What Are VOCs in Cleaning Products, and Should You Worry?

What is a VOC, in plain terms?

A volatile organic compound is a carbon-based chemical that evaporates readily at room temperature. That is the whole definition. It is not a synonym for “toxic”, and it is not a synonym for “synthetic”: ethanol is a VOC, so is the limonene in an orange peel, and so are many of the compounds in a bottle of lemon-scented cleaner. What matters is which compounds, at what concentration, in what size of room, with what ventilation.

The reason cleaning products come up so often in VOC conversations is that they are applied indoors, in the breathing zone, in a space with limited air exchange. Outdoors, the same emission disappears into a very large volume of air. In a closed bathroom it does not.

The baseline number worth carrying around comes from EPA’s Total Exposure Assessment Methodology work, which found roughly a dozen common organic pollutants at levels 2 to 5 times higher inside homes than outside, regardless of whether the homes were rural or industrial. Concentrations of many VOCs run consistently higher indoors, up to ten times higher, and during and for several hours after activities such as paint stripping, levels can reach a thousand times outdoor background. There are no federally enforceable VOC standards for non-industrial indoor settings in the United States, and Canada likewise has guidance rather than enforceable residential limits.

The scale is bigger than most people expect at city level too. McDonald and colleagues (2018), writing in Science, found that volatile chemical products, a category that includes cleaning agents and personal-care products alongside coatings, inks and adhesives, now account for roughly half of fossil-fuel VOC emissions in industrialised cities, because vehicle emissions have fallen so far. For particle-forming emissions specifically, chemical products contribute about twice as much as transportation.

Do green cleaning products emit fewer VOCs, or none?

Fewer. Not none. This is the finding we think makes or breaks the credibility of anyone writing about natural cleaning, so here it is in full.

A 2023 study in Chemosphere by Temkin and colleagues used chamber testing on 30 cleaning products and detected 530 unique VOCs, of which 193 were classified as hazardous for effects including respiratory damage, cancer risk and developmental or reproductive harm.

Two disclosures belong with that result. First, the study was conducted by EWG researchers, and EWG is an advocacy organisation, not a neutral standards body. We are citing a study that supports our own commercial position, authored by people whose position it also supports, and you should weigh it accordingly. Second, the American Cleaning Institute, the industry association, issued a statement disputing it.

There is also genuine scientific disagreement about the direction. Earlier headspace studies by Anne Steinemann found essentially no difference between green and conventional products in the number of VOCs and hazardous VOCs emitted. The 2023 work used chamber testing and measured concentration and emission factor rather than mere presence, which is a better method for answering “how much”, but the honest summary of the literature is that green products emit less by concentration and are not a different kind of thing.

The practical reading: the category label on the bottle is a weak signal, and fragrance-free is a much stronger one.

Why is fragrance the biggest lever?

Because fragrance is both the largest VOC load in most cleaning products and the part of the label that is legally allowed to stay hidden. A single “fragrance” or “parfum” entry can stand in for dozens of individual chemicals, and Canadian cleaning products are not required to list full ingredients at all.

Health Canada is unusually direct about this in its Healthy Home Guide: “Minimize the use of scented products, such as plug-in or aerosol deodorizers (air fresheners). These products can hide odours by producing VOCs. VOCs can cause breathing problems, headaches, and irritation to the eyes, nose and throat.” That is a federal document telling Canadians to use fewer scented products, and it is the strongest single citation on this site for going fragrance-free.

There is also a chemistry problem specific to “natural” scents. Citrus and pine fragrances, and many essential oils, contain d-limonene and related terpenes. Terpenes react with indoor ozone to produce formaldehyde, hydrogen peroxide and secondary organic aerosol, which is to say ultrafine particles. This has been documented in chamber work even at low ozone concentrations, measured in the range of 17.2 to 21.4 parts per billion. We are not claiming a citrus cleaner is manufacturing formaldehyde in your kitchen. We are saying the reaction is real and it is a reason “naturally scented” is a weaker position than “unscented”.

And a meaningful share of people notice. Steinemann’s cross-national survey work found 32.2% of adults report adverse health effects from fragranced consumer products, 15.7% report health problems from being in a room cleaned with scented products, and 57.8% of people with asthma report adverse effects. These are self-reported symptoms from population surveys rather than clinical diagnoses, and they come from a single research group, so read them as “report” rather than as prevalence. Even discounted, a number that size is a good reason not to scent someone else’s home without asking.

Should you actually worry?

Worry is the wrong frame. The useful question is which changes buy the most reduction for the least effort, and the answer is better than the anxiety suggests.

• Go fragrance-free first. It is the single change with the clearest evidence behind it, from the chamber study, from the terpene chemistry, and from Health Canada’s own advice.
• Spray the cloth, not the air. Zock and colleagues (2007) followed 3,503 people who were asthma-free at baseline and found weekly cleaning-spray use associated with asthma symptoms at a relative risk of 1.49 (95% CI 1.12 to 1.99), and use on four or more days a week associated with physician-diagnosed asthma at 2.11 (95% CI 1.15 to 3.89). The risk concentrated in glass, furniture and air-freshening sprays, which are precisely the aerosol formats. Wetting a cloth removes most of the breathing-zone exposure at no cost.
• Ventilate while you clean and for a while after. VOC concentration is a function of emission rate and air exchange, and you only control one of those with your product choice.
• Drop the air fresheners. They add VOCs to mask an odour rather than removing its source.
• Use fewer products, in smaller amounts. Dose is real. Most people over-apply.

Where do VOCs matter most?

Sealed workplaces, and the reason is simple: nobody there chose the products. A home occupant can open a window, switch brands, or leave. Staff in an office, a clinic or a salon breathe whatever the cleaning contractor brings in, on a schedule they did not set, in a building with mechanical ventilation they cannot adjust.

That is why the Green Seal GS-37 standard, which is the institutional and janitorial one, caps VOC content and counts every fragrance component present at 0.01% or more toward that cap, and prohibits formulating with asthmagens outright. If you are specifying cleaning for a workplace, that criterion is the one worth writing into the scope of work.

We go through which ingredients are worth avoiding and how Canadian labels handle them in the Canadian label guide, and the certification question in are green cleaning products really safer.

If you are responsible for a workplace and would rather the people in it were not making this calculation on your behalf, our office and small workplace cleaning runs fragrance-free by default, with the low-VOC product list and safety data sheets available to your staff, not just to whoever signs the contract.