Using of Calendula officinalis L. Plant Extracts in Removing Some Heavy Metals from Polluted Water

In recent years, heavy metals have become major threats to human health. Over the past decades, many traditional methods have been used to remove these pollutants from water, including ultrafiltration, reverse osmosis, ion exchange, solvent extraction, and chemical precipitation. However, these methods have disadvantages such as high cost. In this study, aqueous and alcoholic extracts of Calendula officinalis L. were introduced to remove heavy metals from polluted river water as a new environmental sustainability. Five heavy metals (Fe, Ba, As, Mn, and Sr) were monitored, and their concentrations in river water were tested using inductively coupled plasma (ICP) spectrometry. The results showed that the alcoholic and aqueous extracts of Calendula officinalis L. were highly effective in removing 100% Fe, 96% Ba, 100% As and Mn, and 92% Sr. The best removal rates were recorded at pH 8, removal time 30min, and extract concentration of 0.3g/ L of contaminated water. C. officinalis extract has been shown to be effective in removing heavy elements and is considered a promising future alternative in the field of water treatment.