taking a warm bath. EOs are being increasingly used to make products for consumers interested in natural and organic ingredients in place of chemicals and additives.
4. EOs in Home Goods
EOs are used in home goods such as candles, mouthwash, toothpaste, chewing gum, other oral care, toiletries, tobacco, and household cleaning supplies. Toothpaste can contain mint, cinnamon, spearmint, and fennel EOs (Petersen, 2014). Mentha arvensis or cornmint, which is consumed globally at around 25,000 tons, is used in “oral care, chewing gum, confectionary, fragrances, and menthol crystals” (Brud, 2009, p. 847). The most commonly found EO in tobacco is menthol (Petersen, 2014). The use of EOs for these varies from flavor and scent additives to therapeutic purposes. In fact, EOs are even used in pharmaceuticals. Many analgesics (pain-relievers) contain clove EO, decongestants contain eucalyptus, camphor, and mint EOs, and other medicines include orange and mint EOs (Petersen, 2014).
Similarly to the cosmetics industry, with the growing interest for natural and organic products, many companies are turning to EOs to aid their marketing efforts. The irony is that many products, particularly mouthwash, toothpaste, and chewing gum, have been using EOs for much longer than there has been consumer interest in natural and organic EOs. Colgate has been using it in their toothpaste since the 1800s (Brud, 2009).
5. EOs For Animal Care
EOs in Animal Feed
EOs are often added to animal feed for their antimicrobial properties as an alternative to traditional antibiotics. Oregano and other EOs have antimicrobial effects, and have been used in the feed of poultry and pigs to help treat these animals from various microbes (van Dijk, A., 2009). Clove EO was used on chickens as an alternative to an antibiotic growth promoter, due to its antiseptic, antimicrobial, analgesic, and anesthetic properties (Hernández, Juste, Zomeño, Moreno, & Peñalver, 2009). An EO blend food additive was tested on Holstein cows and proved to be effective in improving health, increasing body weight, and improving milking performance (Kung, Williams, Schmidt, & Lu, 2008).
EOs in Veterinary Medicine
EOs have been used in veterinary medicine through application on the animal skin, inhalation, or ingestion. Lavender EO can be applied to heal cuts and burns, and it can be used to help calm down hyperactive dogs. Fleas and ticks can be removed from dogs, cats, or horses by using citronella, lemongrass, cedarwood, or pine EOs (Husnu Can Baser & Franz, 2009). Not all EOs are effective on all animals. Douglas fir oil is attractive to deer and wild boar and floral oils are attractive to dogs. Peppermint oil repels mice, citronella oils repel cats and dogs, and a combination of “cedarwood, cinnamon, sage, juniper berry, lavender, and rosemary” repels snakes (Husnu Can Baser & Franz, 2009, p. 884)
EOs cannot be consumed by or applied on all animals. For example, cats should not be given EOs orally or ] topically because they cannot metabolize them. Wintergreen, Gaultheria procumbens, contains salicylates that are toxic to both dogs and cats (Husnu Can Baser & Franz, 2009).
It is important to consult a Veterinarian or animal specialist before using EO’s on pets and animals.
6. EOs in Agriculture
EOs such as lavender, thyme, clove, garlic, citronella, basil, mint, rosemary, lemongrass and others, are used in agriculture as biocides and insecticides. Garlic, coriander, aniseed, and basil EOs are used to protect plants from aphids, and spearmint, tansy, and pennyroyal offer protection against ants (Petersen, 2014). Thyme, clove, mint, and rosemary are organic alternatives to more conventional and toxic chemical pesticides for plants (American Chemical Society (ACS), 2009). The challenge is that because of the volatile quality of EOs, these natural pesticides need to be applied more often. They are also less potent, and conventional pesticides are still needed to act against large insects that attack food crops, such as caterpillars, grasshoppers, and beetles (ACS, 2009).
7. EOs Are Vital To The Plant’s They Come From
Aromatic substances, and thus EOs, are made in specialized cells or plant parts that are often isolated from the rest of the plant, because they occur in high concentration and can be toxic to the plant. The precise location varies by plant, season, developmental stage, environmental factors, and other conditions.
Rhind (2012) states that aromatic substances can repel predators and predatory insects. For instance, some plants produce phenolic compounds that snails do not like. Also, some species of mint produce pulegone that functions as a repellent. Aromatic substances can attract beneficial insects that may eat or attack other predatory insects or pests of the plant. This is the case of wintergreen, which contains methyl salicylate, and attracts preys that eat plant pests. Aromatic substances also offer protection to the plant and ensure moisture is retained within it, which is the case of cedarwood oil. Cedarwood oil protects and preserves the wood of its plant by retaining moisture and preventing insects from entering the tree (Petersen, 2014). Rhind (2012) also states that aromatic substances can prevent pathogens from growing on the plant, and produce antifungal, antiviral, and antimicrobial chemicals.
Aromatic substances can attract insects and animals to the plant’s flowers, such as bees, to ensure that pollination occurs. Animals may be attracted to the plant or fruit to help disperse seeds from the plant. Aromatic substances can also function as a communication tool between plants or between the plant and the environment. For example, when a caterpillar starts eating a plant, it will release aromatic substances to signal other parasites to help the plant, or inadvertently attract more predators (Rhind, 2012). Also, some aromatic substances are similar to pheromones. These can act as alarm signals or sex pheromones for insects. Plants may release compounds to hinder competing plants from growing. This is the case with thyme that produces compounds that prevent some species of grass from growing. Aromatic substances regulate temperature and transpiration. Volatile oils in leaves reduce the loss of water by blocking stomata or creating an additional layer that protects the leaves, particularly in hot and dry conditions.
Popular EOs are consumed at 500 to 50,000 tons globally per year, and can generate over 2 billion Euros in sales annually (Brud, 2009). With the increase in demand for EOs there is also growing concern over running out of EOs by depleting the herbs and plants that produce them. As a result, there is growing interest in sustainable practices for growing and cultivating aromatic plants.
As mentioned already, there is also more interest in organic, natural and ecological products, and consequently EOs. A word of caution for the consumer. Just because a product is labeled as “natural” or “organic” it does not mean that it is 100% natural or 100% organic. The FDA and USDA have different regulations on what percentage of ingredients in a product must be natural or organic. For example, unless an EO has a USDA label on it that states it is 100% organic, the consumer must assume that the EO they are buying contains only a portion of organic or even natural ingredients.
American Chemical Society. (2009). “Killer spices' provide eco-friendly pesticides for organic fruits and veggies. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/2009/08/090816170910.htm
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Hernández, P., Juste, V., Zomeño, C., Moreno, J. R., & Peñalver, P. (2009). Effect of dietary clove essential oil on poultry meat quality. Retrieved on July 11, 2016 from http://www.lidervet.com/eng/ensayo-campo-5.html
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Van Dijk, A. (2009). Essential oils and acids: synergy makes them work. Feed Mix, 17(1), 14-16.