This is a little blurb on VOCs – what are VOCs and why do they matter?
VOCs (volatile organic compounds) are molecules containing carbon that easily evaporate under typical indoor/outdoor conditions. The list of chemicals that fall under this definition is vast. In fact, many VOCs occur naturally in the environment because they are made by plants – they’re supposed to be there! However, it’s the man-made VOCs that have become synonymous with the bad-VOCs.
How toxic each one is depends on which one it is and its dose, frequency, and duration of exposure. When it comes to negative impact on the earth and human health, they generally fall into 3 categories: Outdoor VOCs that harm the ozone layer, Indoor VOCs that harm humans directly, and Neutral VOCs that do no harm that we know of. The federal government (Environmental Protection Agency) regulates outdoor VOCs to an extent (you may remember the buzz about chlorofluorocarbons or CFCs many years ago!). However, indoor VOCs are not regulated federally, in part due to insufficient data to really know how bad indoor VOCs are for a person’s health at typical indoor concentrations. There are many sates, however, that do regulate certain indoor VOC concentrations (California in particular).
Examples of harmful VOCs include propane, butane, acetone, ethanol, isopropyl alcohol (this is rubbing alcohol!), pesticides, fire retardants. Other VOCs are known carcinogens, such as benzene, formaldehyde, perchloroethylene, and methylene chloride. They are in many common household products including paint, paint strippers, aerosol sprays, cleaners, disinfectants, air fresheners, fuels, automotive products, hobby supplies, and dry-cleaned clothing. They may cause mucosal irritation, asthma exacerbations, headache, nausea, vomiting, and dizziness particularly with acute exposure, like stripping paint in an unventilated room. By the way, whenever a product states “work in well-ventilated area” it’s because that product contains harmful VOCs.
While renovating or building new construction, most people consider the effects of VOCs on indoor air quality. Examples of typical building materials that contain VOCs are new carpeting, floor tile, primer/paint, caulk, adhesives, wood stain/sealers. That “new house smell” is primarily due to VOCs!! Once these materials are used, they continue to release VOCs into the air over time, hence the term “off-gassing.” In fact, the highest concentrations of indoor VOCs are typically found in new construction homes.
When it comes to evaluating products labelled as “zero VOC” or “low VOC”, there are a few things to keep in mind. First, what compounds are they classifying as VOCs — this is where companies can fudge the data and here’s why: the Environmental Protection Agency (EPA) has a list of VOCs it regulates but only for the purpose of protecting the ozone layer. If a VOC does not harm the ozone, it is “exempt” from this list, even though it may be harmful to humans. So, a company will say zero or low VOC, using the government’s list of VOCs, but they neglect to mention that their product contains exempt VOCs that are known carcinogens like methylene chloride. Secondly, what is the concentration of VOCs in the product. Some may call 200g/L low but others have stricter standards and call < 50g/L low.
As I mentioned earlier, there are no federally regulated standards for indoor VOC concentrations. However, Americans are pushing to create standards of their own. Similar to the Energy-Star label or the Water-sense label, there are Eco-labels that independently verify a product’s claim that it is low VOC. The Greenguard label is a big one for building materials. Look for this label on low VOC products, and you can at least be confident that the product’s claims were evaluated independently to earn that seal.
As I was researching this topic for this blog, I learned something new about my own behavior that increases the amount of VOCs leached into my home: my cleaners. I actually do not buy “green” cleaners because, well, I love the way other products clean. What I learned is that most cleaners have high VOC content and unless stored in air-tight containers, some amount of this gas will continually evaporate into the environment. Similar situation for other stored products e.g. left-over paint…
The paint I used in The Project was Sherwin-Williams Harmony paint, which is a low-VOC, Greenguard labelled product. There are many other low VOC paint brands out there (in fact consumer reports took a look at them and rated them. What they found was large difference in the amount of VOC in each “low-VOC” product. http://www.consumerreports.org/cro/magazine-archive/march-2009/home-garden/interior-paints/overview/interior-paints-ov.htm
Take Home Points:
- Volatile Organic Compounds (VOCs) is a very broad category of carbon-containing molecules that easily evaporate under typical indoor/outdoor conditions.
- Many VOCs are harmful (hence the hype), but recognize there are many VOCS that do no harm.
- Certain VOCs destroy the ozone layer, are carcinogenic, or cause nausea, headache, vomiting, light-headedness, rash, asthma exacerbations.
- Improving indoor air quality by using low-VOC building products is one way to have positive impact on overall health and the environment.
- When evaluating a product labeled as “Zero-VOC” or “Low-VOC”, look for a GreenGuard or other independent party eco-label that verifies that claim.
- There a variety of ways to measure VOCs in a product and variable definitions of zero/low-VOC so also realize there is no industry standard.