Phytoremediation of municipal solid waste leachate using Canna indica (L.) plants: A sustainable approach

The present study investigated the efficacy of Canna indica (L.) in the phytoremediation of municipal solid waste leachate over a 60-day period, focusing on various physicochemical parameters and bioaccumulation, enrichment, and translocation factors of heavy metals. The study indicated significant reductions in potential of hydrogen (pH), total dissolved solids (TDS), electrical conductivity (EC), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and various nutrients (phosphorus, calcium, magnesium, potassium, and sodium) across different leachate concentrations (0%-100%). The highest removal of BOD and COD occurred at 25% leachate, indicating C. indica's potential for organic pollutant remediation. Heavy metals like cadmium (Cd), chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), and lead (Pb) were notably reduced, especially at higher concentrations, demonstrating C. indica's effectiveness in detoxifying leachate. The bioaccumulation factor (BF) for heavy metals was greater than 1 at 50% and 75% leachate concentrations, indicating that C. indica effectively accumulated these metals. Enrichment factor (EF < 2 for Cr, Cu, Pb, Zn, and Mn; EF > 2 for Cd) suggested moderate enrichment of most metals, with Cd showing the highest enrichment. The translocation factor (TF) was less than 1, indicating low mobility of metals from roots to leaves. Overall, C. indica demonstrated strong potential for the phytoremediation of municipal waste leachate, particularly at 25% concentrations, and can be considered as an effective hyperaccumulator for various heavy metals. Therefore, C. indica presents a promising and cost-effective method for improving the quality of heavily contaminated leachate.