Analysis of Heavy Metal Contamination in Macroalgae from Surface Waters in Djelfa, Algeria

International audience; The heavy metals concentration in algae can be used as a bioindicator of the pollution of an ecosystem. In the present study, we determined the levels of the elements Fe, Pb, Cu, and Zn in chlorophyta of the species Cladophora, Spirogyra, Chara, and Zygnema. The samples were collected in February of 2021 in three different locations in Algeria (Dar El Chioukh lake, Oued Mellah, and Oued Boucedira). Our results showed that all four algae species accumulated high levels of heavy metals in surface water, with concentrations ranging from 3.14 to 5600 mg/kg. The Pb levels in all four species exceeded the recommended standard set by the International Atomic Energy Agency (IAEA) of 0.574 mg/kg, with the highest concentration of 50.85 mg/kg recorded in Cladophora at the first location. Similarly, Fe and Cu levels were found to be above the recommended standard, with maximum concentrations of 5600 mg/kg and 82.5 mg/kg, respectively. On the other hand, Zn levels were found to be lower than the standard of 128 mg/kg, with the highest concentration of 47.5 mg/kg recorded in Spirogyra at the third location. The results of the principal component analysis (PCA) confirmed that the heavy metal pollution of these waters was of anthropogenic origin, likely stemming from urban, industrial, and agricultural activities.