What are VOCs?

Volatile organic compounds (VOCs) are a large family of pollutants made up of hundreds of gases we find in the air. These gases can be naturally occurring or caused by human activity and contribute to poor air quality, particularly indoors. 

To be extra-precise, when we use the term VOCs we are specifically referring to non-methane volatile organic compounds. There are two common elements that unite all these different gases in the VOC family. They’re all:

  • Organic compounds: they have at least one carbon atom and one or more other element (hydrogen, halogen, oxygen, sulfur, phosphorus ...)
  • Volatile, their boiling point is low (they evaporate easily).

Among the most common VOCs are butane, ethanol, acetone, benzene or formaldehyde. 

Where do VOCs come from?

There are many sources of VOCs. Some of these are naturally occurring, while others are related to human activities.

The main VOC emitting sectors are:

  • Residential (using cleaning products and solvents at home)
  • Manufacturing industry (also largely due to the use of solvents)
  • Production of hydrocarbons (oil refinery for example)
  • Transportation (car exhaust and fuel)

It should be noted that vegetation is a major source of natural VOCs, for example, the synthesis of aromatic compounds responsible for the fragrance of flowers or plants.

VOCs are often considered to be indoor pollutants because the highest concentrations are generally found in confined areas. The main sources of VOCs indoors are:

  • Furniture: construction materials like plastic, glues, varnishes, paints, and fabrics.
  • Maintenance products: disinfectants, deodorants, insecticides, and cleaning products.
  • Cosmetics: nail polishes, perfumes, and hair products.

paint bucketsA fresh paint can emit high quantities of VOC

What are the health impacts of VOC exposure?

Exposure to VOCs can cause problems —from headaches, respiratory tract irritation, and nausea, to more serious conditions such as breathing difficulties, dermatological problems, or reproductive disorders. For example, some VOCs, such as formaldehyde, found in glues and some wood resins, benzene (in car exhaust), or perchlorethylene (used for dry cleaning), are classified as carcinogenic to humans.

These compounds, which are frequently found in the air in homes or workplaces, are notably associated with what is called "sick building syndrome", which describes a set of syndromes (fatigue, irritations, headaches…) linked to poor air quality in buildings.

Frequent ventilation and using a limited number of cleaning products (preferably of natural origin) are good ways to control your exposure to VOCs at home.