Reducing plant uptake of a brominated contaminant (2,2′,4,4′‑tetrabrominated diphenyl ether) by incorporation of maize straw into horticultural soil Leilei Xiang a,b , Hongjie Sheng a , Min Xu a,b , Marc Redmile-Gordon c , Yongrong Bian a , Xinglun Yang a , Xin Jiang a , Fang Wang a,b, ⁎ a Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China b University of Chinese Academy of Sciences, Beijing 100049, China c Department of Environmental Horticulture, Royal Horticultural Society, Wisley, UK HIGHLIGHTS • Maize straw incorporation decreased BDE-47 bioaccumulation in carrot. • Maize straw incorporation reduced the bioavailability of BDE-47 in soil. • Maize straw incorporation enhanced the dissipation of BDE-47 in soil. • Soil bacterial community was mainly af- fected by available P, TOC, and bioavail- able concentration of BDE-47. GRAPHICAL ABSTRACT abstract article info Article history: Received 30 November 2018 Received in revised form 20 January 2019 Accepted 22 January 2019 Available online 24 January 2019 Editor: Jay Gan Application of crop residues is a conventional practice that contributes to crop production through nutrient returns and other benefits to soil health: driving soil physicochemical and biological functions. However, little is known about the impacts of straw residue incorporation on the bioavailability of organic pollutants and associated changes in microbial community structure in contaminated soils. In this study, maize straw was added to a soil contaminated with a model polybrominated diphenyl ether (BDE-47). A pot experiment was conducted and planted with carrot (Daucus carota L.). We found that straw addition greatly reduced the bioavailability of BDE-47, changed the bacterial community structure and affected a range of soil physiochemical properties. Moreover, the amount of BDE-47 that had accumulated in carrot roots and aboveground tissues was significantly reduced. This study may therefore de- scribe an effective agronomic strategy to reduce the bioavailability of polybrominated diphenyl ethers (PBDEs) in a soil used to grow high value vegetable crops. This strategy draws on traditional wisdom and shows promise as a practical method to support horticultural production systems, remediate soils, and help to ensure food safety. © 2019 Elsevier B.V. All rights reserved. Keywords: Straw PBDEs Bioavailability Uptake Reduction Microbial community 1. Introduction Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) widely used in a range of commercial products, Science of the Total Environment 663 (2019) 29–37 ⁎ Corresponding author at: 71 East Beijing Road, Nanjing 210008, China. E-mail address: wangfang@issas.ac.cn (F. Wang). https://doi.org/10.1016/j.scitotenv.2019.01.297 0048-9697/© 2019 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv