Introduction: Hospitals generate substantial volumes of highly contaminated wastewater, posing serious environmental and public health concerns. Hospital wastewater (HWW) contains pharmaceutical residues, heavy metals, disinfectants, pathogens, and antibiotic-resistant bacteria, many of which are not completely removed by conventional wastewater treatment plants (WWTPs).
Methods: This study evaluated the performance of hospital WWTPs in Tehran, Iran. A total of 128 effluent samples were collected in 2024 from 59 hospital WWTPs affiliated with Iran University of Medical Sciences. Samples were analyzed to assess treatment efficiency using key physicochemical and microbiological parameters, including biochemical oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids (TSS), total coliforms, and fecal coliforms, according to standard methods.
Results: All hospitals operated wastewater treatment systems; however, 8.33% consistently failed to comply with national effluent discharge standards. Regarding disposal routes, 66.6% of effluents were discharged into municipal sewer systems, 21.6% into infiltration wells, and 11.6% were reused for irrigation.
Conclusion: Despite the presence of treatment systems, deficiencies in pollutant removal and improper discharge practices remain concerns. Ensuring full connection of hospital WWTPs to municipal sewer networks would enable further treatment at centralized facilities, reducing environmental and health risks. Strengthened regulatory enforcement and adoption of advanced treatment technologies are essential to improve hospital wastewater management and safeguard public health.