Essential oils (EOs) are highly concentrated extracts derived from various parts of plants, obtained through processes like steam distillation or cold-pressing. This results in a product significantly more potent than the original plant material. The question of whether these substances are safe to consume is complex. The term “therapeutic grade” does not signify automatic safety for consumption, and ingesting essential oils requires extreme caution.
The Meaning of “Therapeutic Grade”
The designation “therapeutic grade” is a marketing term utilized by essential oil companies, not a regulated standard established by any independent governmental or scientific body. No official agency, such as the FDA or the ISO, defines or certifies an essential oil as “therapeutic.” This means the term is primarily a promise of purity and quality made by the producer, rather than a universally recognized classification.
The actual quality of an essential oil depends on its chemical composition, verified through rigorous third-party testing. A reputable company provides a batch-specific analysis (often a Gas Chromatography/Mass Spectrometry (GC/MS) report) to confirm the oil’s purity and chemical profile. This testing ensures the oil contains expected active compounds and is free from synthetic additives, pesticides, or adulterants.
Without independent chemical verification, the “therapeutic grade” label offers little assurance of quality or safety. The term is intended to differentiate a product from lower-quality fragrance or cosmetic-grade oils. However, it fails to provide the necessary scientific standard for internal use, meaning a label alone should never be the basis for deciding to ingest an essential oil.
Safety Standards for Internal Use
The internal use of essential oils requires professional guidance, typically from a certified aromatherapist or qualified medical practitioner, due to their highly concentrated nature. Essential oils are 50 to 100 times more concentrated than the compounds found in the whole plant. This extreme potency means that even a single drop contains the equivalent of many cups of herbal tea.
The FDA maintains a list of substances, including certain essential oils, that are Generally Recognized As Safe (GRAS). However, GRAS status applies specifically to their use as flavor additives in food products, not for therapeutic dosing. This means the oil is considered safe when consumed in minute, trace amounts used for culinary flavoring, which is vastly different from ingesting a few drops for a perceived health benefit.
For oils sometimes considered for internal use, the general recommendation is extremely high dilution, often limited to one or two drops per day for short periods. Essential oils must never be ingested “neat,” or undiluted, as they do not mix with water and can cause irritation to the mucous membranes of the mouth and esophagus. Instead, they must be properly diluted in a suitable carrier, such as a vegetable-based oil, to ensure safe passage through the digestive system.
Acute Toxicity and Adverse Reactions
Ingesting essential oils without proper knowledge or supervision carries significant risks of acute toxicity and adverse reactions. The highly concentrated chemical components can irritate or burn sensitive tissues upon contact. This is particularly true for mucous membranes, potentially leading to irritation or ulceration of the esophagus and stomach lining.
A major concern with internal misuse is hepatotoxicity (liver damage), which occurs because the liver metabolizes the concentrated compounds. For instance, essential oils rich in phenols, such as eugenol found in clove oil, can deplete the liver’s protective compounds and cause severe damage. Ingestion of as little as 10 milliliters of clove oil has led to near-fatal hepatic failure. Similarly, Pennyroyal oil contains pulegone, known to cause severe hepatic necrosis.
High doses of certain essential oils can also lead to neurotoxicity, affecting the central nervous system. Ketone-containing oils (e.g., camphor, thujone in Wormwood, or 1,8-cineole in Eucalyptus) can trigger adverse effects, including seizures, delirium, and coma. Because essential oils are hydrocarbons with low viscosity, there is a risk of aspiration into the lungs, which can cause chemical pneumonitis (inflammation of the lung tissue).
Safe and Approved Methods of Application
For individuals seeking to use essential oils, the two primary methods are inhalation and topical application, which are significantly safer than ingestion. Inhalation, or aromatherapy, involves using a diffuser to disperse the oil into the air or inhaling from a tissue. This method allows the volatile compounds to enter the bloodstream quickly through the respiratory system, often for emotional or respiratory support.
Topical application involves applying the essential oil to the skin, but it must be diluted in a carrier oil, such as jojoba or coconut oil. Dilution reduces the risk of skin irritation and sensitization; common dilution rates for adults range from 1% to 3%. This method is effective for localized issues like muscle discomfort or skin support, providing benefits without the significant risks associated with internal consumption.