Harmful Indoor Air Pollutants You Should Worry About

Harmful Indoor Air Pollutants You Should Worry About

It’s easy to get a little paranoid when it comes to the chemicals, microorganisms, and pollutants floating around our indoor spaces. Is there carbon monoxide in the air? Offgassing from drywall or particle board? And what about biological contaminants, pesticides, and volatile organic compounds (VOCs)?

While we don’t want to overreact, there is definitely cause for concern. The Environmental Protection Agency (EPA) has stated that indoor air is often two to five times as polluted as outdoor air.

Your home is a breeding ground for all kinds of bacteria, dust, animal dander, mold and a whole host of other contaminants. Between your pets, poor ventilation, new furniture or upholstery, and household cleaning products, the inside of your home has been taken siege by harmful pollutants.

This is due in part to many household cleaners and materials that contain volatile organic compounds (VOCs) and other toxins. Additionally, the more energy-efficient and airtight our homes, offices, schools, and apartments get, the less fresh air gets in to replace the potentially harmful substances inside.

The home is where you and your family spend most of your time. Make sure it isn’t making you sick.

Common Indoor Air Pollutants

Here is a list of the most common indoor air pollutants:

  • asbestos
  • bacteria
  • carbon dioxide
  • carbon monoxide
  • dander
  • dust
  • dust mites
  • fungi
  • insects and cockroaches
  • lead
  • mold
  • pesticides
  • pollens
  • radon
  • rats, mice, and other pests
  • viruses

To make things easier, we’re splitting these contaminants into three categories: biological pollutants, carbon monoxide, and volatile organic compounds.

Biological Pollutants

As the name implies, biological pollutants come from living organisms. They are often found in areas with sources of food and water.

Common biological contaminants include:

  • animal dander
  • bacteria
  • dust and dust mites
  • molds and mildew
  • pests
  • cockroaches
  • pollen
  • viruses


Biological pollutants can come from a variety of sources, including people and animals, pollens (plants), mold, viruses, and bacteria. Mold, mildew, pests, and other biological contaminants are often found in central heating and cooling systems, which then get distributed throughout the home.

Other common places where biological contaminants thrive are unvented bathrooms and kitchens, around windows, laundry rooms, attics, and other damp and dirty areas in the home. Bedding, carpet, and other places where dust gathers can also support biologicals. The contaminants are so small that they can be inhaled without knowledge.

Health effects and symptoms of biological contaminants include:

  • allergic rhinitis
  • allergies and asthma
  • coughing and sneezing
  • dizziness and shortness of breath
  • fever
  • hypersensitivity pneumonitis
  • influenza, measles, and chicken pox
  • lethargy and nausea
  • respiratory and digestive problems
  • itchy and watery eyes

The young and elderly are particularly susceptible to biological agents and other indoor air pollutants.

Here are some of the best ways you can reduce exposure to biological pollutants inside your home:

  • Clean your home frequently, especially if you notice any mold or mildew. You can drastically reduce exposure to dust mites, pollens, dander, and other pollutants through regular cleaning.
  • Get rid of any excess moisture and fix water leaks as soon as possible.
  • Maintain a relative indoor humidity of between 30% and 60%. Control humidity with working dehumidifiers, ventilation, and exhaust fans.
  • Clean humidifiers according to manufacturer instructions.
  • Use integrated pest management techniques to reduce the need for pesticides.
  • Make sure you have working exhaust fans for kitchens, bathrooms, and clothes dryers.
  • Properly ventilate the attic, basement, and crawl spaces.
  • If there’s any water damage, clean and dry the items completely within 24 hours. If they are not salvageable, take them outside to the trash.
  • Consider making waterproofing improvements to the attic and basement. Fix any leaks and seepage. Consider a sump pump to prevent basement flooding.
  • Frequently clean and disinfect the basement drain.

For more information on biological pollutants in your home, refer to this brochure by the American Lung Association and U.S. Consumer Product Safety Commission.

Carbon Monoxide (CO)

Carbon monoxide is the most dangerous indoor pollutant. According to the Centers for Disease Control and Prevention (CDC), CO poisoning kills at least 430 people in the U.S. every year! An additional 50,000 Americans are hospitalized due to accidental CO exposure. Since you can’t see, smell, or taste it, CO can kill without warning.

Carbon monoxide is produced by any fuel-burning process, including:

  • kerosene and gas space heaters
  • fireplaces and wood stoves
  • furnaces and boilers
  • water heaters
  • gas stoves
  • generators and other gas-powered equipment
  • automobile exhaust
  • tobacco smoke

Without proper ventilation, any of the above can create unsafe levels of carbon monoxide inside the home. CO levels can build up to unsafe levels in enclosed or partially enclosed spaces.

There are some symptoms that might tip you off, but in order to detect CO, you need a carbon monoxide detector.

Some of the health effects associated with carbon monoxide exposure include:

  • fatigue
  • chest pain
  • impaired vision
  • reduced brain function
  • impaired vision and coordination
  • cold and flu-like symptoms
  • headaches
  • dizziness and confusion
  • nausea
  • death (at high concentrations and long exposure)

Carbon monoxide is so dangerous because it inhibits oxygen intake by forming carboxyhemoglobin in the blood. It’s important to be aware of this very dangerous indoor air pollutant. Luckily, it’s pretty easy to prevent and detect dangerous levels of carbon monoxide in the home.

Protect you and your family from carbon monoxide by following these prevention tips:

  • Install working CO detectors on every level of the home and outside each sleeping area. For the best protection, install inter-connected alarms so that when one goes off, they all go off.
  • Change the batteries in existing CO and smoke detectors at least once a year. Replace all smoke and CO alarms every 10 years or according to the manufacturer’s instructions.
  • Have a professional inspect your fuel-burning appliances (oil and gas heaters, furnaces, boilers, water heaters, fireplaces, and wood stoves) once a year before the heating season begins.
  • Change or clean your air filter every 30-90 days to increase airflow and help prevent blockages that may increase your risk of CO poisoning. A clean air filter improves overall indoor air quality and energy efficiency.
  • Make sure fireplaces, chimneys, vents, and flues are properly sealed and unblocked.
  • Periodically inspect ventilation lines to make sure they aren’t blocked by debris.
  • Although it may be tempting, never run a motor vehicle, generator, or any gas-powered engine indoors or within 20 feet of any open windows, doors, or vents.
  • Do not use grills, lanterns, or portable camping stoves inside a home, tent, or vehicle.

If you suspect carbon monoxide poisoning, go outside and call 911 or a health care professional right away. For more information on carbon monoxide poisoning, visit the CDC’s Carbon Monoxide Poisoning page.

Volatile Organic Compounds


Volatile organic compounds are carbon-based chemicals that get emitted from a variety of common household products. If used over time or in poorly ventilated spaces, these VOC toxins can create many problems for your health and the environment.

Sources of VOCs include:

  • aerosol sprays and air fresheners
  • building materials and furnishings
  • cleaners and disinfectants
  • cosmetics
  • fuels and automotive products
  • glues, adhesives, degreasers, and hobby supplies
  • paints, paint strippers, and solvents
  • pesticides
  • varnishes, wax, and wood preservatives

While not all of these products will release organic compounds when you use them, most will, and some even release VOCs when they are stored. That’s why it’s important to read the labels on the products you buy and follow the instructions carefully. Many times, they will tell you to use the products outdoors or in a well-ventilated space.

In an EPA study completed in 1985, many common organic pollutants were found to be two to five times higher inside homes than outside.

Signs and symptoms of VOC exposure include:

  • allergic reactions
  • damage to liver, kidney, and central nervous system
  • dizziness, fatigue, and nausea
  • dyspnea
  • emesis
  • epistaxis
  • eye, nose, and throat discomfort
  • headaches

Some VOCs are even known or suspected to cause cancer. Similar to other sources of indoor air pollution, the effects depend on the level and length of exposure.

Luckily, there are many ways you can prevent exposure to volatile organic compounds:

  • Improve ventilation levels.
  • Follow label instructions carefully.
  • Look for products with no or low VOCs.
  • Reduce need for pesticides by using integrated pest management techniques.
  • Open windows when using VOC products.
  • Buy small quantities that you know you will use soon.
  • Throw away old and unused chemicals safely.
  • Keep VOC products out of reach of pets and children.
  • Switch to natural cleaners and household products.
  • Consider making your own cleaners using natural ingredients.

To learn more about volatile organic compounds, visit ASHRAE’s Indoor Air Quality Guide.

Other Pollutants and Sources of Indoor Air Pollution

Volatile organic compounds, biological contaminants, and carbon monoxide are the most common sources of indoor air pollution, but there are other pollutants to be aware of.

Learn how to reduce your exposure to the following indoor pollution sources:

Protect Indoor Air Quality in Your Home

Your home should be a place where you can find comfort. That’s why it is so important that you tackle poor indoor air quality as soon as possible. If your home has poor air quality, you and your loved ones may be experiencing a myriad of side effects, such as allergies, headaches, fatigue, and cold-like symptoms.

The heating, ventilation, and air conditioning system is a major gathering place for contaminants, and cleaning it will take a major source of air pollution away. Make sure you are scheduling professional furnace maintenance every fall and air conditioning maintenance every spring.

Once you’ve had the system cleaned and tuned up, ask your HVAC specialist about options for various filters, air purifiers, and ventilation improvements. A Bell Brothers technician will be able to pinpoint the specific problem and recommend solutions to combat it.

Air Purifiers

A great way to combat poor indoor air quality is through purchasing an air purifier your home. There are various types of purifiers on the market, all working to provide you with safe, clean air. Once your purchase an air purifier, you’ll soon discover the many benefits they provide.

Air purifiers are a great weapon to use as their primary function is to trap all the harmful particulate matter that could otherwise make you or your loved ones ill.

Here are some benefits an air purifier will provide for you and your home:

  • reduce allergy and asthma triggers
  • eliminate pet dander, dust, and odor
  • trap tobacco smoke
  • extract airborne asbestos particles
  • eliminate radon gases
  • remove fumes and pollutants that come from outside
  • reduce carbon dioxide levels
  • reduce volatile organic compounds
  • remove insects, such as disease-carrying mosquitoes
  • lessen contamination and infection
  • protect against respiratory illnesses
  • produce clean air for better health, mood, and productivity
  • increase air circulation to trap more pollutants

Not all air purifiers are equal. For the most suitable air purifier, speak with a professional HVAC technician.

The first step in achieving better indoor air quality in Sacramento, CA is to schedule an appointment with a qualified HVAC technician.

Contact Bell Brothers if you have any questions about the indoor air quality in your home. Often, an HVAC professional will be able to fix the problem by improving ventilation, humidity levels, and making sure your central heating and cooling system is properly inspected, cleaned, and tuned up.