Effects of the Leached Plastic Additive (Bisphenol-A) on Chlorella vulgaris and Wastewater Bioremediation

Bisphenol A (BPA) is a common plastic additive found in wastewater (WW) due to its extensive use in industrial and consumer products. As a known endocrine disruptor, BPA poses serious ecological and human health risks, yet its removal remains inefficient in conventional WW treatment plants. This novel study investigates the impact of high environmental BPA concentrations (5 mg/L and 25 mg/L) on Chlorella vulgaris in a WW-mimicking environment, assessing microalgal growth, metabolic activity, nutrient removal, and BPA degradation. Exposure to BPA led to a significant reduction in esterase activity and an increase in intracellular reactive oxygen species (ROS) levels, indicating cellular oxidative stress and metabolic disruption. Despite these effects, C. vulgaris maintained stable photosynthetic pigment levels, demonstrating a resilient photosynthetic function. The bioremediation potential of C. vulgaris was also compromised, with nitrogen and phosphorus removal efficiencies decreasing by up to 38% and 34% in the presence of 5 and 25 mg BPA/L, respectively. Nevertheless, the microalga exhibited the ability to degrade BPA, with removal efficiencies of 34% for 5 mg/L and 21% for 25 mg/L after 168 h, while abiotic degradation was minimal. These findings confirm the potential of C. vulgaris as a promising sustainable approach for BPA bioremediation but also highlight critical challenges at high contaminant concentrations.