Why I Do Not Use Essential Oils in Client Homes

Most natural cleaning ranges are built on citrus and lavender. It is the first thing you smell in the aisle, and for a lot of people it is the reason they believe they have switched to something gentler. I do not use essential oils in client homes, and I get asked why often enough that the answer deserves more than a single line on a service page.

Fragrance is a category, not a single ingredient

A product is fragranced when something has been added to make it smell like something. Where that something came from does not change the category. Steam-distilling lavender flowers gives you a concentrated mixture of aromatic compounds, most of them terpenes and terpene alcohols. A perfumer's lab gives you a concentrated mixture of aromatic compounds too. The plant version is more chemically complex, not less.

So a bottle labelled "no synthetic fragrance" is telling the truth. It is just not making the claim most people hear. Fragrance-free and naturally fragranced are different products, and the gap between them is the whole reason this article exists. It is also the most common point of confusion across the natural and eco cleaning products sold in Australia, where the marketing language has drifted a long way from the ingredient list.

Volatile is the entire mechanism

The word describes a compound that evaporates readily at room temperature, and that property is exactly what makes an oil smell like anything at all. If you can smell lemon myrtle from across the kitchen, the molecules are no longer in the bottle. They are in the air you are breathing, and they stay there until the room is ventilated or they react with something.

That last part is worth sitting with. Terpenes such as limonene and pinene react with ozone in indoor air, and those reactions generate secondary products including formaldehyde and very fine particles. Most of that work has been done in test chambers rather than in real Brisbane homes, and the concentrations vary enormously with ventilation, how much product was used and what else is in the air. I am not going to tell you a diffuser is dangerous, because the honest answer is that the exposure in an ordinary well-aired house is probably small. What I will say is that the compound does not simply vanish because it smelled nice on the way out.

Plant-derived is not the same as inert

Concentration decides almost everything here. A neat essential oil is a potent material. Applied undiluted to skin, several will cause irritation or a chemical burn, which is why every reputable aromatherapy source insists on carrier dilution. Cleaning products dilute them far further, so the comparison is not direct. But the compounds themselves are not gentle by nature, and "natural" carries no information about how a substance behaves on skin or in airways.

The regulatory position is instructive. The European Union requires named fragrance allergens to be declared on cosmetic labels once they exceed low concentration thresholds. The original list ran to 26 substances and was expanded considerably in 2023, and a large share of it is plant-sourced: limonene from citrus peel, linalool from lavender and rosewood, geraniol, citral, eugenol from clove, coumarin from tonka. Those are not obscure ingredients. They are the backbone of the pleasant-smelling natural cleaner category.

Sensitisation is also cumulative, and it rarely reverses. Someone can use a product happily for 2 years and then start reacting to it, and once that happens the reaction usually persists. That is part of the reason I would rather not introduce a new aromatic compound into a house I clean fortnightly, which is a long exposure schedule by any measure. If you want to work out what is actually in the bottles under your own sink, reading a cleaning product label properly is a better use of an afternoon than most people expect.

The cat problem, which is not a small one

Cats have limited capacity for glucuronidation, a liver pathway most mammals rely on to process phenolic compounds. Tea tree oil is the most documented example, and veterinary case reports of cats becoming seriously unwell after skin application or spills are not rare. Pine, wintergreen, citrus and eucalyptus oils come up as well.

The exposure route in a cleaned house is not dramatic. A cat walks across a floor mopped with an oil-containing product, then grooms its paws. Or a diffuser runs in a closed room the cat sleeps in. I am not a vet and this sits outside my scope, so if you have a cat and you use oils anywhere in the house, that is a conversation to have with your own vet rather than with a cleaner. It is enough of a risk that I will not make the decision on a client's behalf in a home I do not live in.

The antimicrobial argument, taken seriously

This part deserves fairness, because the research is real. Tea tree, oregano, thyme and clove oils all show measurable antimicrobial activity in laboratory conditions. Some of it is genuinely impressive on paper.

Then you look at how that translates to a bucket. Lab work uses defined concentrations, direct contact and controlled time. A domestic mop solution is a capful in 5 litres, spread across 40 square metres of floor, evaporating as it goes. Oils are also not water-soluble, so without a surfactant to disperse them they sit on the surface of the water rather than mixing through it. Contact time is seconds. There is no residual effect once the floor dries.

None of that means the floor is not clean. It means the cleaning came from the detergent, the agitation and the water, not the oil. If disinfection is the actual requirement, after raw chicken or during illness in the house, use a product registered for that purpose and honour the contact time on the label. I have written more on where the line sits between cleaning and disinfecting in do natural cleaners actually disinfect.

Why I hold the line in someone else's home

In my own house I could make a judgement call. In a client's house I cannot, because I do not know everyone who lives there or visits. There may be a baby, a cat, or someone who reacts to fragrance and has spent years working out which products they can tolerate.

A cleaner's fragrance choice is not a passing thing either. It goes on every surface, in every room, and it is still in the air hours after the vacuum has gone back in the car. The person most affected by that decision is frequently not the person who made the booking. That asymmetry is why my standard is a rule rather than a preference, and it is why allergy-friendly cleaning means no essential oils, not just no synthetic parfum.

What does the work when the fragrance is gone

Take out the scent and something has to replace it. In our case that is professional HEPA vacuums, the correct brush for each surface, steel wool where a surface can take it, citric acid for mineral build-up and soap scum, and physical effort. Mechanical removal, essentially. Soap scum on shower glass responds to a mild acid and sustained scrubbing far better than to anything you can spray and walk away from.

That approach needs time, which is why we charge $85 per hour and price the hours honestly rather than quoting a flat rate for a job we have not seen. A clean priced on speed has to make the minutes back somewhere, and harsh chemistry is usually where it comes from. Strong product compensates for time nobody paid for.

The other thing that changes is what a finished room smells like. Nothing. A properly cleaned bathroom has no smell at all, which unsettles people at first because we have been trained to read scent as evidence. It is not evidence. It is an additive.

Safety notes, because oils turn up in DIY recipes

A few other practical points. Oils oxidise as they age, and oxidised citrus oils in particular are more irritating than fresh ones, so an old bottle is not a safer bottle. They can damage some plastics and finished timber. And a homemade spray with oil floating on top is not a diluted product, it is an undiluted product waiting for whoever gets the last spray.

If you want to keep using them

Plenty of people use essential oils without any trouble, and I have no interest in telling someone their house is wrong. If they stay, use them deliberately.

• Keep them out of bedrooms, where exposure runs for 8 hours at a stretch with the door shut.
• Ventilate afterwards. Open a window rather than closing the room to hold the scent in.
• Do not use them on floors, benchtops or anywhere a pet or a crawling child has sustained skin contact.
• If there is a cat in the house, check with your vet before using them anywhere at all, and never on the animal.
• Stop entirely if someone in the house has said they react. Their reaction outranks anybody else's preference for the smell.
• Do not rely on them to disinfect. That is a separate job with separate requirements.

My position is narrower than most of the natural cleaning industry, and I know it. It comes from the same place as everything else in my product standard. I would rather leave a house with less added to the air than when I arrived, and a scent that 9 people enjoy is still a scent the 10th has to live in.