When you think about the air inside your home, what comes to mind? Maybe you picture a freshly cleaned living room, open windows on a nice day, or that fresh, clean smell after tidying up. But here’s the thing: clean looking and clean smelling air doesn’t always mean clean air! Our homes are filled with everyday products, furniture, and materials that can affect the air we breathe. From the cleaning supplies we use to the moisture that builds up in our bathrooms, there are plenty of potential sources of indoor air pollutants hiding in plain sight. And because many of these pollutants can’t be seen or smelled, it’s not always easy to know what’s actually floating around in your home.
So, what should you be looking out for? This week, we’re focusing on what I like to call “the big 3”- three common indoor air pollutants that are worth knowing about: VOCs, mold, and formaldehyde. Let’s take a closer look at where they come from, why they matter, and what you can do to help keep your indoor air healthy.
- VOCs: More Common Than You Might Think
Have you ever cleaned your kitchen, sprayed an air freshener, or painted a room and noticed a strong smell afterward? That smell may be a clue that chemicals have been released into the air. Volatile organic compounds, commonly known as VOCs, are a large group of carbon-containing chemicals that can easily evaporate into the air at room temperature. They come from many products and materials we use every day, which means exposure can happen in places we least expect. Common household sources of VOCs include cleaning supplies, paints, adhesives, solvents, air fresheners, fragrances, personal care products, and certain furniture or building materials. Some VOCs can also be released during cooking, hobbies, and other everyday activities.
Not all VOCs are equally harmful. Their potential effects depend on the specific chemical, its concentration, how long someone is exposed, and individual sensitivity. Depending on the compound and exposure level, some VOCs may contribute to eye, nose, and throat irritation, headaches, dizziness, or other health effects. Certain VOCs are associated with more serious long-term health risks. One of the challenges with VOCs is that you cannot identify them all by smell. A strong odor may indicate that chemicals are being released, but some VOCs have little or no noticeable odor. Likewise, a room that smells fresh is not necessarily free of chemical pollutants.
What can you do? Choose household products carefully, follow label directions, and provide appropriate ventilation when cleaning, painting, or using products that release fumes. Store chemicals safely and avoid using air fresheners simply to cover up persistent odors. When possible, consider products with lower chemical emissions.
Because VOCs come from so many different sources, understanding which compounds may be present can be an important part of evaluating your indoor air quality.
- Mold: A Moisture Problem That Can Affect Your Air
Mold is another indoor air quality concern that many homeowners recognize, but not everyone realizes how it develops or how it can affect the indoor environment. Mold is a type of fungus that grows when moisture and suitable organic materials are available. It can develop on drywall, wood, carpet, insulation, and other materials when they become damp or remain wet for too long. Leaks, flooding, condensation, plumbing problems, and persistently high humidity can all contribute to conditions that support mold growth. Bathrooms, basements, kitchens, crawl spaces, and areas around windows or plumbing can be especially important places to check for moisture problems.
You may notice visible spots or patches of mold, discoloration, or a musty odor. However, mold can also grow in hidden areas, such as behind walls, beneath flooring, around leaking pipes, or inside damp building materials. The absence of visible mold does not always mean there is no moisture-related problem. As mold grows, it can release spores and other particles into the environment. Exposure to mold can cause allergic reactions in some people, including sneezing, a runny nose, red or itchy eyes, and skin irritation. Mold exposure can also worsen asthma symptoms in people who are sensitive to it. The key to managing mold is controlling moisture. Simply cleaning a visible patch without addressing the source of the dampness may allow the problem to return.
What can you do? Repair leaks promptly, dry water-damaged materials quickly, use exhaust fans when showering or cooking, and keep indoor humidity at a reasonable level. The U.S. Environmental Protection Agency generally recommends keeping indoor relative humidity below 60%, ideally between 30% and 50% when practical.
If you discover a significant mold problem or suspect hidden moisture damage, consider having the area evaluated by a qualified professional. Air testing may provide additional information in some situations, but it does not replace investigating moisture sources or addressing visible mold growth.
- Formaldehyde: A Chemical That May Be Inside Your Furniture
Formaldehyde may be the one you think about the least. Yet it can be present in many homes because of the materials used to make everyday household products. Formaldehyde is a colorless, strong-smelling chemical used in the manufacture of various resins, adhesives, and other products. One common indoor source is certain pressed-wood products, including particleboard, plywood, and medium-density fiberboard. These materials may be used in cabinets, shelving, flooring, desks, dressers, and other furniture. Formaldehyde can also be associated with some building materials, household products, and other indoor sources. The amount released into the air can vary depending on the product, manufacturing process, age, temperature, and humidity. New furniture, cabinetry, or renovations can sometimes introduce additional formaldehyde emissions into an indoor space. Emissions from certain products may decrease over time, but the rate depends on the material and surrounding conditions.
At elevated concentrations, formaldehyde can irritate the eyes, nose, throat, and respiratory system. Some people may be more sensitive to its effects than others. Formaldehyde is also classified as a human carcinogen, making it important to understand and reduce unnecessary exposure. Like other indoor air pollutants, formaldehyde is not something you can reliably identify by appearance alone. Although it has a recognizable odor at some concentrations, smell is not a dependable way to determine whether levels are safe.
What can you do? When purchasing furniture or building materials, look for products designed to meet applicable low-emission standards. Maintain appropriate ventilation, especially after bringing new products into your home or completing renovations. Managing indoor temperature and humidity can also help limit emissions from some materials. If you’re concerned about formaldehyde in your home, testing can help you better understand whether it is present and at what concentration.
Why These Three Pollutants Matter
VOCs, mold, and formaldehyde have different sources and behave differently in the indoor environment, but they share one important characteristic: you cannot always tell what’s in your air just by looking around. Your home may appear spotless, your furniture may look perfectly normal, and your rooms may smell fresh. Yet everyday materials, household activities, and hidden moisture can still affect indoor air quality. It’s also important to remember that finding a potential source does not automatically mean you have a harmful level of exposure. The type of pollutant, its concentration, the duration of exposure, and the conditions inside your home all matter. The good news is that there are practical steps you can take to support healthier indoor air. Improving ventilation, controlling moisture, choosing household products carefully, and maintaining your home can all make a difference. When questions remain, testing may provide additional information to help guide your next steps.