Phytoremediation of indoor air pollutants: Harnessing the potential of plants beyond aesthetics

Indoor air pollution has emerged as a major threat to human health worldwide that needs to be dealt urgently. The present review is an effort to overview the different indoor air pollutants (CO2, volatile organic compounds (VOCs) like formaldehyde, benzene, nitrous oxide, trichloroethylene, fluorine, ammonia, radon, aldehyde, hydrocarbons etc.) their hazardous effects on human health, potential of indoor plants in their remediation and their practical utility. Besides providing oxygen to breathe, multifaceted roles of indoor plants have been well documented. Plants were used since decades for indoor decorations based on their aesthetic value, but now studies are focused on screening plant species for their efficiency in absorption of indoor air pollutants. The basis for phytoremediation is the potent efficiency of some plants to assimilate, degrade, or modify toxic pollutants into non-toxic ones. Phytoremediation seems to be the key solution to improve indoor air quality as it has many potential advantages (simple, potentially cheap, and easily implemented) in comparison to other traditional or latest methods. Breathing walls, portable air filters for rooms or whole house filtration through heating, ventilation and air conditioning systems are some of the technologies developed, to reduce indoor air pollution and improve indoor air quality but all these are costly, resource consuming and still there is question on their efficiency. Detailed account of morphological, anatomical and molecular mechanisms underlying plant leaves and leaf associated microbes in reduction of pollutants have been reviewed that could help in developing cost effective and eco friendly remediation technologies. This review gives a brief discussion about air phytoremediation to improve effectiveness of this technology in practical use.