Fungi, bacteria, and microalgae help break down stubborn pollutants like pesticides, pharmaceuticals, and heavy metals in soil and water. Fungi stood out for their ability to decompose complex compounds, such as polychlorinated biphenyls (PCBs) and petroleum hydrocarbons, thanks to enzymes like laccase and peroxidases. White rot fungi were especially effective, and their biofilms proved valuable in wastewater filtration systems.