Although essential oils are natural substances, “natural” and “safe” have never been synonymous. Nature is replete with poisonous plants (deadly nightshade, wolf’s bane, foxglove, suicide tree, etc.) not to mention spiders, snakes, scorpions etc. Natural bitter almond oil even contains cyanide, though it has been illegal to sell this since 1890, unless the cyanide is first removed. Before that, buying a 1 oz bottle at a drug store was an easy route to suicide.
This is an extreme example, but there are many potential safety issues with essential oils. These include drug interactions, fetotoxicity, liver toxicity and neurotoxicity, but the most common and tangible safety issue is adverse skin reactions. And the most vulnerable group is children under 6 years of age.
We now have a plethora of research studies that show us how essential oils can be helpful, but also how they can be harmful. Sometimes the same action can be both – for example, oregano oil kills bacteria by disrupting the bacterial wall, but has a similar effect on skin cells, which manifests as skin irritation. In this type of scenario, dilution needs to be optimal, in other words we want the amount that will kill unwanted microbes but with a minimal skin irritation.
One challenge facing aromatherapy is the gradual increase of adverse events – adverse skin reactions or poisoning – that has accompanied the increase in popularity of essential oils. This, along with often baseless claims for treating serious disease, gives aromatherapy a bad reputation, and is a short-cut to increased regulation of essential oils, something that is already happening in Europe.
For example, “dilute with fractionated coconut oil” is not really good enough for certain oils. According to IFRA, clove oil should not be used at more than 0.5% and cinnamon bark oil should not be used at more than 0.1% for products such as body oils and body lotions. In a 2015 Tisserand Institute survey we found that 17% of respondents who topically applied diluted cinnamon bark oil reported having an adverse reaction. Most of them had not diluted the oil sufficiently.
Figure 1 shows the number of adverse incidents from essential oils that were reported to poison centers in the USA. Most of these were not serious, and most were accidental, but they show a worrying upward trend for children under 6, compared with older children or adults. This suggests that young children are becoming “victims” of the growth of the aromatherapy industry, which is now worth several billion dollars per year worldwide.
For children under 6, a large number of incidents come from accidental essential oil ingestion, and these are totally preventable. Essential oils should never be handled by young children, should always be kept in a place they cannot reach, and child-proof bottle caps should be a requirement for all essential oils.