"VOC" stands for Volatile Organic Compound. An organic compound doesn't mean it's green; in chemistry 'organic' means that it is carbon-based, which usually means fossil fuels (i.e. petroleum and coal). Volatile means that this compound is somewhat unstable in its state - meaning over time liquids convert to gases, some more quickly than others. A good example of this is aromatherapy, where volatile essential oils such as peppermint and rosemary are used. A volatile oil when exposed to air quickly gives off a scent.
This volatile quality is highly desirable in aromatherapy, not so much with paint, and for two reasons. First, some individuals are highly sensitive to scents and fragrances, and the mere odor of paint fumes - regardless of any health issues - are annoying, irritating, and in some cases produces a serious reaction such as an asthma attack. The second reason is that some organic compounds can be hazardous to health, and their volatility means that they are more easily absorbed into the body when they are in the air. An inert organic compound which doesn't give off fumes - left in place - usually isn't hazardous. Good examples of this are lead and asbestos. If lead and asbestos are undisturbed, there is little or no health risk. It's only when they are ingested (lead) or breathed in (asbestos) that they cause problems. Some paint components fall in this category. Hence the development of Low VOC paints.
Paint can give off VOCs while being applied, as it is drying and over time. Another thing to keep in mind is that lack of odor is no guarantee of lack of a VOC as some chemicals are odorless, even though they are producing irritating or even toxic gases. That's why utilities put an odor-causing substance in natural gas, because of itself it has very little detectable odor. Finally, even though a paint can's label may indicate its VOC content falls within the voluntary guidelines for a Low VOC product, if you have that paint tinted at the store, you're adding additional VOCs in the pigment which changes the overall VOC content of the paint.
If VOCs in paint are a concern to you, ask us about using a Low or Zero VOC paint on your next interior painting project. We also do our best to minimize odor by maximizing ventilation during application, and choosing paints which provide the best coverage with the least amount of paint. Both of these techniques help to minimize the amount of VOCs which end up in your home, and in your lungs.