A comprehensive investigation of toxicity and pollution potential of municipal solid waste landfill leachate

• Published in: The Science of the total environment 2022-09, Vol.838 (Pt 1), p.155891-155891, Article 155891
• Main Authors: Anand, N., Palani, Sankar Ganesh
• Format: Article
• Language: English
• Subjects: Analytical hierarchy process; Comet assay; Landfill leachate; Leachate pollution index; Physicochemical characterisation; Risk assessment; Seed germination study
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.155891

It is evident from the literature that research on the treatment of leachate generated from municipal solid waste (MSW) landfills has been a focus area of environmental management. However, the available information is discrete because most studies have reported only one or a couple of aspects of either closed or active MSW landfill leachate treatment. Hence, this investigation has focused on comprehensive attributes of both closed landfill leachate (CLL) and active landfill leachate (ALL), including generation, characterisation, and toxicity assessment to quantify and establish their pollution potential. The results indicated that CLL generation is higher (188.59 m3/d) than ALL (49.53 m3/d). The concentrations of principal physical, chemical, and biological constituents and concomitant leachate pollution index were higher in CLL (33.20) than in ALL (26.65). Furthermore, the germination indices of CLL (57.48) and ALL (79.14) and tail DNA damage of CLL (56.49%) and ALL (23.8%) ratified greater phytotoxicity and genotoxicity potential, respectively of CLL over ALL. The reasons for the variations in the generation, characteristics, and toxicity of CLL and ALL were discussed in detail. Evaluation of the commonly used landfill leachate treatment methods through the analytical hierarchy process confirmed that the activated sludge process and Fenton oxidation process are the most and least preferred treatment methods. The comprehensive investigation of CLL and ALL have established their pollution potential and the inevitable necessity for their treatment. The findings of this investigation will serve as a ready reference for researchers from academia and industry who work on the monitoring, treatment, and management of landfill leachate. [Display omitted] •Leachate generation was more in closed landfill than active landfill during the study.•Active and closed landfill leachates induced phytotoxicity and genotoxicity.•Closed landfill leachate had higher ecotoxicity and contamination potential.•Extreme risk quotient values of landfill leachates necessitate appropriate treatment.•Most efficient landfill leachate treatment was chosen by analytical hierarchy process.