 VOCs are everywhere: at homes, at dry cleaning units, at food processors, at petroleum refineries, at airports and automobile service stations, at electronics and chemical plants, at print and paint shops etc. VOCs are those chemicals that exposed to air volatilize readily. So, these compounds contribute to air pollution by their vapour and to water and soil pollution by that fraction which can be carried deep into the soil by rainwater and melting snow. VOC and the environment: VOCs are dangerous for humans, fauna and flora. Firstly, these compounds have been proved to cause a variety of adverse health effects (Minnesota Department of Health, 2003, Regional Environmental Assessments, 2002; U.S. EPA, 2003). Generally, allergic skin reaction, dizziness, headaches, eye and respiratory tract irritation, coughing, visual disorders, memory impairment, confusion, anemia and fatigue are some of the symptoms associated with short-term exposure. Kidney, liver, brain damage, cardiac sensitization reactions and also damage to the nervous, reproductive and immune systems are caused by long-term exposure. VOCs are also “endocrine impostors”. Some are also known or suspected of causing cancer. Also, the natural plant processes can be destroyed or interrupted by some organic volatile compounds. In the atmosphere these chemicals are transformed in other compounds even more dangerous for humans, fauna and flora. The ground level or “bad” ozone, a key ingredient of urban smog, is created by a chemical reaction between oxides of nitrogen (NOx) and volatile organic compounds in the presence of sunlight. Repeated exposure to ozone pollution may cause a variety of health problems (Clean Air Counts, 2003); ozone also reduces the growth rate of trees and agricultural production. VOCs participate in the greenhouse effect, acid rains and stratospheric or “good” ozone depletion, which are serious environmental problems (Avila et al., 1998). Consequently, VOCs are a great group of air pollutants and our duty is to eliminate them from being released. For this reason, firstly, we must know who are they and which are their sources.
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