Phytoextraction, phytotransformation and rhizodegradation of ibuprofen associated with Typha angustifolia in a horizontal subsurface flow constructed wetland

Abstract

a b s t r a c tWidespread occurrence of trace pharmaceutical residues in aquatic environments is of great concerns due to the potential chronic toxicity of certain pharmaceuticals including ibuprofen on aquatic organisms even at environmental levels. In this study, the phytoextraction, phytotransformation and rhizodegradation of ibuprofen associated with Typha angustifolia were investigated in a horizontal subsurface flow constructed wetland system. The experimental wetland system consisted of a planted bed with Typha angustifolia and an unplanted bed (control) to treat ibuprofen-loaded wastewater (~107.2 mg L À1 ).Over a period of 342 days, ibuprofen was accumulated in leaf sheath and lamina tissues at a mean concentration of 160.7 ng g À1 , indicating the occurrence of the phytoextraction of ibuprofen. Root-uptake ibuprofen was partially transformed to ibuprofen carboxylic acid, 2-hydroxy ibuprofen and 1-hydroxy ibuprofen which were found to be 1374.9, 235.6 and 301.5 ng g À1 in the sheath, respectively, while they were 1051.1, 693.6 and 178.7 ng g À1 in the lamina. The findings from pyrosequencing analysis of the rhizosphere bacteria suggest that the Dechloromonas sp., the Clostridium sp. (e.g. Clostridium saccharobutylicum), the order Sphingobacteriales, and the Cytophaga sp. in the order Cytophagales were most probably responsible for the rhizodegradation of ibuprofen.

Role of Design and Operational Factors in the Removal of Pharmaceuticals by Constructed Wetlands

“…Matamoros et al [20,64]; Hijosa-Valsero et al [15,65]; Ávila et al [23,35,38,59,61]; Matamoros and Salvadó [14]; Li et al [8]; Zhu and Chen [66]; Chen et al [17]; Vymazal et al [19]; Březinova et al [67]; Zhang et al [34]; Nivala et al [43] Biodegradation (aerobic) Sorption Dordio et al [44]; Dordio and Carvalho [28] Adsorption Auvinen et al [31] Photodegradation Reyes-Contreras et al [48]; Zhang et al [10] Plant uptake Hijosa-Valsero et al [15]; Li et al [51] Ketoprofen Biodegradation Hijosa-Valsero et al [15]; Zhang et al [27]; Chen et al [17]; Francini et al [62]; Zhang et al [34] Photodegradation…”

“…For instance, root uptake of ibuprofen was partially transformed to carboxyibuprofen, 2-hydroxyibuprofen, and 1-hydroxyibuprofen in the sheath (1375, 236, and 302 ng•g −1 , respectively) and in the lamina (1051, 694, and 179 ng•g −1 , respectively). The accumulation of transformation products (TPs) of ibuprofen in the leaves of Typha angustifolia is evidence of the phytotransformation of ibuprofen in plant tissues [51]. In addition to that, He et al [52] noted the phytotransformation of TPs of ibuprofen.…”

Removal of pharmaceutically active compounds in constructed wetlands: mechanisms and application

“…In the aqueous phase in the light compartment of CW2, occurrence of hydroxy-IBP was also observed resulting from photodegradation. Dihydroxy-IBP and carboxy-IBP were found in biodegradation studies of IBP [124,226], but were not observed in our studies reported here.…”

“…All seven tested PhACs were found to accumulate in both RR and SL tissues (Table 8.1). To date, there are studies in which plant uptake of CAF, NAP, IBP, DFC, and CBZ in wetland plant species was detected [104,158,226,396,398,399]; our data showing β-blocker uptake (i.e. MET and PRO) has not been reported previously.…”

“…Removal of all the PhACs tested was significantly lower in CW4 with the absence of plants [104]. Second, rhizodegradation of PhACs can be promoted with plants [158,226]. Plant roots can release oxygen and diverse exudates such as ions, inorganic and organic acids, proteins, and enzymes.…”