With an increasing number of paint manufacturers lining the shelves with ‘low-VOC’ or ‘no-VOC’ products, we’re now well aware that it’s wise to avoid volatile organic compounds (VOCs).

They’re commonly found in paints, but also in carpeting, furniture, adhesives, cleaning products, and a range of other building and interior materials. If a product has a strong smell, there’s a good chance it contains VOCs.

So why should we avoid VOCs, and just how dangerous are they, anyway?

The VOCs in building and interior products are compounds that evaporate readily into the surrounding environment as a product of off-gassing. As paint dries, for example, it releases VOCs into the air as the solvent evaporates and leaves behind the dried pigment and other components.

VOCs have been linked to a wide range of adverse health effects ranging from the mild – such as respiratory irritation – to the more serious, such as cancer. They’re one of the main culprits behind Sick Building Syndrome, where occupants of a building complain of headaches, fatigue and other symptoms that disappear after leaving the building. Poor indoor air quality has been linked to decreased productivity for employees, and impacts academic performance for school students.

VOCs can fall into two main groups: natural VOCs emitted by plants, decomposing organic matter, and even our own exhalation of carbon dioxide; and man-made or ‘anthropogenic’ VOCs, which are manufactured. While compounds from each category can be relatively harmless or toxic depending on the chemical makeup, synthetic VOCs and their applications typically cause more of a concern.

The health issues caused by VOCs in indoor environments depend on the amount of VOCs present in the air, the length of time they are present, and how frequently people are exposed to them. Symptoms may be very different if a person is exposed to a high level of a particular compound for a brief period of time, compared to someone who is cumulatively exposed to smaller doses for longer. Those more sensitive to chemicals, such as asthmatics, will obviously be affected more strongly under most circumstances.

It’s important to realise that not all VOCs are created equal – some have far more serious health effects than others. Take benzene, for example. As well as being found in sources such as tobacco smoke and stored fuels, it’s used in some paints, adhesives, and furniture wax. Benzene is a known human carcinogen, particularly after long-term exposure, and can cause a range of other nasty health effects including harm to bone marrow, a decrease in red blood cells and a less effective immune system.

Another VOC to watch out for is formaldehyde, which is found in a variety of sources including paints, adhesives, floor finishes and some wood products. Formaldehyde is released slowly and will cause irritation of the eyes and any mucous membranes, particularly in humid environments, which may speed up its rate of release. The effects of temporary exposure to formaldehyde are reversible, but since formaldehyde is another known carcinogen, it’s definitely a compound to avoid.

Not all VOCs are necessarily carcinogenic. Acetone is a solvent used to thin resins and clean tools, and can be found in some paints and varnishes. Despite its strong smell, it’s not considered particularly toxic and is not classed as a carcinogen. It will, however, cause irritation to the eyes upon contact and can trigger respiratory irritation in some cases.

Despite the clear evidence of the hazards of VOCs, they are still legal and widely used in many products. The best way to minimise or avoid them is to look for products marked ‘low-VOC’ or, even better, ‘no-VOC.’ Many paints are marketed with such labels, so avoiding VOCs here may seem easy compared to other interior products such as furniture. Knowing that a manufacturer’s claims regarding VOCs are genuine is another matter. Evidence of third-party certification, such as the Good Environmental Choice Australia (GECA) ecolabel, shows that a product has been assessed and that any VOCs (if present) are limited to safe levels.