Volatile organic compounds are considered as one of the most common air pollutants. The Environmental Protection Agency of the United States has divided the volatile organic compounds into three different classes. they are very volatile organic compounds or (VVOCs). volatile organic compounds (VOCs). and semi volatile organic compounds (SVOCs) (USEPA). There are various sources for VOCs, they can either have an organic /natural origin, or they can be produced artificially. Over the last thirty odd years VOCs have become a major concern for environmentalists all around the globe. In the recent years several studies have been conducted by the scientists for controlling the detrimental effects caused by VOCs.
Naturally occurring volatile organic compounds are mainly isoprenoids and oxygenated substances. They are usually released by plants and animals (Di Carlo, Brune and Martinez). However, plants are reported to produce greater level of VOCs as compared to the animals (Atkinson and Arey). The occurrence of biogenic VOCs can prove detrimental for the troposphere, as these gaseous compounds can react in the presence of nitrogen oxide to produce tropospheric ozone that may lead to greenhouse effect (Holopainen and Gershenzon). VOCs are generally produced by plants in stressful environment, this leads to impairing of carbon fixation that results in accumulation of greenhouse gases like methane in plants and the atmosphere (Atkinson). The artificially occurring VOCs are have diversified sources. Sometimes artificial volatile organic compounds are directly used, and sometimes they are produced as a byproduct during some domestic or industrial operations. VOCs are abundantly used in household commodities like paints. air fresheners. refrigerators. insect repellents.