Abstract
Biosolids, the solid byproducts of wastewater treatment, are widely applied to soils to enhance nutrient levels and organic matter. However, their use raises environmental and human health concerns due to the presence of anthropogenic organic contaminants. As such, there is a need to develop treatment strategies that can help remove these compounds before biosolids are land applied. This study investigates the potential of two white-rot fungal species to remove nine psychoactive pharmaceuticals from biosolids. Each species degraded eight compounds, achieving removal efficiencies between 48 and 99% after 60 days. Pleurotus ostreatus nearly completely (>90%) degraded desvenlafaxine, trazodone, and citalopram, while Trametes versicolor achieved over 75% degradation of desvenlafaxine, trazodone, and lamotrigine. Liquid culture (without biosolids) and biosolid experiments tentatively identified 41 fungal transformation products (27 for P. ostreatus and 36 for T. versicolor), of which many were formed from cleavage, hydroxylation, or demethylation reactions. These findings demonstrate that white-rot fungi can effectively grow on biosolids and degrade sorbed psychoactive pharmaceuticals. Overall, the results highlight mycoaugmentation as a promising and sustainable approach for mitigating pharmaceutical contamination in biosolids prior to land application.