Essential oils: caution, real risks and rules for use at home
Essential oils are concentrated products, not harmless fragrances. Risks for skin, airways, children and animals, and rules of caution, with no dosage given.
Key points
| Nature | Highly concentrated plant extracts, complex mixtures of molecules |
|---|---|
| Main risks | Irritation, allergy, poisoning if swallowed, breathing discomfort when diffused |
| Vulnerable groups | Pregnant or breastfeeding women, young children, people with epilepsy or asthma, animals |
| Swallowing | Never without advice from a healthcare professional |
| On the skin | Never neat; seek professional advice before any dilution |
| Storage | Out of reach of children, away from heat and any flame |
| In case of accident | 15 or 112, or a poison control centre; do not induce vomiting |
What essential oils are, and are not
An essential oil is an aromatic extract obtained by steam distillation or by pressing (for citrus fruits). Despite its name, it is not a fatty oil: it is a concentrate of volatile molecules. Sometimes several dozen kilos of plant material are needed for a bottle of a few millilitres. These extracts are complex mixtures whose composition varies with the plant, the part used, the climate and the harvest date. The French health agency (ANSES) points out that many products labelled “essential oil” also contain large amounts of other ingredients, such as ethanol in sprays or a vegetable oil in massage products.
“Natural” does not mean “risk-free”: hemlock is also entirely natural. We give no dosage and no recipe here, because the right approach depends on the person and the product, and is a matter for a professional (doctor, pharmacist, qualified aromatherapist).
The risks, one by one
| Risk | Explanation |
|---|---|
| Swallowing | Can cause serious poisoning, especially in children; some oils (tea tree, niaouli, cajuput) have neurological effects described by ANSES |
| Contact with the skin | Irritation, burns, allergy; a neat oil can cause lasting sensitisation |
| Mucous membranes and eyes | Never apply neat |
| Diffusion and sprays | Exposure through indoor air, with a possible effect on breathing; oils rich in phenols or ketones are considered irritating to the airways |
| Photosensitisation | Cold-pressed citrus oils (such as bergamot) can cause skin reactions in sunlight |
| Allergens | Linalool, limonene, geraniol, citronellol and other molecules must appear on the labels of fragranced products in the European Union |
| Flammability | Oils catch fire easily: never near a flame, a candle or a charcoal disc |
Who should take particular care?
- Pregnant and breastfeeding women: ANSES advises against essential oils during pregnancy, as some substances may be toxic to the embryo or foetus.
- Children: oils are not recommended for children, as some molecules are neurotoxic. ANSES recommends banning niaouli and cajuput oils for children under 30 months and for those with a history of seizures. Oils must never be applied near the nose of an infant.
- People with epilepsy or asthma: some oils (rosemary, sage, eucalyptus, mint) should be avoided or used only on medical advice.
- Animals: cats, dogs, birds, rabbits and reptiles react badly to many oils. Veterinarians point out in particular the sensitivity of cats, which clear several compounds poorly. Do not diffuse oils around them, and let them leave the room.
Rules of caution for the home
- Consult a healthcare professional before using essential oils, especially if you have an illness, are on treatment, or are pregnant.
- Read the label: Latin name of the plant, part used, chemotype, batch number, precautions for use.
- Do not swallow them and do not give them to a child.
- Do not apply them neat to the skin or mucous membranes. Wash your hands after contact.
- Avoid prolonged diffusion in a closed room; ventilate well when using a diffuser or spray, as ANSES recommends.
- Store bottles out of reach of children, away from medicines and infant care products: ANSES found that, in roughly a third of accidents involving children, an essential oil had been given by mistake in place of a medicine (often vitamin D).
- Do not add oil to a candle, a charcoal disc or a fire.
Calls to make in case of accident
If swallowed, splashed into the eye, or if you feel unwell, do not induce vomiting, keep the bottle and its label, and call 15 (SAMU in France) or 112 (the emergency number across the European Union), or a poison control centre. For an eye, rinse thoroughly with clean water and seek medical advice. According to ANSES, calls to poison control centres about essential oils rose steadily from 2011 to 2021; most concern minor household accidents, but some are serious.
And the plants themselves?
In our plant sheets (lavender, mint, eucalyptus, thyme, sage), the dried plant, used for decoration or in sachets, does not carry the same risk profile as the concentrated oil. But smoke, whatever the plant, contains particles: see Fire safety and rituals. For scented incense, see Incense and fumigation.
Frequently asked questions
Can I put essential oils on a candle?
No: they are flammable and can make the candle flare up. Choose candles already scented by a manufacturer.
Are essential oils safe because they are natural?
No. Many are irritating, allergenic or toxic if swallowed. Natural does not mean risk-free.
Can I diffuse essential oils around a baby or a cat?
It is better to avoid it. ANSES advises against oils for young children; cats are particularly sensitive. Ask your paediatrician or veterinarian for advice.
What should I do if a child has swallowed essential oil?
Do not induce vomiting. Call 15 or 112 immediately, or a poison control centre, showing them the bottle.
Why do you not give any dosage?
Because the right amount depends on the person and the product, and that decision belongs to a healthcare professional.
Also read
The meanings mentioned belong to tradition and symbolism. They are neither promises of results nor medical advice. Back to Herbs, waxes and accessories.