The endocrine-disrupting chemical, bisphenol A (BPA) has attracted much attention due to its estrogenic
activity and widespread environmental distribution. The toxicity and cellular stresses of BPA to
Chlamydomonas mexicana and Chlorella vulgaris and its biodegradation/bioaccumulation by both
microalgae were investigated. The 120-h EC50 of BPA for C. mexicana and C. vulgaris were 44.8 and
39.8 mg L1, respectively. The dry cell weight and chlorophyll a content of both microalgae decreased
with increasing BPA concentration higher than 10 mg L1. Growth of C. vulgaris was significantly inhibited
at 50 mg L1 BPA compared to C. mexicana. Total nitrogen (TN) and total phosphorous (TP) removal was
higher in C. mexicana than in C. vulgaris. Microalgae performed the bioaccumulation and biodegradation
of BPA to varying extents at different initial BPA concentrations. The highest rates of BPA biodegradation,
24 and 23% by C. mexicana and C. vulgaris, respectively, were achieved at 1 mg L1 BPA. Both the total fatty acid and carbohydrate contents increased with increasing BPA concentration. This study demonstrated
that C. mexicana was more tolerant to BPA and could be used for treatment of BPA contaminated aqueous
systems.