Improved rhizoremediation for decabromodiphenyl ether (BDE-209) in E-waste contaminated soils

Abstract

An experiment was conducted to improve rhizoremediation for decabromodiphenyl ether (BDE-209) contaminated soil from typical E-waste dismantling areas. Plants of ryegrass (Lolium perenne L.) and rice (Oryza sativa L.) were cultivated in aged-contaminated (initial concentration of 346.3 µg BDE-209$kg-1) and freshly-spiked (initial concentration of 3127 µg BDE-209$kg-1) soils, coupling with the agricultural modification strategies of compost addition and/or arbuscular mycorrhizal fungi (AMF) infection, respectively. 60 days' growth of ryegrass significantly facilitated the dissipation of BDE-209, with the most effective in its rhizosphere in treatment inoculated with AMF; the BDE-209 dissipation rates achieved 51.9% and 22.8% in rhizosphere, and 43.5% and 19.8% in non-rhizosphere, for aged-contaminated and freshlyspiked soils, respectively. 120 days' growth of rice with simultaneous inoculation of AMF and addition of compost was the most effective in facilitating BDE-209 dissipation in agedcontaminated soil, with the removal rates of 53.3% and 48.1% in rhizosphere and nonrhizosphere soils respectively; while for freshly-spiked soils, the most effective removal was achieved by compost addition only, with the BDE-209 dissipation rates of 27.9% and 26.6% in rhizosphere and non-rhizosphere soils, respectively. High throughput sequencing analysis of rhizosphere soil DNA showed that responses in microbial communities and their structure differed with plant species, soil pollution dose, AMF inoculation and/or compost addition. Actinomycetales, Xanthomonadales, Burkholderiales, Sphingomonadales, Clostridiales, Cytophagales, Gemmatimonadales and Saprospirales were the sensitive responders and even possibly potential functional microbial groups during the facilitated removal of BDE-209 in soils. This study illustrates an effective rhizoremediation pattern for removal of BDE-209 in pollution soils, through successive cultivation of rice and followed by ryegrass, with rice growth coupled with AMF inoculation and compost addition, while ryegrass growth coupled with AMF inoculation only.

Plant uptake, translocation and metabolism of PBDEs in plants of food and feed industry: A review

“…Compared to reference plants without fungi an increased depletion of 4750 ng g -1 DM to 2250 ng g -1 DM of BDE-209 was observed. Similar results were presented by Feng et al (2019).…”

Plant Uptake, Translocation and Metabolism of PBDEs in Plants

“…Its secondary effect of enhanced microbial biodegradation and detoxification of PBDEs in the mycorrhizal area was shown several times in literature. As an example, increased depletion of 470 ng g DM −1 towards 2250 ng g DM −1 was observed for BDE-209 comparing rice plants with and without mycorrhizal fungi [57].…”

Deciphering Historical Water-Quality Changes Recorded in Sediments Using eDNA

“…Dehalococcoides, which is a genus of bacteria within the class Dehalococcoidia, can dehalogenate halogenated organic compounds in a mode of anaerobic respiration (Loffler et al, 2013) and are tolerant to many pollutants (such as benzenes, PCBs and recalcitrant pollutants) (MaymoGatell et al, 1997;Maphosa et al, 2012;Mayer-Blackwell et al, 2017). The taxa Gemmatimonadales and Sva0485, which also showed a significant positive correlation with the concentration of Br and Cl, were reported to be possibly active in the degradation of bromated or chlorinated PAHs such as PBDEs, TBBA and linuron (Dealtry et al, 2016;Feng et al, 2019;Jiang et al, 2020). Burkholderiales and Xanthomonadales, which showed a significant positive correlation with the concentration of TOC, were reported to have a strong degradation effect on organic matters, especially for PAHs or PBDEs (Nunez et al, 2012;Crampon et al, 2018;Feng et al, 2019).…”

“…The taxa Gemmatimonadales and Sva0485, which also showed a significant positive correlation with the concentration of Br and Cl, were reported to be possibly active in the degradation of bromated or chlorinated PAHs such as PBDEs, TBBA and linuron (Dealtry et al, 2016;Feng et al, 2019;Jiang et al, 2020). Burkholderiales and Xanthomonadales, which showed a significant positive correlation with the concentration of TOC, were reported to have a strong degradation effect on organic matters, especially for PAHs or PBDEs (Nunez et al, 2012;Crampon et al, 2018;Feng et al, 2019). Our results further indicated that Dehalococcoidia, Gemmatimonadales and Sva0485 would potentially be candidate microbial signals for persistent bromide pollutants in the sediment, and Burkholderiales, Xanthomonadales, Gemmatimonadales and Sva0485 would potentially be candidate microbial signals for persistent PAH pollutants in the sediment.…”

“…This was consistent with studies arguing that Xanthomonadales can exist extensively in sediments with wood substrates and plant residues, which may indicate less anthropogenic disturbance (Schmalenberger et al, 2013;Herve et al, 2014). However, many studies have claimed that Xanthomonadales can be simulated in PAH-or PBDEpolluted environments and can improve the degradation of these pollutants (Nunez et al, 2012;Crampon et al, 2018;Feng et al, 2019). There was no clear statement about Gemmatimonadales's potential to reveal a polluted environment in Sun et al's paper (Sun et al, 2013).…”