When we think about air pollution, we often picture highways or smokestacks. But the most harmful air is often much closer, it's in our homes. In fact, indoor air can be up to 5 times more polluted than outdoor air. And the very things we bring inside to make our lives better: new furniture, fresh paint, cleaning supplies, can quietly release harmful pollutants into the air we breathe.
This guide breaks down six common indoor air pollutants, where they come from, and how they impact your health. We also share how you can take simple steps to fight back.
What Are Pollutants?
Pollutants are substances that contaminate the environment and can cause harm to human health, ecosystems, or materials. The EPA defines six common air pollutants (also called "criteria pollutants") as nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone, lead, and particulate matter. These are mainly found outdoors—but they also seep into our homes. On top of that, many additional pollutants originate inside our living spaces, too.
Pollutants are classified in a few different ways:
- Quantitative pollutants occur naturally but become dangerous at high concentrations (like carbon dioxide).
- Qualitative pollutants are synthetic or man-made (like insecticides or formaldehyde).
- Primary pollutants are released directly into the air.
- Secondary pollutants are formed by chemical reactions (and are often even more harmful).
The 6 Most Common Indoor Air Pollutants
1. Volatile Organic Compounds (VOCs)
Examples of pollutants: Formaldehyde, Benzene, Toluene, XyleneSources of indoor air pollutants: Paint, furniture, cleaning supplies, air fresheners
VOCs are harmful gases released by many of the products we bring into our homes. They're often colorless and odorless, yet linked to symptoms like headaches, fatigue, brain fog, itchy eyes, and even long-term risks like organ damage and cancer.
The most common way VOCs enter your home? Everyday choices. We paint nurseries, buy new furniture, light candles, or do a home remodel, all with the best intentions. But these decisions often introduce chemicals like formaldehyde, benzene, toluene, and xylene into the air we breathe.
Indoor VOC concentrations are usually 2 to 5 times higher than outdoor levels, and because we spend 90% of our time indoors, these pollutants build up quickly.
2. Off-Gassing from Home Furnishings
Examples of pollutants: VOCs like formaldehyde, toluene, and moreSources: New furniture, carpets, mattresses, cabinetry, laminates
Yes, we’re talking about VOCs again, but this one’s worth its own callout. Off-gassing from new furniture and home goods is one of the most concentrated and prolonged sources of VOCs in your space.
Even so-called “low-VOC” products can release gases for months. That “new furniture smell”? Often a sign of chemicals like formaldehyde lingering in the air.
Many people experience this during joyful moments like prepping a nursery or refreshing a room. You might bring home a crib, a new couch, or a mattress, and unknowingly introduce pollutants that stick around far longer than expected.
3. Indoor Particulate Matter (PM)
Examples of pollutants: Dust, soot, pet dander, smoke, pollenSources: Cooking, candles, fireplaces, HVAC systems, outdoor air
Particulate matter refers to microscopic solids and liquids suspended in the air. Because PM is so small, it can enter your lungs and bloodstream, contributing to respiratory problems and cardiovascular disease.
4. Biological Pollutants
Examples of pollutants: Mold spores, pet dander, pollen, bacteria, virusesSources: Humid areas, dirty filters, damp basements, poorly ventilated bathrooms
These living organisms can trigger allergies, asthma, and other respiratory issues. Mold and bacteria especially thrive in high humidity and can grow out of control without proper air circulation or dehumidification.
5. Carbon Monoxide (CO)
Examples of pollutants: Carbon monoxide gas (CO)Sources: Gas stoves, water heaters, fireplaces, space heaters
Colorless and odorless, CO is one of the most dangerous indoor air pollutants. It forms when fuels like gas or wood aren’t burned completely. Even at low levels, it can cause dizziness, confusion, or nausea. At high levels, it can be life-threatening.
6. Lead
Examples of pollutants: Lead dust, flakes from old paintSources: Lead-based paint (especially in homes built before 1978), contaminated soil, some ceramics
Though mostly phased out, lead still lingers in many older buildings. When lead paint is disturbed, it can release dust or chips that contaminate indoor air. Exposure can cause developmental issues, especially in children.
So, What Can You Do?
1. Open Your Windows (But Know the Limits)
Ventilation helps reduce indoor air pollutants, but it's not a cure-all. Pollution from outdoor sources can still enter, and VOC levels often rise again shortly after windows are closed.
2. Control Humidity
Use a dehumidifier in damp areas, fix leaks quickly, and make sure your home is well ventilated to prevent mold and bacteria from spreading.
3. Choose Safer Products
Look for non-toxic, fragrance-free, or third-party certified cleaning and household products. Be skeptical of vague terms like "natural" or "green."
4. Be Smart About Furniture
Buy second-hand when possible (used items have already off-gassed) or look for certifications like Greenguard to minimize VOC exposure.
5. Use a True Air Purifier
Traditional purifiers with HEPA filters can help reduce particulate matter, but most can’t remove VOCs. If you want to tackle the most harmful indoor air pollutants, you'll need a solution designed for that.
A Natural System That Actually Works
At Neoplants, we‘re working with nature to create solutions that will help us all breathe better. Our bioengineered plant system was specifically developed to fight against the four most common and harmful VOCs: formaldehyde, benzene, toluene, and xylene. It uses a proprietary microbiome that lives on the soil’s surface and is 30x more effective than regular houseplants at cleaning the air.
Whether you:
- Use Power Drops monthly to supercharge the houseplants you already own and provide continuous VOC protection
- Or bring home Neo Px, our complete clean-air system with a plant, custom-designed planter, and a three-month starter supply of Power Drops
each setup is effective for a space of about 160 square feet, think bedroom, home office, or nursery. Just remember to reapply Power Drops monthly to keep performance strong.
You’re not just decorating your home, you’re protecting it.
TL;DR: Why This Matters
- Indoor air can be more polluted than outdoor air
- Common activities like painting, cleaning, or buying new furniture introduce harmful VOCs
- Exposure to indoor air pollutants can lead to headaches, fatigue, poor sleep, and long-term illness
- Most traditional purifiers don’t eliminate VOCs
Neoplants offers a proven, natural system that helps you breathe easier
Sources:
Summary of the Clean Air Act | US EPAOpens in a new tab.
Biological Pollutants' Impact on Indoor Air Quality | US EPAOpens in a new tab.
Lead & Health | California Air Resources BoardOpens in a new tab.
Carbon Monoxide (CO) Poisoning in Your Home | Minnesota Department of HealthOpens in a new tab.
Indoor Particulate Matter | U.S. EPA Opens in a new tab.
Toxic VOCs and Confined Space Entry | Occupational Health & Safety Opens in a new tab.
Scented Products Emit a Bouquet of VOCs | PMCOpens in a new tab.
Air Pollution and Cardiovascular Disease Basics | US EPA Opens in a new tab.
NASA Clean Air Study | NASAOpens in a new tab.
What are volatile organic compounds (VOCs)? | US EPAOpens in a new tab.