Unpacking the Heavy Metal Menace in Tunisia's Phosphogypsum

Tunisia grapples with a significant challenge: managing tons of phosphogypsum, a byproduct of phosphate mining that's causing serious environmental harm. This study delves into the heavy metal contamination in phosphogypsum waste from the Mdhilla region, Gafsa, in southern Tunisia. Researchers analyzed six samples from storage heaps near a chemical plant, focusing on zinc (Zn), chromium (Cr), copper (Cu), nickel (Ni), and cadmium (Cd). These metals were measured using atomic absorption spectrometry. Various indices like the geo-accumulation index (Igeo), contamination factor (FC), degree of contamination (DC), and sediment pollution index (IPS) were calculated to gauge pollution levels. The metals' abundance in the region follows this order: Zn > Ni > Cr > Cd > Cu. The contamination indices reveal significant pollution, primarily due to cadmium, nickel, and copper.