title: Variation of the phytotoxicity of municipal solid waste incinerator bottom ash on wheat (Triticum aestivum L.) seed germination with leaching conditions.
abstract: Municipal solid waste incinerator bottom ash (MSWIBA) has long been regarded as an alternative building material in the construction industry. However, the pollutants contained in the bottom ash could potentially leach out and contaminate the local environment, which presents an obstacle to the reuse of the materials. To evaluate the environmental feasibility of using MSWIBA as a recycled material in construction, the leaching derived ecotoxicity was assessed. The leaching behavior of MSWIBA under various conditions, including the extractant type, leaching time, liquid-to-solid (L/S) ratio, and leachate pH were investigated, and the phytotoxicity of these leachates on wheat (Triticum aestivum L.) seed germination was determined. Moreover, the correlation between the germination index and the concentrations of various chemical constituents in the MSWIBA leachates was assessed using multivariate statistics with principal component analysis and Pearson's correlation analysis. It was found that, heavy metal concentrations in the leachate were pH and L/S ratio dependent, but were less affected by leaching time. Heavy metals were the main pollutants present in wheat seeds. Heavy metals (especially Ba, Cr, Cu and Pb) had a substantial inhibitory effect on wheat seed germination and root elongation. To safely use MSWIBA in construction, the potential risk and ecotoxicity of leached materials must be addressed.
authors.affiliation: State Key Laboratory of Pollution Control & Resource Reuse, Tongji University, Shanghai 200092, PR China.
authors.forename: Khamphe
authors.initials: K
authors.lastname: Phoungthong
authors.affiliation: State Key Laboratory of Pollution Control & Resource Reuse, Tongji University, Shanghai 200092, PR China. Electronic address: zhanghua_tj@tongji.edu.cn.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China; Centre for the Technology Research and Training on Household Waste in Small Towns & Rural Area, Ministry of Housing and Urban-Rural Development of PR China (MOHURD), Shanghai 200092, PR China.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Shao
authors.affiliation: Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China; Centre for the Technology Research and Training on Household Waste in Small Towns & Rural Area, Ministry of Housing and Urban-Rural Development of PR China (MOHURD), Shanghai 200092, PR China.
authors.forename: Pin-Jing
authors.initials: PJ
authors.lastname: He
mesh_terms: D060729:Coal Ash / Q000633:toxicity*; D003252:Construction Materials; D018525:Germination / Q000187:drug effects*; D017745:Incineration / Q000379:methods*; D019216:Metals, Heavy / Q000633:toxicity; D015999:Multivariate Analysis; D012639:Seeds / Q000187:drug effects* / Q000254:growth & development; D062611:Solid Waste / Q000032:analysis; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D060729:Coal Ash; D019216:Metals, Heavy; D062611:Solid Waste; D014874:Water Pollutants, Chemical
keywords: Bottom ash; Heavy metal leaching; Multivariate analysis; Phytotoxicity; Wheat seed germination