Analyzing the Efficacy of Salvinia Molesta and Pistia Stratiotes as Phytoremediation Agent for Heavy Metals

Abstract

To rejuvenate our declining ecosystems, it is imperative to promptly face the issue of heavy metal contamination, which serves as the underlying cause for pollution globally. Phytoremediation, which is the ability of certain plants to accumulate, break down, or neutralize pollutants in water, soil, or air, offers a promising solution. The current investigation aimed to assess the efficacy of Salvinia molesta and Pistia stratiotes in removing heavy metals from apparel industrial wastewater. In a controlled indoor environment, the wastewater underwent treatment using these plants, while control tanks of the same size without any plants were maintained for comparison. This setup included three replicates for each treatment. Over 18 days, samples of the wastewater were collected and analyzed for the presence of Cadmium (Cd), Copper (Cu), and Zinc (Zn) using an Atomic Absorption Spectrophotometer (AAS) every three days. An initial analysis of the untreated wastewater was conducted. Statistical analysis employed one-way ANOVA to compare the average concentrations in the effluent and the removal percentages across various treatment conditions. Pistia stratiotes exhibited a higher Cd reduction rate (29.97%) compared to Salvinia molesta (18.13%). Tanks containing Salvinia molesta showed a more substantial Cu removal rate (52.47%), while Pistia stratiotes demonstrated a lower Cu reduction (42.37%). As for Zinc (Zn), it decreased by 22.89% and 17.87% in tanks where Salvinia molesta and Pistia stratiotes were used, respectively. This study, conducted over an 18-day trial period, underscores the effectiveness of both plant types in removing Cd, Cu, and Zn from the wastewater. The preferential absorption was observed for Cu over the other two metals. For Salvinia molesta, the removal efficiency followed the sequence: Cu>Zn>Cd, whereas for Pistia stratiotes, it was Cu>Cd>Zn. These findings demonstrate that both plant species can thrive while accumulating these heavy metals in apparel industrial wastewater.