Phytoremediation of benzene, toluene, ethylbenzene and xylene contaminated air by D. deremensis and O. microdasys plants

Background: People usually spent about 90% of their time indoors, which are probably more polluted than outside the buildings. High levels of volatile organic compounds (VOCs) are known as causes of sick building syndrome. The present study was designed to determine the quantitative effects of some plants to improve the quality of the environmental air. Results: D. deremensis and O. microdasys were chosen for the present study. There is no report of using O. microdasys for cleaning the air from pollutants. So, in this study, the effectiveness of O. microdasys in air removing from pollutants was studied and compared with D. dermensis. O. microdasys plant can remove 2 ppm concentration benzene, toluene, xylene and ethylbenzene from air in test chambers completely after 48, 55, 47 and 57 hours, respectively. The removal rates of benzene, toluene, xylene and ethylbenzene (BTEX) from air in the test chambers were 1.18, 0.54, 1.64 and 1.35 mg/m(2)d(1), respectively. Conclusions: If an office containing 2.5 ppm of each of BTEX and had an approximate volume of 30 m(3), it contains 16, 8, 22 and 22 mg/m(3) benzene, toluene, xylene and ethylbenzene, respectively. Using ten O. microdasys pots with the same size used in this study, can remove benzene, toluene, xylene and ethylbenzene totally after 36, 40, 30 and 39 hours. The authors recommended studying the efficiency of the plants for removal of BTEX from air at higher range of concentrations such as 20-30 ppm.