Volatile organic compounds (VOCs) are a large group of carbon-based chemicals that easily evaporate into the air at room temperature. While VOCs are commonly found in many household products and industrial processes, they play a significant role in air pollution and can have serious health effects, especially in high concentrations. Some VOCs are harmless, while others can cause short- or long-term health problems, including respiratory issues, dizziness, and even cancer. 

This blog focuses on some of the biggest VOC contributors in dirty air, breaking them into categories based on their chemical similarities and common sources. We’ll also touch on the NIOSH (National Institute for Occupational Safety and Health) recommended exposure limits where available and the potential health risks associated with each VOC or category. 

 

         1. Benzene, Toluene, Ethylbenzene, Xylene Isomers (BTEX)

Benzene, toluene, ethylbenzene, and xylene (often referred to as the BTEX group) are commonly found together in industrial emissions, vehicle exhaust, and the production of petroleum products. These compounds are some of the most concerning VOCs due to their widespread use and serious health effects. 

 

        Sources: 

    • Vehicle emissions 
    • Industrial processes (e.g., oil refineries, chemical plants) 
    • Paints, varnishes, adhesives 
    • Cigarette smoke 
    • Gasoline and other fuels 

 

         Health Effects: 

    • Benzene: Long-term exposure to benzene is linked to cancer, particularly leukemia. Short-term exposure can cause dizziness, headaches, drowsiness, and unconsciousness. 
    • Toluene: High concentrations of toluene can cause headaches, dizziness, and nausea. Chronic exposure may lead to liver and kidney damage, as well as developmental effects in fetuses. 
    • Ethylbenzene: Short-term exposure to high levels can cause eye and throat irritation, dizziness, and respiratory issues. Long-term exposure may damage the liver, kidneys, and nervous system. 
    • Xylene: Xylene can cause headaches, dizziness, respiratory irritation, and in higher concentrations, damage to the liver and kidneys. 

 

       NIOSH Recommended Exposure Limits: 

    • Benzene: 0.1 ppm (parts per million) TWA (Time-Weighted Average) for a 10-hour workday 
    • Toluene: 100 ppm TWA 
    • Ethylbenzene: 100 ppm TWA 
    • Xylene: 100 ppm TWA 

 

 

      2. Pentane, 2-Methylbutane, Isobutane

Pentane, 2-methylbutane, and isobutane are hydrocarbons used primarily as solvents, refrigerants, and aerosol propellants. These chemicals are common VOCs that can contribute to indoor air pollution. 

 

     Sources: 

    • Refrigerants and aerosol sprays 
    • Gasoline and natural gas 
    • Chemical manufacturing processes 
    • Foam insulation products 
    • Personal care products such as perfumes or shaving creams 

 

     Health Effects: 

    • Short-term exposure can cause dizziness, headaches, and nausea. 
    • In high concentrations, these chemicals can displace oxygen in the air, leading to suffocation. 
    • Chronic exposure may result in central nervous system depression and memory impairment. 

 

     NIOSH Recommended Exposure Limits: 

    • Pentane: 1000 ppm TWA 
    • Isobutane: 800 ppm TWA 

 

 

     3. Ethanol, Isopropanol

Ethanol and isopropanol (isopropyl alcohol) are alcohols commonly found in household cleaning products, personal care items, and industrial solvents. Both are widely used and can evaporate easily. Although these alcohols are fairly innocuous, it is still best to keep the levels as low as possible.  

 

     Sources: 

    • Disinfectants and hand sanitizers 
    • Cleaning products 
    • Paint thinners 
    • Pharmaceuticals 
    • Personal care products (e.g., perfumes, hairsprays) 

 

     Health Effects: 

    • Inhalation of high concentrations can cause dizziness, headaches, and nausea. 
    • Prolonged exposure can irritate the respiratory system and skin. 

 

     NIOSH Recommended Exposure Limits: 

    • Ethanol: No established NIOSH limit for ethanol. 
    • Isopropanol: 400 ppm TWA 

 

 

      4. Terpenes (e.g., Hexanal, α-Pinene, Limonene)

Terpenes, including compounds like hexanal, α-pinene, and limonene, are naturally occurring VOCs commonly found in plants and trees. They are often used in cleaning products, fragrances, and air fresheners due to their pleasant, citrusy or pine-like scent.  

 

     Sources: 

    • Essential oils 
    • Cleaning products and air fresheners 
    • Candles 
    • Paints and varnishes 
    • Naturally occurring in wood  

 

     Health Effects: 

    • Inhalation of terpenes in high concentrations can cause respiratory irritation, headaches, and dizziness. 
    • In poorly ventilated spaces, terpenes can react with other chemicals in the air to form harmful secondary pollutants like formaldehyde and fine particulate matter. 

 

     NIOSH Recommended Exposure Limits: 

    • No established NIOSH limits for individual terpenes like limonene or α-pinene. 

 

 

     5. Naphthalene, 1,4-Dichlorobenzene

Naphthalene and 1,4-dichlorobenzene are commonly used in mothballs, air fresheners, and some industrial processes. Both chemicals are semi-volatile, meaning they can easily evaporate and contribute to poor indoor air quality. 

 

     Sources: 

    • Mothballs/moth crystals  
    • Air fresheners 
    • Pesticides/herbicides  
    • Arts & crafts supplies 
    • Oil-based paints 
    • Urinal cake deodorizers  

 

     Health Effects: 

    • Naphthalene: Short-term exposure to naphthalene can cause headaches, nausea, and respiratory issues. Long-term exposure is linked to hemolytic anemia (damage to red blood cells) and is classified as a possible human carcinogen. 
    • 1,4-Dichlorobenzene: Exposure can cause dizziness, headaches, and liver damage. Chronic exposure has been linked to a higher risk of liver cancer. 

 

     NIOSH Recommended Exposure Limits: 

    • Naphthalene: 10 ppm TWA 
    • 1,4-Dichlorobenzene: 75 ppm TWA 

 

 

      6. Tetrachloroethene (Perchloroethylene)

Tetrachloroethene, also known as perchloroethylene or PCE, is a common solvent used in dry cleaning and industrial degreasing. It is a persistent pollutant that can remain in the environment for long periods and pose health risks. 

 

     Sources: 

    • Dry cleaning fluids 
    • Metal degreasing solvents 
    • Paint strippers 
    • Glass cleaner  

 

     Health Effects: 

    • Short-term exposure can cause dizziness, headaches, and respiratory irritation. 
    • Long-term exposure is linked to liver and kidney damage, as well as cancer in humans. 

 

     NIOSH Recommended Exposure Limits: 

    • Tetrachloroethene: 25 ppm TWA 

 

 

       7. Acetone

Acetone is a widely used solvent found in paints, varnishes, nail polish removers, and cleaning products. It is one of the less toxic VOCs but can still cause health problems in high concentrations. 

 

     Sources: 

    • Nail polish and nail polish remover 
    • Paints, coatings, and adhesives 
    • Industrial solvents 
    • Cleaning products  
    • Metal polish  

 

     Health Effects: 

    • Short-term exposure to acetone can cause headaches, dizziness, and eye, nose, and throat irritation. 
    • Prolonged exposure can lead to skin irritation and central nervous system depression. 

 

     NIOSH Recommended Exposure Limits: 

    • Acetone: 250 ppm TWA 

 

 

       8. Formaldehyde

Formaldehyde is a potent VOC that is commonly used in building materials, such as pressed wood products, and in various household products. It is also a byproduct of combustion processes like cigarette smoking. 

 

     Sources: 

    • Building materials (e.g., plywood, particleboard) 
    • Household products (e.g., adhesives, cosmetics) 
    • Combustion sources (e.g., cigarettes, stoves) 

 

     Health Effects: 

    • Formaldehyde is a known human carcinogen and can cause cancer with long-term exposure. 
    • Short-term exposure can cause eye, nose, and throat irritation, coughing, and skin irritation. 
    • Prolonged exposure can lead to more serious respiratory issues and allergic reactions. 

 

     NIOSH Recommended Exposure Limits: 

    • Formaldehyde: 0.016 ppm TWA  

 

 

Volatile organic compounds are a major source of indoor air pollution. Many of these chemicals can lead to serious health problems, especially with long-term exposure. Understanding the primary VOC contributors and their potential health effects can help individuals take steps to reduce exposure and protect their health. 

 

Next Steps to Reduce VOC Exposure  

One of the best ways to achieve lower VOC levels is by removing the sources. Storing gas cans, paint, and other substances outside of the home helps reduce indoor VOC concentrations. Additionally, removing plug-in air fresheners and scented items can lessen the amount of airborne chemicals. For cleaning and personal care products, keeping them in airtight containers further minimizes their release of VOCs into the air.

Improve ventilation by opening windows and doors often. If this is not possible, consider using a VOC-removing air purifier with a carbon filter. Though it’s impossible to eliminate all VOCs, these steps can help maintain lower levels and promote a healthier indoor environment. 

 

 

Concerned about the VOCs in your home or workspace? Home Air Check can help!   

 

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