VOCs: the invisible pollutants in the air of our homes

We spend the vast majority of our time indoors: home, office, transport, shops. According to the French indoor air quality observatory (OQAI), a French person spends on average close to 85 % of their time in enclosed spaces. That, far more than outside, is where the quality of the air we breathe is decided. And that is where a family of pollutants we hear too little about concentrates: volatile organic compounds, or VOCs.

What is a VOC?

Volatile organic compounds are chemical substances that evaporate easily at room temperature and spread through the air. They are found in a multitude of everyday products: paints, glues, new furniture, scented candles, air fresheners, and a large share of cleaning products. Formaldehyde, synthetic limonene, and certain solvents or preservatives are among them.

The problem is not their presence as such, but their build-up in a closed volume. Outdoors, these substances disperse. In a kitchen or a bathroom with the doors shut, they accumulate. That is why the US Environmental Protection Agency points out that concentrations of certain pollutants can be two to five times higher indoors than outdoors, and considerably higher still just after using products that emit them.

The role of cleaning products

When you spray a cleaner, you are not only depositing a liquid on a surface: you are projecting into the air, as a fine aerosol, part of the solvents and fragrances it contains. Those microdroplets stay suspended, are inhaled, and keep evaporating after the surface has dried.

ANSES, the French health and safety agency, has repeatedly documented the contribution of cleaning products and air fresheners to indoor air pollution. Sprays in particular are singled out: their delivery method maximises how much of the substance ends up airborne. Some studies associate regular, heavy exposure to these emissions with irritation of the airways, especially in poorly ventilated homes or among sensitive individuals.

This is not a call for panic. Occasional use in a ventilated room bears no comparison with occupational exposure. But the build-up, product after product, day after day, in homes made ever more airtight for energy reasons, deserves to be taken seriously.

Airtightness: the paradox

This is a perverse effect rarely mentioned. To cut heat loss, our homes are better and better insulated and ever more airtight. Excellent for the heating bill and for the climate. But that airtightness also traps indoor pollutants, which are renewed less naturally. Without effective ventilation, a home that performs well on energy can concentrate more VOCs than an old draughty one.

Hence two complementary levers: ventilate, and reduce the sources of emission.

Reducing at source

Airing remains the first move, free and effective: ADEME and OQAI recommend opening the windows at least ten minutes a day, and systematically during and after cleaning. But airing only removes what has already been emitted. The more robust approach is to emit less.

That comes down to the choice of products. A restrained formulation, without superfluous solvents, with fragrances of natural origin rather than heavily loaded synthetic ones, mechanically reduces the quantity of VOCs projected into the air. Demanding environmental standards, such as Ecocert's Ecodetergent or the EU Ecolabel, govern precisely those ingredients and restrict the most problematic substances.

Format matters too. A tablet dissolved in water and then applied with a conventional trigger bottle projects the solution without propellants and without the solvent load of a pressurised aerosol. The gesture stays the same for you; the footprint on the air in your kitchen is lighter.

What to remember

The air in our homes is an underestimated health issue, precisely because it is invisible. Cleaning products are one of its controllable sources. We will not do away with them: cleaning remains essential. But we can choose restrained, certified formulas, prefer natural fragrances, ventilate while cleaning, and favour gestures that do not needlessly aerosolise solvents. Breathing healthier air at home does not require giving up cleanliness. It starts with looking more closely at what we spray.

Sources

• OQAI (French indoor air quality observatory): time spent in enclosed spaces and levels of indoor pollution. oqai.fr
• US EPA (Environmental Protection Agency), *Introduction to Indoor Air Quality* and *Volatile Organic Compounds' Impact on Indoor Air Quality*: indoor concentrations often 2 to 5 times higher than outdoors. epa.gov
• ANSES (French agency for food, environmental and occupational health and safety), work and opinions on indoor air quality, cleaning products and air fresheners. anses.fr
• ADEME, guide *Un air sain chez soi*: recommendations on ventilation and on reducing sources. agirpourlatransition.ademe.fr
• Ecocert Greenlife, *Ecodetergent* standard; European Commission, *EU Ecolabel*: rules on substances and fragrances. detergents.ecocert.com and environment.ec.europa.eu/ecolabel

The thresholds and percentages cited refer to the publications of the bodies mentioned and should be confirmed against the primary sources before distribution.