Variation of the phytotoxicity of municipal solid waste incinerator bottom ash on wheat (Triticum aestivum L.) seed germination with leaching conditions. (March 2016)

• Record Type: Journal Article
• Authors: Phoungthong, Khamphe; Zhang, Hua; Shao, Li-Ming; He, Pin-Jing
• Is Part Of: Chemosphere. Volume 146(2016)
• Page Start: 547
• Page End: 554
• Publication Date: 2016-03
• Subjects: Bottom ash -- Heavy metal leaching -- Phytotoxicity -- Wheat seed germination -- Multivariate analysis; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2015.12.063
• Languages: English
• ISSNs: 0045-6535

Abstract

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. Highlights: The leaching behaviors and phytotoxicity characterization of MSWIBA were studied. Wheat seed germination bioassay was used to evaluate the MSWIBA leachates. Ba, Cr, Cu and Pb were linked to wheat germination and root elongation inhibition. Recommendations were developed for safer reuse of MSWIBA in construction.