The indoor air you breathe.

Our homes are supposed to be sanctuaries, places of comfort and safety. But what if the air we breathe within them isn’t as pure as we think? The truth is, a surprising number of chemical compounds and particles can make their way into our indoor air, potentially impacting our health. Let’s delve into some of the most common culprits found in typical homes.

Volatile organic compounds (VOCs).

Ever notice that “new furniture smell”? Those are VOCs emanating from paints, adhesives, and manufactured wood products like cabinets, flooring, and furniture. Formaldehyde, a specific VOC, is a major concern. These compounds have levels that are higher in:

• Homes with smokers. Tobacco smoke contains formaldehyde. If someone in your home smokes tobacco products, the smoke may be the greatest source of formaldehyde in your home.
• Homes with new products or new construction. Formaldehyde levels are higher in newly manufactured wood products such as flooring and furniture. Formaldehyde can also be found in some fabrics.
• Homes built after 1990. Newer homes are better insulated, so less air is moving into and out of the home. Less air movement can cause formaldehyde to stay in the home’s air longer.
• Some manufactured wood products such as cabinets, furniture, plywood, particleboard, and laminate flooring.
• Permanent press fabrics like those used for curtains and drapes or on furniture.
• Household products such as glues, paints, caulks, pesticides, cosmetics, and detergents.
• Gas stoves and open fireplaces can also contain formaldehyde.

Formaldehyde frenzy.

Formaldehyde deserves special mention because of its potential health effects. It can irritate eyes, nose, and throat, and long-term exposure is linked to some respiratory problems. People with respiratory problems such as asthma, young children, the elderly, and people with heightened sensitivity to chemicals may be more susceptible to irritation and illness from VOCs.

Studies of workers exposed to high levels of formaldehyde, such as industrial workers and embalmers, have found that formaldehyde causes myeloid leukemia and rare cancers, including cancers of the paranasal sinuses, nasal cavity, and nasopharynx.

The tiny troublemakers: small airborne particles.

These microscopic particles, often referred to as PM2.5, can come from various sources. Dust, animal dander, wildfire smoke, and outdoor air pollution can all contribute. While some particles are relatively harmless, others can irritate lungs and worsen respiratory conditions.

Biological contaminants.

Airborne biological contaminants can cause allergic reactions for a significant portion of the population.

• Molds and mildew: These fungi thrive in damp environments and release spores that can cause allergies and respiratory issues.
• Pollen: Outdoor allergens, like pollen from trees, grasses, and weeds, can enter homes through open windows and doors.
• Bacteria: Bacteria, including those that cause tuberculosis and staphylococcus infections, can be transmitted through the air.
• Airborne viruses are a significant health concern, capable of spreading rapidly and causing widespread illness. These microscopic pathogens are transmitted through respiratory droplets expelled into the air when an infected person coughs, sneezes, or talks.

Examples of viral infections

• Influenza (Flu): This seasonal virus infects millions each year, leading to respiratory illnesses and, in severe cases, hospitalization or death.
• COVID-19: The SARS-CoV-2 virus has had a global impact, leading to widespread illness and economic disruption.
• Measles: Highly contagious, measles can cause serious complications, especially in children.
• Chickenpox: A common childhood illness that can lead to uncomfortable symptoms and secondary infections.
• Respiratory Syncytial Virus (RSV): Particularly harmful to infants and the elderly, RSV can cause severe respiratory infections.
• Avian influenza: While primarily affecting birds, certain strains can transmit to humans, causing serious illness.

Examples of bacterial infections

• Tuberculosis (TB): Caused by Mycobacterium tuberculosis bacteria. People with active TB disease in the lungs or throat can release the bacteria into the air when coughing, speaking, or singing.
• Legionnaires’ disease: A type of pneumonia caused by Legionella bacteria. Infection commonly follows inhalation of contaminated water mist; it generally does not spread from person to person.

Ammonia: household-product exposure.

Ammonia is a colorless gas with a strong odor and is used in some household and window-cleaning products. Using these products can increase indoor exposure. At high concentrations, ammonia can irritate the eyes, throat, and lungs. Adequate ventilation is important when using ammonia-containing cleaners.

Combustion byproducts: hidden dangers.

Combustion byproducts, often overlooked, can pose significant health risks. These harmful substances are released into the air when fuels like natural gas, propane, or kerosene are burned.

Common combustion byproducts

• Carbon monoxide (CO): A colorless, odorless gas, CO can be deadly if inhaled in high concentrations. It reduces the blood’s ability to carry oxygen, leading to symptoms like headaches, dizziness, and nausea.
• Nitrogen dioxide (NO2): A reddish-brown gas, NO2 is a major component of smog and can irritate the respiratory system. Long-term exposure can lead to chronic respiratory problems.
• Particulate matter: Tiny particles, including soot and dust, can penetrate deep into the lungs and cause respiratory issues.

Other notable byproducts

• Nitrogen oxide: A byproduct of natural gas combustion, nitrogen oxide contributes to air pollution and can aggravate respiratory conditions.
• Acid aerosols: Produced by kerosene combustion, acid aerosols can irritate the eyes, nose, and throat.

Radon: a naturally occurring radioactive gas.

Radon forms through the natural radioactive decay of elements in soil, rock, and groundwater. This gas can enter homes through cracks and other openings and accumulate indoors. Breathing radon increases lung cancer risk.

Surface microorganisms.

Surface microorganisms are tiny organisms that can live on various surfaces, including countertops, doorknobs, and electronic devices. While many are harmless, some can cause illness if they come into contact with our bodies.

• SARS-CoV-2: The virus responsible for COVID-19 can survive on surfaces for varying periods.
• Staphylococcus aureus: A type of bacteria commonly found on the skin and in the nose that can cause skin infections.
• MRSA: A drug-resistant strain of Staphylococcus aureus, MRSA can lead to serious infections.
• Escherichia coli (E. coli): Certain strains of E. coli can cause foodborne illness.

Airborne virus inactivation and surface disinfection are separate outcomes. A 2023 laboratory study using a GPS-FC48-AC ionizer reported reduced infectivity of airborne influenza A and B, RSV, and SARS-CoV-2 under the tested conditions. It did not test AEIRO TBPI® equipment or surface disinfection. These results therefore do not establish airborne-virus or surface-disinfection performance for AEIRO products. Any AEIRO claim needs supporting test results for the specific model, organism, exposure time, and measured outcome.

Reducing indoor PM: a three-pronged approach.

• Source control: Minimizing the sources of PM within the building.
• Ventilation: Diluting indoor air pollutants by bringing in fresh air.
• Air cleaning: Actively removing PM from the air.

While source control and ventilation are important first steps, optimal indoor air quality requires the addition of air cleaning technologies. These technologies can enlarge particles, making it easier for HVAC systems to filter them out.

How soft ionization fights particulate matter.

• Installation: Soft ionization devices are installed within your HVAC system’s ductwork.
• Ion generation: As your HVAC system circulates air, it passes over the ionizer, which generates positive and negative ions. These ions are then distributed throughout your indoor space.
• Particle clustering: The ions attach to airborne particles, causing them to clump together and form larger clusters.
• Improved filtration: These larger clusters are more easily captured by your HVAC system’s air filter. Soft ionization also helps clump together many medium-sized particles floating in the air, further reducing the overall particle count.

Sources.

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2. U.S. Environmental Protection Agency. Air Cleaners, HVAC Filters, and Respiratory Viruses. Evidence requirements and limits of bipolar-ionization research. https://www.epa.gov/indoor-air-quality-iaq/air-cleaners-hvac-filters-and-respiratory-viruses
3. U.S. Environmental Protection Agency. What is Radon? Natural origin and entry into buildings. https://www.epa.gov/radon/what-radon
4. U.S. Environmental Protection Agency. Frequent Questions: Radiation Sources. Radon exposure, natural sources, and lung-cancer risk. https://www.epa.gov/radiation/frequent-questions-radiation-sources
5. Centers for Disease Control and Prevention. Tuberculosis: Causes and How It Spreads. Bacterial cause and transmission of active TB. https://www.cdc.gov/tb/causes/index.html
6. Centers for Disease Control and Prevention. How Legionella Spreads. Bacterial cause and exposure through contaminated water mist. https://www.cdc.gov/legionella/causes/index.html
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