Environmental discharge of pharmacologically active compounds (PhACs): Elucidating the known, unknowns, and effective management strategies

• Synergistic effects of pharmaceutical cocktails pose added risk to aquatic health • Precautionary measures can mitigate the impact of chemicals on aquatic ecosystems • More in-situ studies that closely mirror environmental realities are needed. • A model to reduce pharmaceutical levels in aquatic ecosystems is proposed Pharmacologically active compounds (PhACs) are designed to help diagnose, treat, or prevent ailments and diseases; however, the majority of PhACs are not completely metabolizable by target organisms. Consequently, they are released into the aquatic environment from manufacturers as well as users, and without discharge guidelines and regulations, end up in the environment. While there are limited studies to support their direct impacts on human health at current environmental concentrations, there is an emerging concern stemming from studies on model aquatic organisms inciting negative ecological responses. Despite these avalanches of scientific evidence, there are regulatory and management gaps in removing or reducing the amount and rate at which pharmaceutical compounds enter natural water sources. This review identifies key knowledge and regulatory gaps associated with the presence of PhACs in the aquatic environment and proposes a management model for effective control at the source, consumption, and wastewater treatment levels. By synthesizing current evidence and highlighting the limitations of existing regulatory approaches, this paper underscores the need for more proactive and integrated management strategies capable of addressing both known and emerging challenges.