Every product we use may have some impact on the environment. The air that we breathe, the water we drink and the food we eat all contain naturally occurring chemicals. For example, the smell of the forest is due to a mixture of certain organic chemicals. Many of these chemicals are classified as volatile organic compounds or VOCs. These chemicals are not harmful in their own right, but if they mix with nitrogen oxides (NOx) under the right conditions (presence of sunlight and warm temperatures) they can react to produce ground-level ozone that can have harmful effects on human health.
Man-made chemicals, including solvents, are used in everyday items, such as paint, cosmetics or cleaners, that allow us to protect, beautify and clean. With certain important exceptions, the solvents used in products such as coatings, inks, and consumer products are generally classified as VOCs. In many cases, emissions of these chemicals are controlled (through incineration or recycling, or are captured, using control technology). Alternatively, they may be emitted into the air after they perform their function in an industrial application or in product use.
Most organic solvents rapidly biodegrade in the soil or wastewater, (i.e., they do not bioaccumulate or persist in the environment), and have relatively low ecotoxicity. Air emissions from these organic solvents degrade readily in the atmosphere and when that occurs in the presence of NOx and sunlight ground level ozone can be produced. This is a key component of the summertime smog contributing to poor air quality, which can have a harmful effect on human health and plant life. The rapid degradation of organic solvents in the lower atmosphere also means that these VOCs do not cause any problems with the stratospheric ozone layer because they degrade before they get to the stratosphere. There are some chemicals that don’t degrade in the lower atmosphere, but do react in the stratosphere and thereby contribute to the formation of so-called "ozone holes."
Solvent emissions from VOC-containing products represent a relatively minor portion of total VOC emissions. Other sources include emissions from automotive tailpipes, manufacturing, combustion, and power industries, and also natural emissions from trees and vegetation. VOCs from many man-made sources, including many solvent uses, already are subject to regulations or will be over the next few years. In implementing VOC regulations, it is important to focus on emissions that have an environmental impact—that is, emissions that contribute to ozone formation in areas where ozone levels are a concern. It does not make economic sense to regulate VOC emissions in areas where ozone levels do not exceed federal standards, or where reductions in man-made VOC emissions will have no environmental impact (either because biogenic VOCs are dominant, or the area is NOx-limited, meaning that only reductions in NOx levels will have an impact). For further information on regulations affecting solvents, please visit the regulatory information section of this site.
Solvents and Air Quality
Chemical Waste Disposal
Biodegradability and Organic Compounds
