Recent occurrence of pharmaceuticals in freshwater, emerging treatment technologies, and future considerations: A...

Pharmaceuticals represent an emerging class of pollutants raising significant environmental health concerns, with their presence in freshwater systems linked to adverse aquatic ecosystem impacts and acceleration of antibiotic resistance development. This narrative review examines recent (2019-2024) pharmaceutical occurrences in freshwater globally, analyzes contamination pathways, evaluates compound-specific degradability, and assesses treatment technologies. Analysis revealed significant pharmaceutical contamination in freshwater sources across the six major continents, primarily entering through wastewater treatment plant effluents, groundwater recharge processes, and inadequate sanitation infrastructure/septic systems. Stark geographical disparities were observed, with regions lacking centralized treatment infrastructure showing multiple-fold higher concentrations, particularly in Africa and Latin America (exemplified by amoxicillin levels reaching 272,156 ng/L in Lagos, Nigeria). Pharmaceutical profiles reflected local healthcare patterns, with antimalarials and antiretrovirals prevalent in endemic regions. Globally prevalent compounds included caffeine, acetaminophen, ibuprofen, carbamazepine, sulfamethoxazole, amoxicillin, and diclofenac. While some compounds like caffeine showed relatively good removal in conventional treatment systems, their high usage rates overwhelmed treatment capacity. Others, particularly carbamazepine, demonstrated high recalcitrance to conventional treatment methods. Advanced oxidation processes and membrane technologies showed high removal efficiencies, while biochar-based systems emerged as promising, cost-effective alternatives using locally available resources. The findings underscore the need for both centralized and decentralized treatment approaches. Point-of-use technologies emerge as crucial immediate interventions for regions with inadequate infrastructure, while advanced technologies show promise for large-scale applications. The review emphasizes that municipalities should conduct systematic screening to identify locally prevalent pharmaceuticals, as treatment requirements vary significantly with local usage patterns, making a one-size-fits-all approach ineffective.