US EPA

5094790 

Journal Article 

Does plant species selection in functional active green walls influence VOC phytoremediation efficiency? 

Irga, PJ; Pettit, T; Irga, RF; Paull, NJ; Douglas, ANJ; Torpy, FR 

2019 

Yes 

Environmental Science and Pollution Research
ISSN: 0944-1344
EISSN: 1614-7499 

26 

13 

12851-12858 

English 

30891698 

10.1007/s11356-019-04719-9 

WOS:000465460000020 

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85063193194&doi=10.1007%2fs11356-019-04719-9&partnerID=40&md5=b2a8802d8df558d8c00f98828d80525b
Exit
 

Volatile organic compounds (VOCs) are of public concern due to their adverse health effects. Botanical air filtration is a promising technology for reducing indoor air contaminants, but the underlying mechanisms are not fully understood. This study assessed active botanical biofilters for their single-pass removal efficiency (SPRE) for benzene, ethyl acetate and ambient total volatile organic compounds (TVOCs), at concentrations of in situ relevance. Biofilters containing four plant species (Chlorophytum orchidastrum, Nematanthus glabra, Nephrolepis cordifolia 'duffii' and Schefflera arboricola) were compared to discern whether plant selection influenced VOC SPRE. Amongst all tested plant species, benzene SPREs were between 45.54 and 59.50%, with N. glabra the most efficient. The botanical biofilters removed 32.36-91.19% of ethyl acetate, with C. orchidastrum and S. arboricola recording significantly higher ethyl acetate SPREs than N. glabra and N. cordifolia. These findings thus indicate that plant type influences botanical biofilter VOC removal. It is proposed that ethyl acetate SPREs were dependent on hydrophilic adsorbent sites, with increasing root surface area, root diameter and root mass all associated with increasing ethyl acetate SPRE. The high benzene SPRE of N. glabra is likely due to the high wax content in its leaf cuticles. The SPREs for the relatively low levels of ambient TVOCs were consistent amongst plant species, providing no evidence to suggest that in situ TVOC removal is influenced by plant choice. Nonetheless, as inter-species differences do exist for some VOCs, botanical biofilters using a mixture of plants is proposed.