An Innovative Bioremediation Approach for the Removal of Antibiotic and Antiretroviral Drug Contaminants From Wastewater Using Chlorella spp.

South Africa's widespread use of antiretroviral drugs and antibiotics generates significant pharmaceutical waste, overwhelming treatment plants and contaminating water. Therefore, improved wastewater treatment solutions are urgently needed. In this study, Chlorella spp. was investigated as a sustainable bioremediation agent for removing sulfamethoxazole, efavirenz and nevirapine from water. Results exhibited that extended light exposure enhanced photosynthetic activity and biomass accumulation. Furthermore, high algal concentrations accelerated growth, but excessively high densities led to overcrowding and nutrient depletion, while lower densities reduced cell‐to‐cell interactions and growth rates. Removal efficiencies ranged from 10% to 60% for efavirenz, 5% to 51% for nevirapine and 10% to 50% for sulfamethoxazole under controlled conditions (pH ~ 7, 23°C, 20:4 h light–dark cycle, 150 rpm orbital shaking, 10‐day incubation and initial pharmaceutical concentrations ranging from 0.25 to 5 mg/L). These rates were due to interactions between the pharmaceuticals and polar functional groups on the Chlorella spp. cell surface, enhancing adsorption. FTIR and SEM analyses confirmed these interactions, contributing to pollutant removal. The findings of this study highlight Chlorella spp. as a promising, low‐cost solution for mitigating pharmaceutical pollution, with strong potential for integration into existing wastewater treatment systems and scaling up for large‐scale municipal applications.